Westlake Publishing Forums

Hi,
my new milling machine is down to the suction shoe fully operational ... only I`m myself currently not quite mobile.
What can I do when this machine is not so easy to reach by foot?

Not really a problem, there are still many things that I would like to build as a model in scale 1: 22.5.

The research for this ran and always runs besides, so that I could gather some pictures and measurements to a rail- and a street-bound model.

In my youth the cobblestone street in front of our house were torn open and and sewer were installed. I can remember I often watched as a young boy, as the cable dredger dropped his shovel onto the ground, then the crunch when closing and lifting ..... unfortunately I have no paper images, only the memory.  When the road was closed again with the paving stones, there was a loud metallic rumble ... a street roller leveled the surface.

Of course at this time my dearest wish was to get such a roller...
at Christmas I got the SIKU-roller (https://www.google.de/search?biw=1142&bih=1114&tbm=isch&sa=1&ei=k5nHWo3rCseykwWo47iwCg&q=siku+walze+kemna&oq=siku+walze+kemna&gs_l=psy-ab.3...13499.16007.0.16303.6.6.0.0.0.0.88.408.6.6.0....0...1c.1.64.psy-ab..0.1.88...0i30k1j0i8i30k1.0.c--I6zsgNR4).

In recent days I started with two new projects on the computer.

Now to the first new venture:
It is a KEMNA-stree roller Gigant 8 (or 10 - both have the same dimensions).
Over the years I had collected some pictures and information that I have looked at more closely now. In various forums there were now and then a few pictures and descriptions of the Hatra / Kemna-rollers, for example at bauforum24 (https://www.bauforum24.biz/forums/topic/986-kemna-walzen/)
Images you can find for example here: click (https://www.google.de/search?biw=1142&bih=1114&tbm=isch&sa=1&ei=IJvHWqnQCMOYsAfGlL2ACA&q=hatra+walze+kemna+Gigant+&oq=hatra+walze+kemna+Gigant+&gs_l=psy-ab.3...494146.496385.0.497286.8.8.0.0.0.0.104.486.7j1.8.0....0...1c.1.64.psy-ab..0.0.0....0.2WXJNxe6PY4)

Some info at  Hatra (https://www.hatra-baumaschinen.de/stra%C3%9Fenwalzen/dreiradwalzen/)
Here (https://www.hatra-baumaschinen.de/historie/)  about the history of the company. From 1949 the company produced at Lübeck Kemna-rollers in license and did further development for the three-wheeled street rollers.

On this page there is also a roughly dimensioned sketch of the Giant 8-roller. This, however, has different height and aspect ratios.
I scaleded this sketch in Photoshop to 1:22.5.
Agreed the length, the height was too great - agreed the height, the length was too short.
There are another black and white sketch in the head of Hatra page - top right. A screenshot of this image has been scaled to length ... and lo and behold, the result was better than before.   :)

Kemna_Walze_Grundriss_000 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_000.jpg&hash=9dae90ed8591241bff34bc7121a865d8b985bbea)
found at:https://www.hatra-baumaschinen.de/

This page plan was mounted together with a scaled front view in 90 °  in the CAD program.
The lines roughly traced and dimensioned according to the following table:

Kemna_Walze_Abmessungen (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Abmessungen.png&hash=6b1b60e65f9fb83caac5503ff7921d90a26dd7f8)

Two days ago it looked like this:

Kemna_Animation_001 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Animation_001.gif&hash=40f3b5e29d558dd63ce4780ec5b98974f749a45d)


Now it gives more pictures:

Kemna_Walze_Grundriss_009 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_009.jpg&hash=c62ba04e0378973b2d8ab4bec429b057cc64182d)


Kemna_Walze_Grundriss_012 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_012.jpg&hash=c97ba73b4cd2deb45eb346f844490e358654f2b1)


Kemna_Walze_Grundriss_013 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_013.jpg&hash=c1341d2381926db57322a6dd979dabece8fc6fb6)


Kemna_Walze_Grundriss_014 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_014.jpg&hash=dc8687531a0cd6dee5239da1de78a07cd978601b)

The space for drive elements inside are: width = 29,0mm  -  length = about 133,0mm and height = some 55,0mm.


Kemna_Walze_Grundriss_015 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_015.jpg&hash=3cb14c1e748270497fefe55754d6c29d4d66f3fb)


Frithjof

Please post updates as you build the model! -- Russ

Yes, please! I'm looking forward to seeing more!

@Russ and Greg
But gladly!

Since I know only the coarse outer dimensions of the roller, but also want to position the details in the right place, I have taken images from the Web to help.

The following video clip on YouTube shows the roller from all sides, as well as to get a good sound impression:

https://youtu.be/SonE63gse1k

I created several screenshots and equalizes and scales them to parallel.

www_youtube_com:watch_v_SonE63gse1k (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903www_youtube_com%3Awatch_v_SonE63gse1k.jpg&hash=0e7d8406d492e42bb28670dfdece510b7fff821a)
equalized and scaled excerpt from video clip: https://www.youtube.com/watch?v=SonE63gse1k

With Photoshop, the image was scaled to a known height and width. Through the help lines, I could then determine the proportions and transferred to the Cad program.

This is how the drawing looked today:

Kemna_Walze_Grundriss_016 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_016.jpg&hash=5d24edd40dc5dca2d2a1dd9f177d0a1387af25fc)


Kemna_Walze_Grundriss_018 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_018.jpg&hash=c98e91c9e2554132a74472946e05e85e4ff499f8)


Kemna_Walze_Grundriss_019 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_019.jpg&hash=e79a0e788783101768e050523000154942571c2c)

Kemna_Walze_Grundriss_021 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_021.jpg&hash=68a9223736a55f35c8b1ddaff385e1d11f8c0e9f)


Kemna_Walze_Grundriss_022 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_022.jpg&hash=ecddd82be1515f0bc05f6084f205f613115075b0)

It was just a little bit drawn in the last few days.


Kemna_Walze_Grundriss_028 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_028.jpg&hash=c808782aa0b9b1c1c708ffd8645dd49a5598ed1a)


First, a stl file of the retaining bar of the front roller has been prepared for 3D printing:


Kemna_Walze_Grundriss_024 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_024.jpg&hash=cf1c73d468c77ee4fb15832be05df337e6f38e5b)


Thanks to a nice contact, soon I will be able to obtain more detailed documentation from the Hatra / Kemna Gigant 8 roller.
That pleases me a lot, because then I can not only scale the positions of the many small hexagon screws in addition to the exact external dimensions.
Before the data goes to the router, I can adjust the dimensions and get an even more coherent model.

Kemna_Walze_Grundriss_035 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_035.jpg&hash=7ec9a8ca1f00168b2171467cfa3bfae53cec81bd)

I'm not just counting the rivets


The roller had 3 gears at the following speeds:

Kemna_Walze_Grundriss_036 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_036.jpg&hash=e8018e4be2f02cbf4e8a9f3a3c69e03bfc528def)


The current drive is an existing high-cut 2225 Faulhaber geared motor.

Kemna_Walze_Grundriss_034 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_034.jpg&hash=bd485c3fa2e6797ac635bbc011ed2ab3e3400995)

It can be operated with up to 24 volts - at about 12 volts at idle he has around 30 rpm and decent power ... under load, he might drive the roller well prototypical.


Kemna_Walze_Grundriss_029 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_029.jpg&hash=1941c2035b53203541eb1eb7ae7a2b6a3b22e483)

However, the space for a 12 volt battery is then a bit tight. Let's see if it works with a StepUp controller then to drive with a 3.7Volt Lipo cell .....

