... preferred "universal" format for 3D printing. There are many slicer programs that take STL files and produce the Gcode to drive the actual printer. TurboCAD Pro creates solid models (rather than surface models) and the file format is proprietary. It claims to be able to output in the following formats but I do not know to what extent any of them, other than STL, would help. I can post examples if you think any of them would be better. I'm not too optimistic but it's worth a shot. 2983_081235_570000000.gif Cheers! Andy posted: 8 Jul 2018 17:52 from: Hayfield I have tested the chairs with C&L HiNi rail. I can only get C, E& F to thread, E being the easiest but in reality still far too stiff, I also tried some old PSM rail which wasmuch the same. I tried a switch rail (one side filed away) it was still stiff, looking closely at the rail one side of the foot of the rail is higher than the other, though that ...