90 ton 1/14 metal excavator scratch build w/embedded PC

[crusher]

As I have written before your build is great , ton of info for us beginners, can I ask a couple of questions, what DP or MOD did you base your swing gears on, I am trying to cut a pair but cannot seem to come up with a workable combination,( do not have cnc) I am also very interested in 3D printer work, about how long does it take to produce your track pads and if I may ask what make of printer do you use? Thanks for any info you may have.
Terry