Rollwagen no. 28 of the Plettenberger Kleinbahn in 1/22.5 scale

[Hydrostat]

Apart from trackage certainly rolling stock belongs to the Plettenberger Kleinbahn topic, especially the typical Rollwagen, which served to carry standard gauge cars on the narrow gauge line.

The prototype was made by a small engineering company Boecker & Volkenborn from Hohenlimburg. If you're interested in technical details and willing to use google translate, please read here at buntbahn: http://www.buntbahn.de/modellbau/viewtopic.php?t=11487.


Sammlung Wolf Dietrich Groote


Sammlung Wolf Dietrich Groote


Sammlung Gerhard Moll

Some of those wagons have been delivered to Plettenberg, the last ones around 1959. By chance we got the opportunity to search the then still existing archive of the company for drawings of the wagons which came insolvent some ten years ago. This was looking for a needle in a haystack for there were more than 40.000 drawings to be searched - without any catalogue or index.
  
The few reference points were some drawings' numbers from the former Hohenlimburger Kleinbahn's archive. Three times we went there and we were able to find out drawings of five consignments - and save them from ruin. Unfortunately the complete drawings' stock has been wasted meanwhile for no museum or industrial archive was willing to take it.

Fortunately we found a complete set of drawings for one riveted Rollwagen, which was delivered to the Plettenberger Kleinbahn in 1927. I don't want to keep this pic of our search from you:



It surely would be easily possible to build this wagon as a model, but I'm more interested in one of the last to PKB delivered, welded cars. Unfortunately we didn't manage to find drawings of the 8.7 m long cars, which are recognizable on some pictures - like this one of a little mishap:


Sammlung Albrecht Kühne

Maybe a metalworking shop in Plettenberg and the Kleinbahn itself built those cars using some parts of Boecker & Volkenborn. They got numbers 26 and 28. Perhaps the full order books may have helped, but it was a too high health risk to check them.



So I had to develop the welded car from the pictures and some features of the older drawings. My claim is the consequent implementation to scale - including wheelsets and some special construction characteristics.





Meanwhile the first parts arrived. The solebars are milled from tool steel. All milled parts are made by friends, based on my drawings.





The etched brass number plate is soldered to a notch in the solebar.



Some more parts like a seat, covers and mudguards are etched, too.



The webs of the front-end crossbeams fit to special grooves.





Those are the upper and lower parts of the crossbeams. The buffer duct is going to be a cast brass part.



Some parts for the bogies.





Ball joint for the pivot allowing vertical movement.



Wheel chock holes for the loaded standard gauge wagons.



Cheers,
Volker

[finescalerr]

Most satisfactory, from the research to the components. -- Russ

[artizen]

Beautiful work. Shame about the disregard for the history in those files though. I guess the room was very damp?

[Chuck Doan]

Beautiful work for sure!

[Ray Dunakin]

Incredible work, as usual!

Those cars are a very interesting solution to the problem of transporting standard gauge cars over narrow gauge tracks.

What is that white stuff on the file drawers -- mold, or some kind of mineral/chemical deposit?

[Hydrostat]

Most satisfactory, from the research to the components. -- Russ

Thanks, Russ. I'm glad I'd clear the bar.

Beautiful work for sure!

Thanks, Chuck.

Beautiful work. Shame about the disregard for the history in those files though. I guess the room was very damp?

Incredible work, as usual!
Those cars are a very interesting solution to the problem of transporting standard gauge cars over narrow gauge tracks.
What is that white stuff on the file drawers -- mold, or some kind of mineral/chemical deposit?

Thanks, Ian and Ray. It is mold and it's the result of a water damage that flooded the complete flooring for a few months. Yes, it is a shame that no one was interested and / or able to keep this stuff. But this is how time passes by. Mankind is not able to preserve everything. Unfortunately there's always something like changing fashions in peoples' minds about what was worth to be preserved and what not. I would give something to be able again to visit places like the abandoned, but still complete factorys or mines or brickworks of my youth. But everything has to go by in our country for it's 'to dangerous' or landscape has to be 'reinstalled'. Imagine they'd do that with the river Rhine castles.

Okay, back to modeling. It can be some kind of preserving, too.

Volker

[Hydrostat]

The first brass castings arrived:



Brake wheel:



Part of wheel chock:



coupler plunger:



Some words about the chosen process: The master forms were printed with a ceramic filled synthetic material by the same provider who made the white metal castings of my phone and lamp. We wanted to find out if it was possible to use those masterforms for the lost wax process - with one difference: Printing in wax and melting this print out to achieve a cast brass master form, which is cast in silicone or rubber means to have two steps loosing detail. I wanted to see if it was possible to make the rubber mold directly from the printed master form, which has to be mechanical and temperature stable enough for the process. Very fine master parts like the brake wheel will be destroyed during removing the mold, but the results are okay. We tried some H0 scale test pieces beforehand. 

Printed parts:






Mold:






Castings:







Cheers,
Volker

[finescalerr]

The castings are very clean. The process seems to have worked very well. -- Russ

[Hydrostat]

Hi,

there was some little progress with the coupler parts. They needed M2 threads which I cut manually. That was difficult because the cast material is a bit soft and tends to distort.




A model nut with splint was added.





Helmut tried to drill the 0.5 mm holes in nut and coupler via CNC but he broke a lot of drill bits. The jig he used didn't result in centric holes because the threads are always a bit out of axis.

So I marked the nuts and drilled couplers and nuts separately and manually. I fixed the nuts with CA on the coupler and drilled from both sides to the coupler surface. By heating the assembly the CA vaporizes and the nut can be removed. Then I drilled the coupler. That worked somewhat better, but it took one drill for three holes ...

Not so with the splints: Again Helmut had an ingenious idea. He milled two 0.25 mm deep grooves into a brass plate and added two 0.5 mm holes at their ends.





There one can insert a prebent 0.5 mm brass wire ...





... which then fits after some hammering on the back of the jig.





Then the wires can easily be sanded down to the plate's surface ...





... and look like that afterwards:





You then have to bend the wire around a broken 0.5 mm drill in the vice (I've got some now ).





Then press the wire with spiky pliers around the shaft and shorten them with a flat side cutter -





and one can mount the finished splint.








Cheers,
Volker

[artizen]

I love this stuff!

Keep giving us more delicious modelling to drool over!

[finescalerr]

The two of you are in the top tier of railroad modelers. Adequate. -- Russ

[5thwheel]

Volker.  I became lost on the part about casting the brass.  Is the brass cast in a spin machine like white metal or is the brass actually a compound looking like brass?  I used too do white metal casting. The mold looks like white metal mold material. 

[Ray Dunakin]

Truly mind-boggling work!

[Hydrostat]

Ian, Russ, Ray and Bill, thanks for your posts.

Volker.  I became lost on the part about casting the brass.  Is the brass cast in a spin machine like white metal or is the brass actually a compound looking like brass?  I used too do white metal casting. The mold looks like white metal mold material. 

Bill, it is brass. The rubber mold is used to make the wax parts for the lost wax process. The resulting investment material mold is used for the brass casting with a spin machine. If 3D prototyping is used usually the parts are printed in wax, then cast with brass in the lost wax process and this brass casting is the prototype to make the rubber or silicone mold for the wax parts. I wanted it the direct way with the 3D printed part as prototype for the wax part mold. Please feel free to ask, if my explanation wasn't understandable. Or my English .

Volker

[5thwheel]

Thanks Volker. Now it is more clear to me.  You are pushing the outer limits of model making. Really nice work. I follow your posting when ever I can.

Bill H