Hello, so I am trying to print a console for a Batmobile. With it I’m printing on 1/16 acrylic. It is mostly cutting out the items but there was a few parts that were engraving. The machine warned me that it might melt/start a fire because of how small the area is. It did end up melting the acrylic in the spots it was meant to engrave. Any thoughts/ideas on what could be done to correct this?
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Without seeing the file is a bit of a guessing game… So I’d guess you want to lower the power of those engraves. If cuts are causing problems, they will need to be simplified.
Overly complex motions in a tiny area force the laser to remain in one place for too long, building heat levels very quickly.
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Yeah there’s a lot of smaller things grouped near each other so I’m thinking maybe of cleaning up the design and simplifying it.
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Yep, that’s sounds like a good plan.
Acrylic fires are far too common, keep a close eye on it!
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If you have the ability, try cutting the area with the small pieces into several overlapping groups, then rearrange the settings tiles to provide some distance between each operation. Alternatively, you can pause the engraving at random intervals to allow the engraved sections to cool off before starting again. And one final way to limit heat buildup, run the engraving sequence at a really low power setting, but run it several times, stopping when you achieve the effect you want.
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I might be wrong, but I thought the material warning for this stuff only popped up with Proofgrade materials. Are you selecting a Proofgrade material? If so, are you using the default settings or are you modifying them for the thinner acrylic?
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Acrylic retains a lot of heat. Often “regular” acrylic (medium proofgrade) parts are hot to touch immediately after a job completes.
Thinner acrylic doesn’t have the mass to dissipate that heat, so for starters it sounds like you’re using settings close to those for proofgrade.
You need to find settings that work for your material by testing. You’ll likely end up with lower power settings and slower speeds. I’ve used quite a bit of ~1.8mm acrylic and for large engravings, I can run full power (Pro), but each pass takes several seconds so the material has time to cool. For smaller engraves I have to slow it down and reduce power or it gets all melty. For cuts, the same thing - for dozens of jar lid labels it was OK to use full power at a high speed because they are spaced out. For small items, close together, or with internal details (think earring-like objects) you have to use lower power and slower speed. I’ve also broken out multiple internal cut paths (different colors in design) so it can cut one part, go somewhere else for a while that area cools down, then come back.
All of this is just a way of saying, you need to adjust your settings, and possibly design layout, to give the material time to cool down between passes (engraving) or adjacent areas (cutting).
If we had a pic of your design (with something for scale) perhaps we could give some more specific advice. I have made some incredibly small parts from acrylic, that I had to assemble with tweezers.
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I had it selected as a proofgrade material but was using custom settings. Though I also had it on autofocus so with l the replies I’ll give some a whirl.
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