Kemna_Walze_Grundriss_030 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_030.jpg&hash=c257cddc33f5dd1d09272b89710326846721966e)


Kemna_Walze_Grundriss_032 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_032.jpg&hash=d2427ea40013191ffa00ed111ec49888bbb91aef)


Kemna_Walze_Grundriss_033 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_033.jpg&hash=ce2e08130ee98868988c80836a5e71b34e74d885)


I had an interesting discussion in the last few days with some friends regarding the rear axle drive:

a) Drive with a motor on the rigidly connected rear roller wheels (the simplest solution)
b) Drive with a differential or planetary gear to prevent the roller will moving straight ahead when cornering (for a differential is down too little space)
c) As above, but with one motor per rear wheel to reduce the speed of the inner wheel, or to increase the outer wheel when cornering over a corresponding controller (the most expensive solution)
d) split rear axle with only one driven rear wheel. The front steering wheel must be built accordingly heavy. (I would like that most - at about 20cm top speed / min right and left cornering probably should not turn out so differently fast)

Would be glad if you still have tips, or can tell from your experience.

Oh, that will be a beauty! And those Faulhaber motors are superb. -- Russ

Wow I didn't realize you were planning to motorize this! Very cool.

Hi Frithjof,

Nice futur project! As always, perfect technical study!

Franck

Franck, nice to see you again. What have you been doing? -- Russ

Thanks for your comments!

It continues with many pictures!

The roller will receive a differential, I found it at AFV (http://afv-model.com/343/%22FleXaxle%22-System-FleXaxle-Differenzial-Stahl-Set). They have a " FleXaxle Differential Steel Set" which can be a good compromise with the dimensions, if I cut the bottom of the roller below the input bevel gear.
The diameter of the input bevel gear is 28mm, the differential case has 19.0mm - at a width of 22,0mm (just fits!)


I have already installed it virtual:

Kemna_Walze_Grundriss_037 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_037.jpg&hash=7b13b85467271437530a861dc6b289c9fa6e219c)


Kemna_Walze_Grundriss_040 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_040.jpg&hash=8f15ae3d59d64bd0755de24a51e9bef0f3dd5b06)


The lower cover sheet will be tuned in the width to the input.

Kemna_Walze_Grundriss_041 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_041.jpg&hash=5787f8e97ae0b626669aa4bd20d0428c5bcc0696)


Kemna_Walze_Grundriss_043 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_043.jpg&hash=6020dd061fdf3b4ee10ca7fb017b3ea2fd2f127b)




In order to be able to better service all RC components and the motor with drive axle, everything will be pre-assembled on a subframe and inserted from below into the roller.

Kemna_Walze_Grundriss_056 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_056.jpg&hash=68f19a2cc507a33a983d45d50eea6fb34c80d359)


Kemna_Walze_Grundriss_054 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_054.jpg&hash=1a0bed994a042508b29b2c5a69a6e172ea18fec8)


The suspension is not yet drawn!


Kemna_Walze_Grundriss_044 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_044.jpg&hash=86ae9674800bce466275eb35371c4cf9a69fecdf)


Kemna_Walze_Grundriss_057 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_057.gif&hash=1b94508e184c52140b8c24881e4e5a8f1f8e3c31)


Kemna_Walze_Grundriss_062 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze_Grundriss_062.jpg&hash=c6399806bbb19cd044b99843885496045c86deb8)


Kemna_Walze-Gigant_8_066 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_066.jpg&hash=eda7af2eda395bd8accf8c5001e427f07ae3ccf8)


Here the differential from AFV:

Kemna_Walze-Gigant_8_076 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_076.jpg&hash=4873bd5878f1b398d05fec74ca12576f473282bf)



With the drawings I'm done except for a few small details, such as the hinge of the middle hood cover ... I would like to do it quite flexible.

You can see an animation it  shows the assembly of the subframe into the roller.:

Kemna_Walze-Gigant_8_067 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_067.jpg&hash=e347499580f16e00ace8013f3ec23d8a85b2b7e5)


Kemna_Walze-Gigant_8_072 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_072.gif&hash=d5cf8b0c98b6361b3c4eca80e68cb4949a3b6e3b)


In addition to the differential, further parts for the roller construction have arrived recently.

I had sent a STL file of the front roller retainer to two 3D printer companies.
Within 10 days I got the part printed by Shapeways in Brass Raw.


Kemna_Walze-Gigant_8_073 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_073.jpg&hash=e2533b687869acdedf604318e6fb2a36f2b3132d)


Above, as it was delivered. The outer surfaces were already been polished by Shapeways ...
and below after sandblasting, the visible steps were no longer a problem.

Kemna_Walze-Gigant_8_074 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_074.jpg&hash=e9dc97ba7540498311eb7d5c1c65d0405ec53937)


Earlier printed results from this provider had some strong stairs on the curves, so I asked Kalle Stümpfl to print the file on his printer in plastic parallel. I saw some very clean printed surfaces from this provider before.

Also this part has arrived shortly.

Kemna_Walze-Gigant_8_075 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903P10701Kemna_Walze-Gigant_8_075.jpg&hash=a4863e15a53a47cde709ef8929210dd5cc6f14f3)


Apart from the fact that I hold a plastic part in my hand, there is no reason to complain about it.
But I will continue to stay with brass, the experiment with the Dutch provider made me very positive. I think, I'll print a smaller part soon ...


Also more brass raw material came and wants to become as a model.

Kemna_Walze-Gigant_8_077 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_077.jpg&hash=bb46e2bb162fbe64a7442e39770cdc73805ba8a8)


The first plates for the inner frame and the bearing blocks for the rear axle you can see as follow. 


Kemna_Walze-Gigant_8_081 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_081.jpg&hash=f653919fb84d412b927d5500469af5a2ea48c5a7)


Kemna_Walze-Gigant_8_082 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_082.jpg&hash=5581934b685efc04616ebfbf9d29bf95f9c8c2d4)

I just love watching the way you work and develop yours ideas and drawings in beautifully crafted parts ...... I really do wish I had just a little of your skills and talent

Makes the way I constructed my "roller" amateurish in the extreme

http://www.finescalerr.com/smf/index.php?topic=2352.0

Gordon, your statement is completely incorrect. Go stand in the corner.

Frithjof, your engineering and execution impresses me beyond words. Question: Does Kalle Stümpfl (or anyone else) print parts of higher resolution and/or quality than Shapeways? Is the material durable?

Russ

@Gordon
I have to agree with Russ, your models are unrivaled, they are built so well. It does not matter if you build in plastic or brass - it counts the result ... and I will never reach your aging effects ;-)

@Russ
Kalle Stümpfl (Impressum (http://www.ks-modelleisenbahnen.de/html/impressum.html)) used the Formlab 2-printer  (https://www.google.com/search?q=Formlab+2&client=safari&rls=en&source=lnms&tbm=shop&sa=X&ved=0ahUKEwjprtnT5efaAhXTxaYKHUwECm8Q_AUICigB&biw=1196&bih=1093)
He has a lot of experience, so he mixes different printer fluids for example. He can adjust the pressure parts as customers want. A thin railing of a scale 1:45 locomotive is so flexible that it still has not broken off after a year, although many customers have touched and bent this part at several exhibitions. Kalle treats the printed parts in such a way that they will be able to stand in the sun without being painted.

The roller retainer from Shapeways was build by lost wax methode. You can choose different materials. I took brass raw (44,00€ incl tax). The outer surfaces were still polished.
The quality of the plastic material is good enough for a stand model. However my roller will drive with RC control, so brass is more welcome as material for me.
Both surfaces are comparable. The plastic part of Kalle cost 33,00 € incl. Tax.



More and more parts are coming from the milling machine.

Kemna_Walze-Gigant_8_085 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_085.jpg&hash=1100838dc479434fbae26830cdc2229aa3d23810)


The pendulum frame has a model height of 5.6mm and a thickness of 1.3mm.

To customize it, I had two options:
a)Milling an unrolling of the file. For this purpose, a corresponding part of a 1.5 mm thick Ms58 sheet would have been planned off by 0.2 mm in order to obtain a 1.3 mm material thickness - then drill holes and mill out the outer contour. After that I would have bent the frame over a template and soldered together at the interface.

I opted for b) .
Use found a 90mm x 60mm x 6.0mm MS58 rest plate.
First, a 3.0mm deep pocket with the dimensions of the brass plate was milled into an MDF board and the part inserted. After that the 8 holes to hold the milling piece came into the material. It is not possible to clamp the plate in a small vise, because only a gossamer edge remains at the end.
Now a 0.4mm deep pocket was milled into the brass over the frame area to then mill the outside and inside contours.


