Straight away I didn’t have any proof grade materials to run with, but I did have a bunch of cardboard around. The thin cardboard is from soda water… it’s like a note card, maybe this is referred to as card stock? The thicker cardboard is “Amazon” cardboard… whatever they ship with.
To play with power settings I started at full speed, then ramped up power in increments of 10. For the Amazon cardboard it was obviously not going to cut so I started jumping up in power increments of 100. But 100 and 500 speed wasn’t doing clean cuts so I jumped up to Full power and 500 speed. That cut! But seemed like it might be over kill and cause fires, so I went back to 100 power and started dialing down the speed settings until it cut through at 465 speed.
Please do chime in if you’ve got a better approach to exploring settings for NPGM. I saw this clever project for a compact block to test power settings but I’m not sure how to achieve similar on GF. Load up a series of art and manually set power settings I guess?
And finally I grabbed a clamp off thingiverse and gave it a go in cardboard… kind of worked, but the cardboard destroys itself even without a significant force from the bands. Maybe I’ll try make it two layers of cardboard deep for each part instead of one… or maybe I’ll try some real material
As I can attest, you have to watch your paper products closely. It’s not a question of power setting, but how much energy is being delivered. So a lot of power combined with a high speed may deliver less energy than a slow speed and less power. As you can see from the comments there is no one true setting. For 0.25" corrugated cardboard I use 90 power and 210 speed if I want a clean edge that I have to punch out and 90 power 180 speed for a sooty edge that falls out.
I believe @jamesdhatch left one or more of his test grids in the Free Laser Design section. I’ve found it doesn’t take long to get close on cuts with a little interpolation. If you want the perfectly browned edge then it takes time. As regards the perfect engrave settings, I think it is as much art as science.
Incidentally, as someone who’s also waiting for his PG shipment, another good source of cardboard is USPS “priority mail” boxes. They’re thin, and quite strongly corrugated, so the resulting cuts hold their shape pretty well. I’ve had good luck at 180/60 with them.
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