1:35 Bucket chain excavator Ertmer KB 1

[Bernhard]

Hello modelers

The next project I would like to share with you is the bucket chain excavator Ertmer KB 1. The model is made entirely of brass, should be functional and is still in progress.

[Bernhard]

First some information about the prototype.

Use and operation of bucket chain excavators
The basic principle of a bucket chain excavator is to dig the material to be conveyed with buckets attached to an endless chain. The excavated material is dumped in lorries next to the excavator. While the bucket chain runs continuously, the excavator moves slowly forwards and backwards on its track. If the slope angle becomes too steep due to the progressive excavation progresses, the tracks of the excavator and the light railway are moved away from the edge of the excavation. The tracks are therefore only laid on a leveled surface.
Only relatively soft materials such as clay, sand or gravel can be mined with a bucket chain excavator, because only the dead weight of the bucket ladder guarantees the pressure of the buckets.

[Bernhard]

Depending on topographical conditions, bucket chain excavators can work in low or high cut. In deep cuts, the levelling piece at the front of the bucket ladder levels the bottom of the pit.
(Sketche from http://dachziegelarchiv.de/seite.php?kat_typ=15&max=1&sei_id=28535)

[Bernhard]

In America in the 19th century during the gold rush large floating bucket chain excavators (dredges) were used for gold mining. Tony Beets brought two of them back to life in recent years as you can see: https://goldrush.fandom.com/wiki/Viking_Dredge

[Bernhard]

The Prototype

Manufacturer	Maschinenfabrik Willy Ertmer, Ludwigshafen, Germany
Type	KB 1 (the number indicates the size, 0 = small to 3 = large)
Serial No.	810
Year of construction	1947/1948 (Order placed Aug. 1, 1947, Delivered Jan. 12, 1948)
Drive	Three-phase electric motor with belt drive (leather belt)
Excavation capacity	14 – 22 m3/h
Dredging depth or height	Up to 6 m
Today's location	Feldbahnmuseum Wiesloch, Wiesloch, Germany

The machine was used at the Enzinger brickworks in Eiselfing near Wasserburg am Inn from 1948 to 1976. After that, the excavator stood unused for years, until it was finally completely ingrown by a dense forest. In October 2010 the excavator was recovered by club members and brought to Wiesloch. In 2012 the excavator could be repaired and rebuilt in its original condition.
The excavator is one of the last known operational bucket chain excavators of the 1940s in Germany. In terms of year of construction, it is probably the last of its kind.
Further information can be found on the website of the Feldbahnmuseum Wiesloch https://feldbahnmuseum-wiesloch.de/fahrzeuge-technik/baumaschinen/ertmer-eimerkettenbagger.html.

The following video shows the excavator idling: https://www.youtube.com/watch?v=qFwKiMqrjdI

Bernhard

[TRAINS1941]

Bernhard

What scale is this going to be??

It should be a fine looking piece of equipment when done.

Looking forward to your next post.

Jerry

[Bernhard]

Jerry, the model is 1:35 scale.
Bernhard

[finescalerr]

I look forward to seeing what you create. -- Russ

[Chuck Doan]

Very interesting project!

[shropshire lad]

Greetings Bernhard from a chilly corner of England . I shall be watching your build of the eimerkettenbagger with great interest as I have wanted one in this scale for nearly ten years . I do not have the skill or the patience to build one for myself , so I will just watch you build yours . Of course , if you fancy building two rather than one then I am sure I could find a home for the second one !

    Nick

[Design-HSB]

Bernhard very interesting and demanding project.

[finescalerr]

Nick, you probably have the skill. Anyone who can build a 1:35 structure brick by brick probably can build anything. -- Russ

[shropshire lad]

Nick, you probably have the skill. Anyone who can build a 1:35 structure brick by brick probably can build anything. -- Russ

  Not true , Russ . What Bernhard proposes to do is skilled engineering where as what I do is repetitive bodging of the highest order . There is very little comparison between the two types of modelling . But thanks for your vote of confidence .

    Nick

[Bernhard]

Nick:
Russ is right. I just started building brass models once, after having worked with "normal" 1:87 model trains for years.
However, this project is quite complex, so I will leave it at one piece. But if required I can serve you with many photos, a 3D model and a complete set of drawings.

[Bernhard]

Thank you guys for following the tread.

Next step is the construction.

In spring 2017 I made a trip with my friend Werner to the Feldbahnmuseum Wiesloch, which is about three hours by car from us. There we measured and photographed the excavator together.
With several sketches and over 250 photos as a basis, the question arose how a set of drawings could be created for the realization of a functional model. On the drawing board, as I learned 50 years ago, or with a 2D CAD? The best solution seemed to be to create a 3D CAD model. However, this was completely new territory for me. After some searching and comparing I finally decided to use the free software SketchUp for this. It is intuitive and relatively easy to learn. Many hours later I was the proud owner of a full-scale 3D model with all the relevant details.