Bottom chassis for LGB switch drive 1201 & 1206

These are replacement parts for LGB switch drive 1201/12010 (electric drive) & 1206/12060 (manual drive).

These are the bottom chassis of the drive mechanisms.
Other parts can be found here:
- Switchdrive custom lid
- Cable junction box

The reason to create these is that I bought a double slip diamond crossing kit from Modellbau-Werkstatt Bertram Heyn (https://www.modell-werkstatt.de/kreuzungs-weiche-r3-2-x-22-5). I want to motorize this with LGB electric switch drives. The problem is that the mounting points on the switch drive are made for LGB railroad sleepers/ties. The sleepers in the kit are shallower, so the mounting points don't fit.

I could either saw/file down the mounting points (as described in the kit's building instructions), or I could create a replacement bottom shell with shallower mounting points - and that is what I did.

The SCAD file has the code to create the bottom shells for both 1201 and 1206. Each has an optional parameter to define a custom height for the mounting points. 1206 has also a seconds optional parameter to give it extra height - this is needed in this case because the drive rod of normal 1206 is too low for the double slip.

The SCAD file references the library af-basics.scad which can be found here: https://www.printables.com/model/175914-openscad-library-for-more-basic-shapes

The STL files are:

• lgb_switchdrive1201bottom.stl - normal bottom shell for 1201
• lgb_switchdrive1201bottom_flat.stl - bottom shell for 1201 with shallower mounting points for the double slip
• lgb_switchdrive1206bottom.stl - normal bottom shell for 1206
• lgb_switchdrive1206bottom_flat+1.stl - bottom shell for 1206 with shallower mounting points and 1mm extra height for the double slip

The photos show how the interior mechanics, lid and screws of the original LGB 1201 and 1206 are simple put into & onto the printed parts.

The parts are printed in grey Prusament PETG with 0.3mm layer height and 3 perimeters. I lowered the nozzle temp to 220°C after the first layer to reduce stringing. I advice to NOT use PLA because it might (will) deform in direct sunlight.

Update 2022-09-27:

I increased the clearance for the magnetic core by 0.4mm length-wise to accommodate older style drive mechanisms.
The SCAD file and both STLs for the 1201 bottom chassis are updated.