These little jigs and the holder are meant for trimming leather lace, particularly when plaiting like for a bullwhip. Sizes are in mm, your sharp blade goes in the notch, and you can just pull them the length of the lace you want trimmed.
The holder is meant to have 2, 8mmX3mm magnets, available on amazon.
If any more sizes are needed just ask, they are super easy to add.
I recommend printing the pegs in high resolution, the smoother they are the easier they'll be to use. Also I like 4 exterior layers to stiffen them up along the length. Of course plastic with shrinkage isn't a great idea.
If you need a set printed drop me a line and we'll work something out, probably in pet-G so there isn't a chance of warp in shipping in a bit truck, although harder pla is a bit nice. Polycarb soon I hope.
**2019-03-01 Several requested sizes added, there are 30 pegs now. Don't expect more of your printer than it can do. Not every printer can do the resolution needed by some of these. I also added a 15 peg holder, and you just print 2 of them if you want them all.