Kemna-Pendelrahmen_Fraesdatei_01 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna-Pendelrahmen_Fraesdatei_01.jpg&hash=6de072bdede452636a27b609289ac88a86b0aeef)


For further processing, I left several thin holding webs inside..


Kemna-Pendelrahmen_Fraesdatei_02 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna-Pendelrahmen_Fraesdatei_02.jpg&hash=ca37a72db2c7bde7786993f640cd826bd1e43756)


For the exact positioning of the 0.6mm, 0.8mm and 2.0mm holes in the frame I have milled two templates of 10.0mm Pertinax.

Kemna_Pendelrahmen_Bohrschablonen_01 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Pendelrahmen_Bohrschablonen_01.gif&hash=628ef39c7f618383d7cc2c929ba460ee3e645c6c)



Kemna_Pendelrahmen_Bohrschablonen_02 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Pendelrahmen_Bohrschablonen_02.jpg&hash=29949071b755a22432684b31ce97727bccd5c5b2)


Kemna_Pendelrahmen_Bohrschablonen_03 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Pendelrahmen_Bohrschablonen_03.jpg&hash=03e86b89dc074929d64dc3f8f2d5e1225313034d)



Now the remaining holding webs were separated with a 0.3mm saw blade and the interfaces were smoothed with a sandpaper file.


Kemna_Walze-Gigant_8_086 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_086.jpg&hash=e15b71299a3911e7f98f703f156eba1c476633f9)


In the interior space of the scooter must be placed beside the engine a receiver, a servo for the front axle and a control shaft to the handwheel in the cab .... if then a battery should give enough power, it may not have only 200mA.
Oh, sound with speakers, lighting and then a driver - there is not much room left. Let's see what comes out in the end.


Kemna_Walze-Gigant_8_087 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_087.jpg&hash=8e24f74d0f5fe1b3d7da8cf514e1b6eaa9bcfe56)


Kemna_Walze-Gigant_8_088 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_088.jpg&hash=e83ff4483f66006164ca76b1a443739d5984eb23)


Kemna_Walze-Gigant_8_089 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_089.jpg&hash=c6f0107ac3248ebeaa21c55a1865ff79f0752fe8)


Kemna_Walze-Gigant_8_092 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_092.jpg&hash=0c81cfa053a0447c58d1690c99f96269d13da281)

Brilliant design! I like the way the mechanical parts will fit into the model.

After all parts are milled for the inner frame, it continues with the outer skin. It is completely made as a unrolling of 1.0mm MS58.


Kemna_Walze-Gigant_8_094 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_094.jpg&hash=9ba374b408ec3b869d4d7f02f50159c46df78137)


All holes, recesses and depressions are taken into account.

Kemna_Walze-Gigant_8_093 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_093.jpg&hash=b9871905b8362baceeb5b8252d6ca14f3a4ffae3)


The front tip will be annealed and bent over a template later.

Kemna_Walze-Gigant_8_095 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_095.jpg&hash=f99c6d81919a11e8ec8a0472f4da5375b8986a0e)



The lower part of the front filler was milled, which will take up the rotation axis of of the front roller.
Since it has a height of 13.61mm, but my longest small cutter only has a cutting length of 12.0mm, I shared the part.
From a 10,0mm MS58 material, the lower part was built.
The upper brass part came out from a piece of 4.0mm MS58 rod. Then the five center holes were drilled and the outer contour milled. In the holes 1.0mm brass pins for precise positioning will be mounted for soldering.
Subsequently, the brazed parts are milled to the height of 13.61mm.

Kemna_Walze-Gigant_8_096 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_096.gif&hash=a7ee05016b978c57ac385e24e4c0d1034d0e9c93)


Kemna_Walze-Gigant_8_097 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_097.jpg&hash=9d8f5ca688a0a8abc359e18c31e130fd6e4b0075)


Kemna_Walze-Gigant_8_098 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_098.jpg&hash=d00d1b2c82c556e16a658fa677528c489c6f488e)
Lower section with 3.0mm sintered bronze bushing.

Kemna_Walze-Gigant_8_099 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_099.jpg&hash=4f163105dea584444bb7b6b470a44e0045adc62d)


Kemna_Walze-Gigant_8_100 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_100.jpg&hash=9c48ffca9df16f7f5737da83d4e6ba57674e9d19)


Kemna_Walze-Gigant_8_101 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_101.jpg&hash=e4434af9a321a4ad362309b7ac72883de71b445d)


The unrolling of the outer skin I milled shortely.

Kemna_Walze-Gigant_8_102 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_102.jpg&hash=f8d1116b9d149c2a56eae4c3d76743c0e666b3a2)


After the sheet was machined from the inner side (0.5mm indentations on the lower edges and the two sides of the cab), I milled a pocket of 1.0mm depth into a MDF board so that I could machine the milled brass sheet from the outside. It was fixed with Tesakrepp and then I milled 0.2mm deep pockets. Later I can position the lamp holder and the round nameplate "Klöckner" exactly.

Kemna_Walze-Gigant_8_103 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_103.jpg&hash=a17a8de9ae0f33ddf6514aaeaf82f3fc0a190f02)


To bend the settlement, I've milled two bending templates made of 20mm thick MDF.

Kemna_Walze-Gigant_8_104 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_104.jpg&hash=d1bc964e442b532f4cdc145fc77c7409eace27be)


In the first template, I chose the radius of the previously milled brass block and bent the sheet annealed in the middle with the help of a hard wooden stick. The second side was not parallel to the angle, so I could bent the outer skin more slightly.

Kemna_Walze-Gigant_8_110 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_110.jpg&hash=75a81e402a47eda0ebb7888e6f21a7a325f2028e)


Kemna_Walze-Gigant_8_105 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_105.jpg&hash=b11c970a22ba8ec56b115ae4e0e0c74f3261952a)


As can be seen in the following picture, the curve of the sheet does not yet lie exactly on the curve of the template.

Kemna_Walze-Gigant_8_106 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_106.jpg&hash=53b3c3293432ca759ac165b4bf935678fe22143d)


Kemna_Walze-Gigant_8_107 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_107.jpg&hash=8ba6233561c18f9de6b6b747c63e179197bd7f11)


So a new stencil was milled without further ado, now with a smaller radius and a slightly stronger angle of the second side.


Kemna_Walze-Gigant_8_108 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_108.jpg&hash=19147090d5bcc17b0a8c3be304ccba6adbad6368)

It fits better now!


Here's a first non-virtual impression of what the roller will look like. The parts are put together only loosely - the brass block hangs something wrong in the rounding.


Kemna_Walze-Gigant_8_109 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_109.jpg&hash=cfa4db5b85d1b4b78fd4af2d1fc9d49420c126bb)



As a last point today a look at the router:
It's great to be able to put several things in parallel.


P1-Montage_125 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9350%2F2903P1-Montage_125.jpg&hash=4068698224fca7b077f298359d2a252425315299)


P1-Montage_126 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9350%2F2903P1-Montage_126.jpg&hash=3bda839cc4c8c92f173660ff9d768779a197bb70)

It's does just get better and better ...... that front roller frame is really wonderful

Thank you for the kind words but remember the paint and final finish was down to the great talents of John Tolcher

Is anybody else as impressed as I am? This is just insanely outstanding!

And thank you for the information about Kalle Stümpfl.

Russ

Gordon, Russ,  thanks so much for your reception!

Today there are only a little progress to report.

The roof was milled from 0.3mm nickel silver sheet and bent in several passes with a roll bender until the radius matched the angle of the both profiles milled from 1.5mm brass (MS58) sheet.
Again it was used a victim sheet (similar to here (http://www.buntbahn.de/fotos/showphoto.php?photo=72345&size=big&password=&sort=7&thecat=7443) ever shown) to get no kinks at both ends.
The wall thickness of these milled profiles is 0.25mm.


