Best setting for kiss cutting/mask cutting of paper on acrylic

[DSweet (Debbie Sweet)]

Hello Jack

I do a lot of mask cutting/kiss cutting of the protective paper on acrylic. My couple attempts haven’t been as nice as my old laser. Either I was too deep into the acrylic or too light and when I peeled the glue wasn’t severed enough and would pull and snap back making little “balls” that I had to rub off so it wouldn’t make a messy edge for spray paint. Also It did a weird thing of repeating the line but was a hair off and a double line. I want a nice fine razor cut through the paper (and glue) and a slight hairline into the acrylic under the paper.

Can you please suggest settings and process in Light burn? Thank you very much

Debbie

[Blake (Blake Bartlett)]

Settings are going to vary from laser to laser. Everything else the same, they’re still going to vary by geographic location, today’s weather report, or how many farts you’ve let off in that laser room. Heck, I wouldn’t be surprised if you got different outcomes with everything the same, just a different dispersion of adhesive on the paper backing.

Are you saying you’re unable to go around twice, because the laser isn’t on the same exact line? I’d get that problem solved first, if that’s the case.

Are you changing speeds and powers by very small amounts? Do you have air assist?

[jkwilborn (Jack Wilborn)]

@Blake is probably pretty close even without the methane gas being involved… it is explosive…

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I have done something similar. You have it rather close if you are just getting some ‘stringy’ edge residue but it’s peeling off.

I load a ‘line’, usually the width of the material. Cut the material if necessary to lower the cost (multiple tests) and make it easier to manipulate the material for observation.

If I wish to engrave deep enough for magnets, I can run higher or lower power/speed set at the console and figure out what power/speed gives me the proper depth. I only need a line to see how deep it goes.

I think you are probably close to the ‘sweet spot’. What I mean is all machines vary the ‘speeds and feeds’ for the best results. It’s most obvious in a milling machine or other tool. Move too fast it ‘binds’ the tool, too slow it over heats the tool.

If you run 100mm/s at 50%, it should be the same amount of ‘heat’ as 200mm/s at 100%. If it cuts at 100mm/s @ 50% and it cuts at 150mm/s @ 60% there is some spot in the middle where the speed and the power result in the best cut, least amount of ‘burn’ and a more ‘clean’ cut.

I’ve had some mdf that cuts at 60% power, but at 68% power it cuts so clean it leaves no carbon residue. Wipe you finger over it and your finger is still clean…

You will probably have to fine tune either the speed, feed or both for best results. Laser power is usually associate with the ‘speed’ and feed is the how fast the material or head move past each other.

At that point, you need to load a square or something that has corners to figure out the best minimum speed. I assume a vector cut.

This is so important that I pay real money every year for a windows program that runs on the wifes computer so I can compute only speeds and feeds for a particular bit/material. Haven’t figure out how to do that with a laser beam… I think there are too many variables…

I wish I could give you a pair of numbers and you’d be a happy camper for life…

You will notice how quick and easy this can be after you’ve done it 3k times… it’s a learned ‘art’ …

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As far as it not following the line exactly, that is a different issue. They both need to be fixed but it’s unlikely that one cause is responsible for both. I’d look at them as separate issues.

Good luck