Building radial couplers by stereolithography

Radial coupler with radius bar (red) and drawbar (orange)

Functional radial couplers in H0 scale are rare to find as spare parts and hard to built from scratch. So it was natural to engineer them within the 3D print project. Weighting pros and cons, I decided that the coupler mount must be part of the car body and not of the frame. For two reasons: the radius bar is positioned close to the buffer, and the drawbar support close to the doorsteps. Both are part of the body shell.

I designed a drawbar who has a little nose who is overrunning the radius bar under the buffer. The general geometry is strictly to scale. As separate small parts cannot be 3D printed, I integrated the coupler inside the monotlithic car body as internal bars, avoiding warping of the body during printing. They must be cut out of the shell and sanded a little, together with the radius bar. Screw holes are pre positioned.

The production model of the wooden combine -  to be released soon - will have two coupler bars per shell. One is ready for Kadee NEM coupler heads, the other is spare.

2 drawbars are "cast" in the carbody
The coupler bar is working well with trailers, even in push mode through S-curves, despite the tendancy to jackknifing. This radial coupler will be mounted to all my future models,  and the older box cars will be redesigned as well.


How not to loose control over your traction cars

CCCo Wooden Combine: Northern Indiana (green) and Terre Haute (red)
3D drawing is computer drawing. This means that you will meet a point where things will get out of control if you can no longer track all the trunks of your project properly. I am there...

3D printing is a tricky affair, and a minor error in one of the hundreds (or thousands) of elements will make the whole file unusable.

So I put things in order and separated the Cincicinnati Car Co.Wooden Combine into several parts :

- A common base used for all variations (grey)
- An additional pack for one given version (green, red, ...)

Now I have merged the Terre Haute version (red) and the Northern Indiana version (green) in one master file. For one print project, the common base (grey) plus one individual package is exported into an STL file. On both showed versions, the side walls, the clerestory windows, the pilot, the rear roof mat and the chimney are not the same or missing. As this car was built or rebuilt to so many versions for Indiana and Ohio lines, several dozen individual packs or sub packs could be generated.

This technique not only applies for the carbody, but also to the underframes, who had different arrangements.


Baldwin truck frames for the H0 wooden combine

Terre Haute, Indianapolis & Eastern Traction combine, front end with Baldwin truck
The Terre Haute wooden combines were equipped with Baldwin MCB trucks. The wheelbase was to be about 6'6" or 6'10", the sources are contradictory. I choose 6'10", or in fact 7", making the truckframes matching on a NWSL Stanton drive. Anyway, the difference would be invisible in scale H0.


Cincinnati Car Combine resin print model

Resurrected: The old beauty from Terre Haute Indianapolis and Eastern Traction.

When things get real

Today I got a shipping from Belgium. When you open the package, and the things that where before only on your computer screen are suddenly real, this is always like a shock. I.materialise did an impressive job - and I have made no major error in my drawings.

Only a short hour to put NWSL Stanton drives on the car, and he was ready for a photo session. Thanks to a moment of Indian summer in Paris the light was as good as the models. Flush and fuzz are not yet removed. All is nearly as it comes out of the box.


Detroit United Railway - the 25 Dollar brand

Detroit United Railway herald
The Detroit United Railway, according to the Street Railway Review, driven by "the desirability of having some distinctive emblem to mark the property, stationary and general literature of the company", once organized a public contest. This contest was won by a Mr. William J. Ryan who submitted the herald shown here and who has been awarded the $25 prize money. 

This happened in 1903, the golden years of Traction Lines, and the 25 Dollars were a considerable sum in this days. Translated to actual values, the worth could be situated in a range between  $659 (using the Consumer Price Index), or about $4360 (using Production Worker Compensation as indicator).

I don't know what use was made of this trade mark, and if it was displayed on their cars. But you can download the editable pdf file here,

(Source : Street Railway Review Vol. 13, No.4, April 1903)