Kemna_Walze-Gigant_8_111 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_111.jpg&hash=1125c8403d2cf9e11536ed9b56bd64108b6d93e6)

Subsequently, the two sides were bent at previously milled 0.15 mm deep grooves. Both ends were around 10.0mm longer. Later I cutted them with my  sheet metal cutting machine  (http://www.buntbahn.de/fotos/showphoto.php?photo=41381&size=big&password=&sort=7&thecat=7443) (by placing of 1.4mm distance plates) to the final dimension. Just as here (http://www.buntbahn.de/fotos/showphoto.php?photo=44404&size=big&password=&sort=7&thecat=7443) shown.

To bend a purchased 1.5mm x 1.5mm brass profile and drill four 0.6mm holes into it would have been too costly for me. Of course the M0.6 x 4.0mm screws will be shortened so that it does not overhang under the roof.

Gasp ! gone a bit dizzy ! you are a true master with your works of art
Gordon do not dispare you are doing all-right hang in there !
Barney

Oh, yes, quite impressed! And the router -- I want one of those!

Wow!!!!!! Just incredible!!!!! Allan

And don't forget all the CAD design and engineering necessary before Frithjof could produce those parts. Does anyone else around here feel like a beginner by comparison? -- Russ

I'm greatly impressed!

This type of work is far, far beyond me, but I find it incredibly fascinating to follow along.

Thanks to all for the nice comments!

Since I am currently waiting for a few castings for the road roller, the Demag ML15 has priority.

A little bit further I could come with the wheels by now.

Kemna_Walze-Gigant_8_123 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_123.jpg&hash=d6953ef5225ccfbd1a75f2716bc24bc0d7f03332)

Each brass rod section I had each ordered 10.0mm longer than needed. The parts were clamped on the lathe and processed.

Kemna_Walze-Gigant_8_124 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_124.jpg&hash=fbb67a4d3fc1b25f723d7d18c68f731bdd02935a)

The wheels will be a bit lighter soon.


The back panel still needs a small handwheel.

Kemna_Walze-Gigant_8_121 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_121.jpg&hash=60ab5627f8ec2255cc601edc4781de9fb43a8cb8)

Kemna_Walze-Gigant_8_122 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_122.jpg&hash=4cc6a147c86f82f78e91d6aa01e78048ce481912)



Drawn the handwheel looks huge, but it has a diameter of only 7.0mm!

Kemna_Walze-Gigant_8_119 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_119.jpg&hash=814f6ffc8d5077302b2293033d7440dce8060a24)


After several back and forth, finally I got the small handwheel printed in plastic - not in brass.

Kemna_Walze-Gigant_8_125 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_125.jpg&hash=47d487e25fc5d5266722ba4feb063a7fb7ec61dc)

Each part looks perfect. -- Russ

Today we continued with the first roller wheel.
After the protruding approach was turned off, it goes ahead on the milling machine.
The material was removed on both sides so that it looks like the green wheel in the drawing at the end.

Kemna_Walze-Gigant_8_129 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_129.jpg&hash=a4c033049cbc7efc55380922eb16c1c231307ae9)


Kemna_Walze-Gigant_8_126 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_126.jpg&hash=9594c12d4072969688abc7cc8b5393f19398103b)


Kemna_Walze-Gigant_8_127 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_127.jpg&hash=2e7ef204191cbf4127938d1e407ddb47a611d23d)

The weight of the wheel was reduced from 750gr. on 350gr.

Kemna_Walze-Gigant_8_128 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_128.jpg&hash=8608c177e5b25950485e0030361af86fb2b8da8a)

Gorgeous. -- Russ

So nice as such a small centric exciting vise is, but I must confess that the processing time per wheel was much too long. I could work only with 0.3 - 0.5mm depth at 750mm feed with a 6.0mm cutter. For larger values, the vise wanted to vibrate. Also, the surface in the X and Y direction was slightly different - the two steel axles are indeed braced against each other, but for larger strengths, another vice is needed.

Long story short:
Since I have had no suitable lathe tool for brass, I had chosen the milling machine yet. With my tungsten carbide insert lathe tool, the surface was just ugly due to the wrong grinding angle for brass. A friend lent me a suitable lathe tool. So I could do all the work on the lathe. It's just more fun with the right tool.

The front roller wheel consists of two elements. The two rollers are mounted with ball bearings on a 3.0mm shaft. They can rotate freely against each other. For example, no differential is needed when cornering.

Kemna_Walze-Gigant_8_130 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_130.jpg&hash=3f3622384d542ae4c492dc776c6137e099f2b12d)


Kemna_Walze-Gigant_8_132 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_132.jpg&hash=e1c749c0462072fb2712608ba1047a20d4d3fdc0)

The caps for the roller wheels were machined from 1.0 mm brass. The small round cover discs were soldered into the 0.5 mm deep milled pockets. A bolt and nut brought everything into a model look.


Kemna_Walze-Gigant_8_131 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_131.jpg&hash=7999d8a0394853fde2d99d4dab56d10204a16628)


The printed strap for the front wheel pair received a 2.95 mm bore and has been reamed with a reamer suitable. So an old broken 3.0mm cutter can serve as axis.


Kemna_Walze-Gigant_8_133 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_133.jpg&hash=7221bdfc7d197c9c816707ce4786fb6548653952)




A few days ago I got a very nice PN from Gerd (a colleagues at Buntbahn forum).
He had discovered an original of a Kemna Gigant roller close to him. He took a few photos and has kindly given me these for use! Thank you again in this way, Gerd !!!


He was able to clarify two more "open" questions:

1) Has the giant roll a differential or not? - YES, this roller has a limited slip differential!

Kemna_Walze-Gigant_8_141 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_141.jpg&hash=0e2c56269473bad685f64c8d3da49ef9ae6a4730)
photo taken by Gerd (Kohleheizer)

Kemna_Walze-Gigant_8_142 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_142.jpg&hash=98b92cfb7fd34f70dd895d4c6109c62b162dc696)
photo taken by Gerd (Kohleheizer)

Kemna_Walze-Gigant_8_145 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_145.jpg&hash=5ef124912917946040c97dd80d5fb933959eb8ec)
photo taken by Gerd (Kohleheizer)


2) Is there a suspension? It was not to be seen!


A few more views of the roller manufactured by the company Alfred Hagelstein in Travemuende:

Kemna_Walze-Gigant_8_136 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_136.jpg&hash=b697e5c8801b0de0a9583285384ad76b1694f8c7)
photo taken by Gerd (Kohleheizer)


Kemna_Walze-Gigant_8_134 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_134.jpg&hash=a8082bc663fcc0594aae9c5e8ad9ac6334342982)
photo taken by Gerd (Kohleheizer)


Kemna_Walze-Gigant_8_137 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_137.jpg&hash=54045c4b8916baa95b6d148987dfae21158b0148)
photo taken by Gerd (Kohleheizer)

Kemna_Walze-Gigant_8_138 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_138.jpg&hash=3de75453c371a9ba335f56c40e72e199098929c6)
photo taken by Gerd (Kohleheizer)


An interesting detail is certainly the ground ripper:

Kemna_Walze-Gigant_8_143 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_143.jpg&hash=1bdf91117ced708e7924c6b4ab9b20c7eb6b46fe)
Aufnahme von Gerd (Kohleheizer)


Meanwhile, I have visited the roller itself.
Armed with a ruler and camera, I was able to discover many missing details.

If you want: click here (http://www.buntbahn.de/fotos/showgallery.php?thumb=1&cat=9402&si=&perpage=80&sort=2&stype=&ppuser=2903)

What a great find, and in good condition too!

The quality of your progress remains top notch. -- Russ

@Ray
I'm always happy if I get more and more informations

@Russ
You make me a bit embarrassed, it's just normal model making.


As we had met with Helmut recently, we talked about different ways to colorize the steel tire of the roller.

In addition to the proposal to turn off the outer edge and replace it with a stainless steel tire, a more elegant solution emerged:

to nickel electroplated or chemically (https://en.wikipedia.org/wiki/Electroless_nickel_plating)!

