And create a calibration file of boxes at various power and speed combos - you’ll want one for cutting & one for engraving. Run it for new materials or new suppliers. Definitely run it on a scrap of the material you’re making a critical project out of as even from the same supplier the same material may behave differently.
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Yes, it seems that with one well-designed test you can see the effects of speed vs power on any material over a wide range of possible settings.
Remember when testing material (on any laser) that the speed listed for vector movements is a maximum only - the motion planner will always slow it down for corners, turns, etc. You need a fairly large test area to ensure that you reach peak speed.
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Ah, thanks. I obviously don’t appreciate the nuances of testing all the variables involved.
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It’s a nuanced pain in the tuchas. 
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Well that turned out great! I don’t have a 3D printer, but I sure would like to try making a baby griot bust out of cardboard using the slicing method. Might even clay or bondo over it.
I like the griot measure test. Worked perfectly!
So does the laser power reduce where it slows down to compensate?
From what people have said elsewhere is seems you need to keep the speed up to reduce charring and that gives the impression you can’t always compensate with power reduction. And I presume there is a minimum power before the tube stops lasing. So does that mean sharp corners are always over cut?
When I design objects for 3D printing I always try to round the corners to get nicer results as the corner can be taken at constant velocity and hence constant flow rate. I don’t have one axis slower than the other though.
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Now, yes. We have a variety of improvements in the hopper.
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what is max engrave speed going to be?
Nothing to share there yet, but it’s still something we’re working on.
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I don’t notice this issue in the cuts. It’s the scoring where it literally comes through at the corners. Instead of a nice even line around tight corners, there is a deeper indent. You can see an artifact of this in the Corian engraving which also was a score. I’m figuring out ways around it, but I’m amazed at what 1% power can do on a piece of 2 oz leather.
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I believe @dan said that would not happen because the goal behind proofgrade and the barcodes was to have a material that had been tested and verified to work exactly as the machine interprets it – using the same settings automatically on another similar material but with potential variations might have very problematic results.
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Starting to think that the amount of energy at the chosen material will have a minimum threshold higher that I had hoped. In other words the power/speed combination will mean at least one of my planned projects might be impossible. The laser will always burn through delicate material rather than char. Scoring paper could also be a problem. This of course was never promised, though there was a lot of hopeful speculation. Either way will enjoy the GF and have plenty of other projects ready. Just expecting one of my ideas will end up in the round bin. Won’t know until they are done tweaking and I get my hands on a unit.
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Paper as in cardstock (100lb) or paper as in printing/typing paper (20lb)?
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Not sure you’re required to use the Proofgrade settings even if you’re using Proofgrade materials. If it’s true, that would allow you to tweak the settings even for Proofgrade so you can cut power levels if you need to. @marmak3261 can confirm that. Right now the easy approach would be to hide the barcode so the machine doesn’t see it even if it’s automatically applied.
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Ive been wrestling a bit with this issue lately. A number of things ive been trying to engrave have either been burning or just obliterating completely on the lower power and highest speed. (paper, cork, foam, cedar)
e.g.
Keep in mind these are raster engraves. I havent been trying vector scores, but this fix could apply to that as well. I have found a hacky way to get a little better results for these sensitive materials. my images have all been grayscale images with black (0,0,0) being the darkest color. If you take one of these files and scale the output levels to make the lowest output level/color a lighter shade of grey like 50% (128,128,128) grey and up, it will effectively still reduce laser output power even if power is set at 1%.
so the image above ended up looking like this after scaling the darkest shade in the file to 50%:
Im assuming you can continue doing this up pretty far to maybe even get close to 1% of 1% of power, but I havent tested that far. Laser tubes have a minimum power necessary to activate, so it might cut off at a higher point unless they accounted for this in the software already. Ive got some other materials I want to test on (paper, EVA foam) and can post results when I get them.
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That’s certainly an issue. I like your workaround though. Might be the ultimate solution. 0,0,0 will certainly try and be the darkest/deepest burn. Adjusting the curve seems a fairly simple answer. I hope somebody else can provide a better one though! 
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The original website did promise the ability to both engrave and cut paper, so this is something that should be delivered. I remember @dan saying something about how the motors are capable of moving the head a lot faster than the motion planning software is currently allowing it to move. I also seem to remember something about them still tweaking the power levels that the percentages entered produce. Perhaps at this point the problem as much about the artificially slow head speed as it is about the minimum power output for these delicate materials?
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For the ultra delicate materials, if you are still too high of power at lowest power and highest speed, the next move is more masking.
As for paper, my 60W is able to make lovely scores and engraves (no char in either case) on 67lb Cover Stock paper. I run 8000mm/min and 60% power to cut, 40% power to score.
So, as long as @dan and company can give us 8000mm/min speed, a 40W can absolutely accomplish what 60% of a 60W does.
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This is exactly it. Speed will mitigate power. As long as it can handle the power switching necessary to keep up with the speed this will fix power being too high. It seems there is quite a bit of room to increase engrave speed so that more sensitive materials can be worked with.
In the meantime, if it’s an engrave(maybe scores too!), @marmak, you might be able to just lighten the file to get it shallower
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