I started with the little Chinese cutter as recommended and sold by Ryan, and found it fine for vinyl. I’ve made some nice decals with that. I’ve found fairly sharp corners no problem with no corner actions on that because the blade and offset are so small. But I haven’t done much lettering where it would show up more.
Having played with cardboard cutting on a laser, I’ve turned my attention to cutting out bigger shapes in cardboard with the MPCNC. Hence I made one of these:
But put an additional spring in the assembly. Using that I can cut 7mm cardboard in several passes, but it fails occasionally (blade sideways, emergency stop!), so I’ve been thinking about building variable offset into the design. Donek’s tools come with different offsets for different depth and cut radius specs. Only trying to cut circles at the moment, but would use the Donek spreadsheet to do corner actions if needed.
Funny that you showed up dkj4linux, I came to the conclusion on the train this morning that the answer for thick cardboard was to build your needle cutter! I was always destined to do that, but this has given me the push.