Helmut lent me a kit for electroplating nickel. Thomas Heyl has described on its website the procedure very well: click (https://www.themt.de/mt-0450-chrm-49.html)
In this case, the coating is indeed quickly visible, but the abrasion resistance is probably not as strong given.

Thomas E. then proposed electroless nickel plating. Thanks for the tip - the result is really great!

I was lucky, a supplier right next to me had just re-scheduled his nickel bath. So it took only one day and I had a nice sea water and abrasion resistant surface.


Kemna_Walze-Gigant_8_289 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_289.jpg&hash=714f2ef1de3599460c1d71fd74ded3c4d3ed5e62)


If the wheels are painted and aged later, you will see only metal and no golden brass shining through in those places, where eventually the color dissolves.
The inner edge and the inserted brass plates should be painted red.


Helmut wrote on 04.20.2018 at Buntbahn forum:

QuoteFor that real rollers have the ability to tilt the axis, so that the wheels show even on curved roadways effect.

Have you ever thought to realize this in the model?

In the meantime, I got a brochure scan from the former manufacturer of the HATRA Gigant 8 with the decisive hint! (Thank you for your kind support!)
And no, I will not replicate this double swing axle in the model!

Hatra_Gigant_Doppelschwingachse-02 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Hatra_Gigant_Doppelschwingachse-02.jpg&hash=2c1b42c4608365f83b19b2276d64ab2bc27cd6c3)
Copyright: https://www.hatra-baumaschinen.de


Hatra_Gigant_Doppelschwingachse_01 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Hatra_Gigant_Doppelschwingachse_01.jpg&hash=294869098bcb13be014d1bfaea9edd2106a2a462)
Copyright: https://www.hatra-baumaschinen.de


Hatra_Gigant_Doppelschwingachse_03 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Hatra_Gigant_Doppelschwingachse_03.jpg&hash=9d1d7e0f4e3d5949ea79674720f25a9e7267f10d)
Copyright: https://www.hatra-baumaschinen.de



At the original roller I could make a few shots: here (http://www.buntbahn.de/fotos/showgallery.php?cat=9402&si=&page=2&sort=7&perpage=80&password=&ppuser=2903&stype=) und here (http://www.buntbahn.de/fotos/showgallery.php?cat=9402&si=&page=3&sort=7&perpage=80&password=&ppuser=2903&stype=)

When measuring the width of the chassis, I found that my model was drawn exactly 2.0mm too narrow.

Kemna_Walze-Gigant_8_181 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_181.jpg&hash=4bccd872d7c6094621d8a15c887a60deeb9819e7)


So I have changed the files... with the result that the old unrolling of the housing was 1.4mm too short now!
Since you are now a confidant: wink: .... it will be milled again.
Indeed you can say that you do not see the 0.7mm per side ..... That may be true, too .... but I know that ... As long as I have the opportunity to improve on my possibilities, so I'll do it.
But the larger width has the advantage that I have 2.0mm more inside. So I can use a stronger and wider battery. To be honest, that was the reason for redrawing.

Between the housing and the rear rolling wheels, there is a metal cover.

Kemna_Walze-Gigant_8_212 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_212.jpg&hash=60310f812407c75e2b4bad0cea09c79a136dd805)


It probably served as protection when tilting the axles.

Kemna_Walze-Gigant_8_264 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_264.jpg&hash=454fbb92e1bafabd756415fa1e223d86125d88b8)


Kemna_Walze-Gigant_8_266 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_266.jpg&hash=a44da58176fe6cd59084589d6f8fc25d91bf63e1)

Kemna_Walze-Gigant_8_287 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_287.jpg&hash=bfc275fead5c7468dc8e5acabd3a0dfc9f3b2288)


Kemna_Walze-Gigant_8_288 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_288.jpg&hash=a97390b2ea96e2d4826c131ec70781738281a3a9)

You are rebuilding some parts because of a 2mm discrepancy on a 1:22.5 scale model? The only one who would know it's too narrow is you!

As for electroless nickel plating, it emerged in the late 1970s-early 1980s to protect pistols and rifles from water and corrosion. For a while, some expensive and sophisticated target rifles and handguns had such plating. Soon, though, stainless steel technology improved and they found ways to make stainless parts harder and more durable. That pretty much ended electroless nickel plating on firearms.

Russ

Very cool project.
The documentation of this interesting piece of technology history is valuable in itself.
And your experimentation with modelling techniques is both entertaining and educational.

Thank you for sharing!

Very interesting. I'd never heard of electroless plating before.

The drive unit is located in a separate subframe.
Compared with the  first drawings (http://www.buntbahn.de/fotos/data/9402/2903Kemna_Walze-Gigant_8_067.jpg), it was modified and supplemented by two engine bearer plates.


Kemna_Walze-Gigant-8_292 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_292.gif&hash=bd2c4b1812458386d76c7575c5c86d273b0c5634)


Kemna_Walze-Gigant-8_293 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_293.jpg&hash=9dec654a3b2fc0500e27297d7dc0fad5dcbd4bc5)


Kemna_Walze-Gigant-8_294 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_294.jpg&hash=06b3f29cb3575b4910e3ae20fcabb09997a495c0)


In order to mount the parts exactly parallel, I have milled small Pertinax gauges.

Kemna_Walze-Gigant-8_295 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_295.jpg&hash=0e1d2f323a710c60bc7af3b26022d0d5e06da5a3)


Kemna_Walze-Gigant-8_296 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_296.jpg&hash=0002c6546d224486afbfe1e1938e127e13429ceb)


Kemna_Walze-Gigant-8_298 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_298.jpg&hash=a2b9482279754d5ca54600ff2e7f065999aff657)

When I came back from my last business trip, two packages lay on my desk.

The first package came from Shapeways and had two small black bags with wheel covers for the rear roller wheels.

Although I ordered them as "brass raw", they came highly polished.

Kemna_Walze-Gigant-8_299 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_299.jpg&hash=0ebac1c0e8a49ba9448a1920920bee3b38a6ec8e)


Kemna_Walze-Gigant-8_300 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_300.jpg&hash=ea140a0d7c8f0f677925070e13fce32760b41edd)

Originally, I wanted to make the wheel hub on the lathe and solder the small lettering as an etched part.

But then I let it print in the  lost wax casting.  (https://www.youtube.com/watch?v=9uxE_r9kEE8). I was very curious if the font is clearly legible - it is only 0.2mm thick.



At the beginning, I created and dimensioned a 2D sketch.

Kemna_Walze-Gigant-8_304 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_304.jpg&hash=a3e1eef7dd945c2964a0efa745831de35fb33969)

Then the sketch was rotated 360 ° around the central axis to create the 3D model.

Kemna_Walze-Gigant-8_306 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_306.jpg&hash=b601c1bf384d48e0b844190fe716fa031fadffaa)


Afterwards I put a new sketch plane on the surface of the wheel hub and copied in a scaled photo (1: 22.5) as background.

Now the outer contours of the black ring and the writing were redrawn and then extruded everything up to 0.2mm in height.

Kemna_Walze-Gigant_8_290 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_290.gif&hash=304c442d205c884addcb7d8d237ad4880b1ebae9)

Incidentally, the lettering stands for Julius Kemna (https://www.kemna.de/content/historie.php).

Kemna_Walze-Gigant_8_291 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_291.jpg&hash=270a0c760ce78c0685796108c5b3aa212b93f718)


Well, the second package had it in itself: Two small 7.0mm x 4.0mm shackles !!!
(The postage was more expensive than the content!)

Kemna_Walze-Gigant-8_303 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_303.jpg&hash=5168356991a5ea0177f1097bb6d4d7a01d8741fa)


Kemna_Walze-Gigant-8_302 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_302.jpg&hash=90809aeab6420f2d01d7c0d19d6692cb89daf1eb)

The parts look beautiful. Are you surprised that Shapeways gave you parts of such quality? -- Russ

Sweet!

Wonderful to watch the process , that front roller carriage is just beautiful ..... as are the rear wheel covers & lettering

Wow! I continue to be fascinated by this incredible project, both in terms of process and workflow as well as the final output.

