hi there, don't know if this is of interest to anyone, but here's something I've been toying with. Using 0.1mm (0.2 in vid) peck drilling seems to improve the release and reduces plunge depth. That's pvc in the vid, but could be adapted for card, leather, gasket, rubber etc. Coupled with drag knife, opens up a new world of materials Next I'm going to machine a fitting to go around the punch with a spring and foot to hold down the material on retract.
Something mesmerizing about it I could watch this for hours That is a really neat idea @Jonny Norris! I have never seen this done before thank you for sharing it.
It really does need a spring loaded foot though, had a couple of accidents around the edges where it picks up the material and turns it back on itself as it moves to the next hole. Having to hold it down by hand atm just have to keep eyes glued to it and keep track of the toolpath so as to avoid it punching a hole in your hand, not ideal but a foot would solve this.
Tried it initially you have to go deeper to get the release, with the mdf bed which compresses a fair amount as you can see. And going deeper sends the material further up the punch so is more likely to get stuck on it and get lifted on the retract. with a punch and hammer you generally have a iron block underneath. To do it as you would with a hammer you'd have to do the same and use a metal plate underneath. Repeatedly plunging within microns of it, and i don't think you would get the realease unless you actually hit it. Personally I think you'd be nuts to try it. I'll Stick with a soft bed, it takes a little longer but it won't shag your bearings and ball nut half as quick. But most of all it aids the release, suppose it wears the hole slightly larger during the peck so it comes off easier. Pvc is soft but still takes a fair force to go through it with a punch, as you say a hammer usually so pretty much answered your own question lol Possibly with a spring loaded foot to hold the material down as mentioned you may have a chance at going through in one and it coming off, think you'd still need to go a bit deeper with a ply bed tho Took a fair few attempts at it to work out I needed to peck drill, before it was randomly picking the sheet up dragging it over on itself as it tore it. Wasn't pretty.
wonder if there would be a market for a punch with a spring loaded foot mechanism, not even sure what they are called lol possibly with interchangeable heads for different size holes
to get easy release you need to polish the punch, I think. and maybe make it thinner so it is not expanding the material a much = less grip. but looking good. what CAM are you using to generate your Gcode?
Yeah I have had a go at that, but found if you make them too sharp the edge can round over after a while. And most of these things are never straight enough to turn, which makes it difficult. Vcarve in the vid, also use inventor Hsm 2016
