The file 'OO/HO TRACK PENCIL HOLDER MKII 3D Printer Model' is (stl) file type, size is 586.2KB.
I could not help myself when I made the previous version I was thinking of doing this, but took the easy way out, and because of the interest in the MKI http://www.thingiverse.com/thing:2025266, here is the MKII.
The number of times I have had to trace along a piece of track to mark out where I want to lay the underlay, or marking out the curved form-work to lay the track.
Of course one does not have a set of radius curves of every size so this simple device joined up with the OO/HO FLEXITRACK CURVE FORMING CLAMPS in http://www.thingiverse.com/thing:2023001 you can make a radius template any size you like, and is not limited to model railways uses either.
The pencil needs to slide easily in the holder and may need a bit of extra weight added.
Wheels are on a 2mm axle, but may need changing to suit what you have lying around
TRACK-PENCIL-HOLDER-BODY.stl | 1.1MB | |
TRACK-PENCIL-HOLDER-BOGIE.stl | 588.3KB |