I have a small project in mind for my train depot: a replica of an early Fairbanks warehouse scale, with some of the parts 3D-printed in brass. I would do the ABS prototypes on my cheap printer and send them out to Shapeways or somewhere for the final product. What you got from Shapeways looks pretty darn good and I was wondering what your thoughts would be on this.

Also, may I ask what CAD software you use? I currently use SketchUp for working with structures and Autodesk Fusion for components.

Greg

Thanks to all!l

@Greg
The quality of Shapeways (or similar providers) can only be as good as the template.
For a cheap printer, the print resolution is usually very rough. That means you can see clear steps.
I created a stl-file (highest resolution) in my Cad program (Inventor) and sent them to shapeways.
Within 10-14 days I received the finished product.


Meanwhile I had milled the outer shell a second time and also made new bending templates from MDF for the larger radius.
When milling the new brass plate, I noticed that the same cutter (as before) now pulled up the edges ..... MS58 brass was ordered ..... but the behavior was more MS63 brass...
After annealing the brass plate with the flame, I was able to bend the material much better than the MS58 plate.
Previously I had removed the slightly elevated level of the edges with a sandpaper file.

For further assembly of the roller I have milled small lessons from hard paper again.

Kemna_Walze-Gigant-8_308 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_308.jpg&hash=5371a1b5c484ac1c38a88571580dae8c267f454e)


Kemna_Walze-Gigant-8_309 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_309.jpg&hash=af6362a8af5bdd7f46f2dde6a36590f0e64d69ee)


Kemna_Walze-Gigant-8_310 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_310.jpg&hash=0518b8f271b22c470573f9b0949555be38e6c12a)


Kemna_Walze-Gigant-8_311 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_311.jpg&hash=672e5454bea4da855f05a9ef4928d4b0bb6b7526)


Through corresponding recesses I can fix the exact position, as in this example, the rear cab floor plate to the two side cheeks. To keep the 0.5 mm supernatant of the yellow side plates during the soldering by hand, I was too unsure.

Kemna_Walze-Gigant-8_312 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_312.jpg&hash=6d66c136e9e8e2c60c7c6c66de3eb4d0f8ea5e5d)


Kemna_Walze-Gigant-8_313 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_313.jpg&hash=275591fc532b8130d87193900a92dcd8b5e9ab58)


Kemna_Walze-Gigant-8_314 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_314.jpg&hash=b3535bb65a12700f64e9d673b860bcb1e8c09f0d)


Kemna_Walze-Gigant-8_315 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_315.jpg&hash=bb8124b43afbeca40803befae6d5a976ef74413a)

The floor base plate itself was slotted on both sides. For this I have grooved the upper side first. The four 2.0mm brass pins served to accurately position the back side.



Kemna_Walze-Gigant-8_307 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_307.jpg&hash=5845d6cf7aa05be983f838e0fe6d06408b22aa91)

Well, that worked out nicely. -- Russ

The resistance soldering tool just helped to solder the parts together in the hard paper gauge.

Kemna_Walze-Gigant-8_316 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_316.jpg&hash=c7281563221ab4236799587db4dca86359611303)


Kemna_Walze-Gigant-8_317 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_317.jpg&hash=c8e2fb65da57c67f557b41bb6d1d71151389c5a2)


So far, everything fits together.  :) :)

Kemna_Walze-Gigant-8_318 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_318.jpg&hash=1c6a26645518a9ace7d62c7d371da63bedafe70f)

great job Frithjof look forward to the next post Cheers.

Impressive. -- Russ

With the roller it goes on only slowly.  

Two inner cover panels were merely milled from 3.0mm brass.

Kemna_Walze-Gigant-8_319 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_319.jpg&hash=203008dde3de0faa344e26dc47a1126bbb6561aa)


Kemna_Walze-Gigant_8_267 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_267.jpg&hash=83ffe3a7c9e48ef1ead6a33f8bd7270594c787c5)


Slowly, the first printed small parts come in:

Kemna_Walze-Gigant-8_320 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_320.jpg&hash=2a93b44b0edaf6a56e9808a54450d67859cf4960)


Kemna_Walze-Gigant_8_157 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_157.jpg&hash=7503c744959c7994a26fd21c1c2a40a69457683b)

When comparing the last two pictures I noticed a mistake on my part ...grrr......



Well, the handle sits exactly on the opposite side - has happened.

Kemna_Walze-Gigant-8_324 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_324.jpg&hash=4bccaf593408e19cddc82ba334738082fd1a509c)



Kemna_Walze-Gigant-8_321 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_321.jpg&hash=eebd50a4ad687216db749c7ade70f876517f2da4)



Kemna_Walze-Gigant-8_322 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_322.jpg&hash=a27852c9d47eb52f68466d79cdf0e2f4cf0b0a4b)


Kemna_Walze-Gigant-8_323 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_323.jpg&hash=84f42839b728d731287eb68c39a232f4acb51ca7)

Given this, and especially since I need two of these handwheels, I have again invested € 14.40 / per wheel for two raw brass lost-wax parts.

All parts I have previously ordered as raw came gold-shiny therefore free of extra charge.
The steps of the often quite coarse resolution (see the oblique connection on the small casting on picture 320) are usually not visible ... but the parts themselves are a little bit smaller - for example: the wheel diameter should be 17.8 mm ...

Kemna_Walze-Gigant-8_325 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_325.png&hash=0005fa46dd534293306d367b79072c425c340449)

...it has 17.45mm to 17.54mm - about 1.5% - 2.0% less.


According to information from another printer provider, the shrinkage behavior in lost wax casting is negligible.
Soon I will have a comparison, if I get from there new parts.


After 10 days I got the new handwheels.

Kemna_Walze-Gigant-8_333 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_333.jpg&hash=4be8e96d5cbb75bcce53d626f153b25010317a62)

left: sandblasted new wheel, the levels of printing are no longer visible to the naked eye. To keep the wheel during sandblasting with the big gloves better, I have tied it to a 0.3mm wire.
middle: the unfinished second part
right: the old hand wheel with the toggle in the wrong position.

The rear "coupling u-pile" is also ready for installation:

Kemna_Walze-Gigant-8_332 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_332.jpg&hash=f1631c39bf532e2e2a163c8a7d31fbe0ac0de865)


Kemna_Walze-Gigant_8_155 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_155.jpg&hash=fa4a36d8db5ad4229fe6280831a33e6bd4554e46)




For the numbers "1, 0, 2, 3" on the lever rack I used the font type "ROMAN D". Although "bold" has been activated, the four numbers appear extremely thin.


Kemna_Walze-Gigant-8_326 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_326.jpg&hash=e037726258c8a31fec63d47abf24525583be5b16)


Kemna_Walze-Gigant-8_327 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_327.jpg&hash=9a3f3615ec968d90fd5e00edb1db4e69b6890f61)


Kemna_Walze-Gigant-8_328 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_328.jpg&hash=e7bf344eaf4a081aad9c21a6dec561bd05f2a8b3)


Kemna_Walze-Gigant-8_329 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_329.jpg&hash=72394362447fa79d7e076ab6d980caaadbdeae3e)


Kemna_Walze-Gigant-8_330 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_330.jpg&hash=324c193ffdbb471d776b72db36b6f06fc7f0d4e0)


Kemna_Walze-Gigant-8_331 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_331.jpg&hash=b1a4489d9cb07c43fae25b133a6444d6126438e6)



Volker helped with modified letters.

The result is a broader appearance of the only 0.9mm high numbers.

Kemna_Walze-Gigant-8_334 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_334.jpg&hash=54343fc1dc5e324c3a7f8cef3f025f972f7ceb3f)
on the left the original font - on the right the new modification.


Kemna_Walze-Gigant-8_335 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_335.jpg&hash=a3a75e62234f38da3571419b2da0e7950f0567e8)

In a few days I will get the part in brass from wax-lost casting.

Kemna_Walze-Gigant-8_336 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_336.jpg&hash=b87ac596a219674be7edc456d82f3cf55e766d2d)





Yesterday something strange came to light!


