Cleanup pass for deep engraving acrylic

[essaynnc (Steve Tuch)]

Hey all,

I’m doing a deep engraving on 3/8" acrylic. 2 passes, but it leaves a plie of atomized debris in all of the corners of the letters, sometimes fused together so it doesn’t just dump out. We’ve done a few and scraped all of it out with a box knife, but…!!! I’ve done a standard clean-up line on all of the edges, but that isn’t enough to get rid of all of the debris.

Any bright ideas on how to do a 1/16" wide clean up “multi-pass” to clean up the corners?

thanks in advance…

[ednisley]

@essaynnc

deep engraving on 3/8" acrylic

Does using assist air help?

If the acrylic has protective paper / plastic film on the top side, then a vigorous air stream should blow the dust out of the trench as it forms, without wrecking the surface finish.

I did that for a batch of 0.3 mm deep (relatively shallow, by your standards) features on some acrylic signs and it removed essentially all the dust:

Can’t hurt, methinks!

[essaynnc (Steve Tuch)]

Hey, thanks for replying.

I’ve got the air assist on for this operation, and on this laser, I don’t see a valve or anything to turn the air up or down; it’s a constant flow. Perhaps it’s just too much “dust” to remove with the air assist??

The depth of the cuts total 1/32", the customer wants to inlay ADA acrylic cutouts into the resulting cavity. The dust piles up in the corners of the finished groove.

Any other ideas? Thanks in advance…

[ednisley]

@essaynnc

depth of the cuts total 1/32",

That’s maybe three times deeper than my signs and definitely has more “corner” for the dust to adhere onto.

My homebrew dual-flow assist air runs at 12 l/m, which is more of a stiff breeze than a jet blast.

Have you tried attacking the finished piece with a compressed-air blowgun and needle tip? If the dust isn’t sintered into a lump, a tight jet might encourage it to move elsewhere:

https://www.amazon.com/WYNNsky-Quiet-Flo-Xtreme-Flo-Extensions-Adaptor/dp/B078W1NVBY/

The needles surely don’t meet OSHA standards for compressed air tools, but, hey, it’s Amazon and you knew that going in.

[essaynnc (Steve Tuch)]

So i have had some success… I copied the outline onto itself, then added on offset .05" inside of that. I changed this second layer to a circular fill at a reduced power level and ran that after the initial engraving.

So far so good…