Kemna_Walze-Gigant-8_337 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_337.jpg&hash=39a4927322e02c6dbed80e5dd9ae5600e1ec94dd)
...shit happens... :-)

It almost looks as if my router wanted to try as a 3D sausage printer.


It should be milled out from a 2.0mm brass plate only the bottom plate below the checker plates!


Kemna_Walze-Gigant_8_160 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_160.jpg&hash=10c4464801964889be738fa325974b1bb79c1f0b)


Kemna_Walze-Gigant_8_161 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_161.jpg&hash=62b5b5c95728cdb0974855e5c281c8979818826f)


Kemna_Walze-Gigant-8_339 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_339.jpg&hash=0e6f6e11207b2d842af5b51f429c41850edc03b0)


Kemna_Walze-Gigant-8_340 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_340.jpg&hash=2d2092c54d60ab2ba907270fe2c1f84838ac7445)


At second try it worked.

Kemna_Walze-Gigant-8_341 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_341.jpg&hash=dbb42aa212a82bc485890dee18d99d2e9dad9881)

Slow, steady, world class modeling. -- Russ

Quote from: finescalerr on August 25, 2018, 11:08:02 AM
Slow, steady, world class modeling. -- Russ

What Russ said!

Did you find out why the router went haywire?

Incorrectly, I used a 1.2mm drill instead of a 1.2mm cutter. I only noticed it when the drill broke off.

I had drawn the coupling plank 0.6mm longer to counteract shrinkage during 3D printing.

It fits :)

Kemna_Walze-Gigant-8_343 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_343.jpg&hash=e9f643794a9c8421d942326cfca88a9a758e40c6)


Kemna_Walze-Gigant-8_344 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_344.jpg&hash=77ab8240f8770d2addfc8c9fca98ce1577d39906)


Kemna_Walze-Gigant-8_345 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_345.jpg&hash=3c296a341155d573c6c5abea02a8510605e136f3)


Kemna_Walze-Gigant-8_346 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_346.jpg&hash=7e1767d8a5ec14b8d88e097affb8b04d9687e93c)

I want to make the middle hood area of the roller foldable - like the prototype.

Montage_Blechhaube_Kemna_01 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Montage_Blechhaube_Kemna_01.jpg&hash=38e52fbd0770fbbc8af4346b4fbb1959c36d19d1)


My first idea was to solder an 1.2mm tube to the 0.2mm side panels and then clamp them into a jig, to mill the mutual gaps.

Here is the fear that the only 2.0mm long and 1.2mm in diameter tubes do not join the movement too long.
Also, the brazing of the thin parts is certainly not really accomplish, without that the sheet burns up or rejects.

So Volkers attempt was a little more convincing as he visited me recently.

On the web, I found two examples very similar - only much smaller: click (https://www.tijio.com/de/d/kategorien/handwerk/modellbau/12142538806.html) and click (https://www.tijio.com/de/d/kategorien/handwerk/modellbau/12142476823.html).


Kemna_Haube_beweglich_01 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Haube_beweglich_01.gif&hash=9f93840f8c1701bba72c125c78a2046be36f9632)


Kemna_Walze-Gigant-8_354 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_354.jpg&hash=043c2f1e7fdbbb1bee3153915ebdd0090a86599a)


Kemna_Walze-Gigant-8_353 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_353.jpg&hash=9d93aba66dca2813ec39494defc86d4fea90bbd8)


Meanwhile, a colleague at Buntbahn forum gave a good hint!
He asked if it would not have been easier at the prototype to weld something like a piano band under the sheets.

I had only a few partial views of the hinge from the Kemna Roller in Herborn.
After I had assembled them in Photoshop and downscaled to 800px for the forum, although I could count the number of hinge sections ... only accurate details were not really recognizable on the piebald surface.


So I have inspected the original images again, and lo and behold ....

The side parts had been riveted to the hinges.

Kemna_Walze-Gigant_8_358 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_358.jpg&hash=cef45bfc51bec81ab1a71489da896675892c2dce)


Kemna_Walze-Gigant_8_359 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_359.jpg&hash=20f424482c20f01e0196c68568a8f254f10b92f1)


Kemna_Walze-Gigant_8_360 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant_8_360.jpg&hash=3cc23f69f53920ff5da468eba2056fb2bcb2f0c8)


At the Buntbahnforum Henner showed his way to make hinges. Contribution from 2011/11/24: click (http://www.buntbahn.de/modellbau/viewtopic.php?t=9905&postdays=0&postorder=asc&start=20).



Far more difficult will be the tiny beadings that are in the curve of the front hood cover!

On the web I could find some shots in the "naked" state:

(https://scontent-frx5-1.xx.fbcdn.net/v/t1.0-9/51568354_242330759987822_1651304471638048768_n.jpg?_nc_cat=107&_nc_ht=scontent-frx5-1.xx&oh=c44a6afa08d1b78a3f2ddc1d6c874cf0&oe=5CE15C68)
found at: https://www.facebook.com/196382207916011/photos/pcb.242331009987797/242330756654489/?type=3&theater


Kemna_Walze-Gigant-8_355 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_355.jpg&hash=63bf3a0e080cd1585c6f5d7d68c47aba560d4c53)


Kemna_Walze-Gigant-8_356 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_356.jpg&hash=e17d16818117ae0c50eae9d40ed13f0fda75d720)


Kemna_Walze-Gigant-8_357 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_357.gif&hash=5ac9185c62f716360dc1450639be88217837e0e7)

And then Peter showed his great solution with his depressed beadings.
Maybe you can set your picture here so everyone can see it?

I know you will create those details and I know they will look perfect.

But you're crazy.

Russ

Sometimes it's fun to be a bit crazy ;)

On 2019/08/25 I wrote:

QuoteIn a few days I will get the part in brass from wax-lost casting.

I forgot to report the result.

After my order was accepted in Brass-Raw (Professional plastic was immediately rejected because of too low material thickness), 3 days before the confirmed delivery date a rejection of Shapeways came: ... "too small wall thicknesses".

The order at another provider was delivered within one week.

After removing the still visible pressure levels from the lost-wax plot with a small sander and sandpaper file, the tiny numbers (letter height = 0.9mm, grandeur 0.2mm) were still readable.

Next time I will have the wax plot of such small objects created by another provider, Volker had very good experiences ... maybe a bit more expensive, but the rework should be minimized significantly.


Kemna_Walze-Gigant-8_348 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_348.jpg&hash=538efd39b18e435c3d2e07c9b5d7d40d6f176853)


Kemna_Walze-Gigant-8_349 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_349.jpg&hash=f9afb5c4bee3bddc0b4077db1d8d48fd037cc9d9)


The parallel delivered front hood rounding I sandblasted only.

Kemna_Walze-Gigant-8_347 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Kemna_Walze-Gigant-8_347.jpg&hash=fa38afd2eaab361095223d525a5eb65c52881397)

Quote from: fspg2 on March 09, 2019, 12:40:14 PM
And then Peter showed his great solution with his depressed beadings.
Maybe you can set your picture here so everyone can see it?

By no means I want to hijack this thread - here the two pictures (front/rear).

(https://images46.fotki.com/v677/photos/4/3824994/14463210/IMG_20190308_194836-vi.jpg) (https://images34.fotki.com/v1623/photos/4/3824994/14463210/IMG_20190308_194902-vi.jpg)

Gentlemen, the parts each of you produced turned out superbly. -- Russ

Wow!

Peter, thank you for the solution you showed with the great result! Let's see if I can do it that great one day.


In the meantime a little more time has passed than I actually wanted, but there were and are a few more things besides the hobby.

Yesterday evening I tried to mill the hinges for the swiveling hood of the Kemna Gigant 8 roller.


Scharniere_0,8mm_Loch_02 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_02.jpg&hash=804de2585ca5fd667f0aa78448aacae4b93dbb4c)

The eye has a diameter of 0.8mm, the outside diameter is 1.2mm - this results in a wall thickness of 0.2mm.


Scharniere_0,8mm_Loch_03 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_03.jpg&hash=d15abc1829df8611080e26f09bba45f03a35429c)


I milled these parts from existing 2.0mm MS58 material.


Scharniere_0,8mm_Loch_05 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_05.jpg&hash=48bcd7b0d093c57c049d42f13a57553c08e52dc2)


Scharniere_0,8mm_Loch_06 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_06.jpg&hash=e8ccb919e0bd2a6cebe742130c9b85cb5602ebcd)


I don't really like the proportions yet!
The outer diameter could be brought to 1.0mm and the width of the individual hinges would have to be approx. 0.2mm wider.

Let's see if I can try again with 3.0mm brass.

To do this, I would first have to mill a pocket to bring the material to 2.2mm thick. Then I could drill the holes in the material with a 0.5mm drill (instead of 0.8mm).
Then it will be exciting to see whether a slightly longer 0.5mm milling cutter mills the outer contour into the brass just as well ...:?:

The 0.5mm milling cutter I have used so far has a cutting length of 2.2mm. This length is no longer sufficient to plunge approx. 0.2mm into the material below.


Scharniere_0,8mm_Loch_07 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_07.jpg&hash=a63d8982d1e82a6ca1b8e929bdcb2bc4e7d91484)

Ah, here we go! I am already curious, there is always a lot to learn.

Bernhard

Maybe you will do better next time but it already looks quite good. -- Russ

That's really good work! Is the rollers internal combustion engine also going to be operational? :)

Thank you for the kind comments.

So today I started a new attempt.

For this purpose, the eye was reduced from 0.8mm to 0.5mm, so that I got an outer diameter of 0.9mm, the width was widened from 2.0mm to 2.2mm.


Scharnier-Vergleich_1,2mm_zu_0,9mm_1 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharnier-Vergleich_1_2mm_zu_0_9mm_1.jpg&hash=74a45d4297534b070c9c5f98ddbb4f1c83175275)


From a purely visual point of view, the hinge has come much closer to the original by reducing the outside diameter of just 0.3mm!


Scharniere_0,8mm_Loch_10 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_10.jpg&hash=0b3afd4dba581d8f641342fd3e01b2f712d368b2)



A recess of 0.8 mm was milled in 3.0 mm MS58 in order to obtain a residual material height of 2.2 mm.

Then the 0.5mm holes were drilled. A 5.0mm long 0.5mm milling cutter was used for the outer contour.


Scharniere_0,8mm_Loch_11 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_11.jpg&hash=ef02897f9bc913f9c54a0437aea7d0e1c9e24751)



With such thin cutters I usually proceed cautiously,  too often a mishap has happened to me - too fast, too deep ... crack!

In between times I used the compressor to blow open theslots. The last pass was milled through and the MDF material was scratched 0.2mm deep.

Scharniere_0,8mm_Loch_12 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_12.jpg&hash=182e4df7c23c02620d10903598f53dbc086b9917)


The two following images refer to yesterday's milling in the 2.0mm brass material.


Scharniere_0,8mm_Loch_08 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_08.jpg&hash=7fe08b66269226f31b85f085f410c822c9119264)


After the last pass, the milled part got stuck in the plate by small retaining bars on the lower beam. I then separated everything with a thin craft knife.


Scharniere_0,8mm_Loch_09 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_09.jpg&hash=7b35ea6ae5bd06b19a6bbcf0c54314ae863cf904)


10 hinges in one go takes about 40 minutes now.


Scharniere_0,8mm_Loch_13 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_13.jpg&hash=5c4b84f9b4c8ed248443445f0ac8c482c9e57327)

Here again the comparison of the two hinge variants.

Scharniere_0,8mm_Loch_14 (fspg2)
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.buntbahn.de%2Ffotos%2Fdata%2F9402%2F2903Scharniere_0_8mm_Loch_14.jpg&hash=b9d83cf3a2e2c2e33a8525dc49d86f852f7b1d29) 

The difference is more visible than I expected. Nice job. -- Russ

Holy cow! I thought the first batch was impressive, then you managed to improve on it!

At the front of the Kenna Gigant 8 there is a curved front panel with an "inspection flap" which has a round, reinforced edge.

The first consideration I didn't really like - I wanted to mill a 0.3mm recess in a 0.5mm thick MS58 sheet with a 1.0mm ball end mill to solder a correspondingly bent 1.0mm wire into it.

My first attempt at making everything from a 1.0mm MS58 sheet was not crowned with success. I had milled the plate down to 0.5mm thickness with a 3.0mm router bit. Only the 1.0mm thick edge of the lid remained and was wound inside and out with a 0.5mm quarter round cutter.

Revisionsklappe_Kemna_Gigant_8_06 (fspg2)
(https://www.buntbahn.de/fotos/data/9402/medium/Revisionsklappe_Kemna_Gigant_8_06.jpg) (https://www.buntbahn.de/fotos/showphoto.php?photo=134270)
 
It doesn't look good in the sharp side light. What happened?
I usually use Gudy870 (https://www.schmedt.de/gudy-870-doppelklebefilm-transparent-sehr-duenner-traegerloser-klebefilm/33470000.B) to glue my sheet metal to be machined onto MDF boards, which are then attached to the router.
I had done the planing of the surface in small increments (0.2mm, 0.2mm, and 0.1mm in succession), relaxing the sheet so that it curved slightly upward from the center, thus removing more of the material during the subsequent routing passes. In the middle, it is now only 0.15mm full 0.5mm thick.
I had also used an old remnant piece here, where the milled out piece was not fully glued on.

What ultimately led to success?
Two parts were milled. A 0.5mm MS58 sheet received the oval cutout. The lid with edge (milled from 1.0mm material) will be soldered into this later.

Revisionsklappe Kemna Gigant 8_01 (fspg2)
(https://www.buntbahn.de/fotos/data/9402/medium/Revisionsklappe_Kemna_Gigant_8.jpg) (https://www.buntbahn.de/fotos/showphoto.php?photo=134260)

Since there was still a leftover piece of 5.0mm MDF on the milling machine, I quickly milled a small bending gauge.

A straight lower part is followed by two different radii.
The bending gauge itself has two radii, each reduced by 5.0mm, so that the annealed sheet is overbent and can then spring back to the desired bend.

Revisionsklappe_Kemna_Gigant_8_08 (fspg2)
(https://www.buntbahn.de/fotos/data/9402/medium/Revisionsklappe_Kemna_Gigant_8_08.jpg) (https://www.buntbahn.de/fotos/showphoto.php?photo=134272)



Revisionsklappe Kemna Gigant 8_02 (fspg2)
(https://www.buntbahn.de/fotos/data/9402/medium/Revisionsklappe_Kemna_Gigant_8_02.jpg) (https://www.buntbahn.de/fotos/showphoto.php?photo=134263)

Revisionsklappe Kemna Gigant 8_03 (fspg2)
(https://www.buntbahn.de/fotos/data/9402/medium/Revisionsklappe_Kemna_Gigant_8_03.jpg) (https://www.buntbahn.de/fotos/showphoto.php?photo=134264)

Revisionsklappe_Kemna_Gigant_8_05 (fspg2)
(https://www.buntbahn.de/fotos/data/9402/medium/Revisionsklappe_Kemna_Gigant_8_05.jpg) (https://www.buntbahn.de/fotos/showphoto.php?photo=134269)

I had a phenomenon after annealing the 0.5mm sheet: The width of the oval cutout had decreased from 25.0mm to 24.9mm. To be able to solder in the lid, I have to file a little.

Revisionsklappe_Kemna_Gigant_8_07 (fspg2)

(https://www.buntbahn.de/fotos/data/9402/medium/Revisionsklappe_Kemna_Gigant_8_07.jpg) (https://www.buntbahn.de/fotos/showphoto.php?photo=134271)

Almost no other modeler in the world could match your results. -- Russ

Nice to see that this project is going on as well. As always, it's interesting and inspiring to see which method leads to useful results.

Bernhard

Fascinating!

your works are carried out with great finesse and your templates inspire me for my future constructions.

How much over bending do you allow for spring back?
 
The same idea without spring back allowance can be used to bend polystyrene in concert with an oven.  Most importantly done when the wife is out of the house.