I am cutting out a bunch of circles and honestly tearing all the tape off them hurts my fingers. How necessary is the tape for just cutting acrylic? I don’t imagine there is really scorching on it.
I tend to leave the tape on the bottom due to flashback concerns, but the top layer is definitely optional. (That cuts it in half anyway.) 
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I’ll take half. I have about 240 circles per sheet, and 4 sheets. Thanks!
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Duct tape can help here. Acrylic sticks to masking pretty hard though, so maybe not. PG? PG masking is a bit too well-adhered if you ask me.
As for the “bottom only” method, yeah that can work but you should test it to be sure you don’t get any residue and hazing around your cuts on the top surface – it can be impossible [well, difficult] to remove. You usually only see it in engraving but it’s worth a test.
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I’ve been doing a lot of acrylic. It really depends on the type of acrylic and what you’re doing. For example:
PG Acrylic: Scores and Cuts? You can take the tape off the top. I’d leave it on the back to prevent scratching and flashback from the crumbtray. But if you’re engraving – especially thick engraves – then it will throw up a lot of fine dust. This hot dust will land back on the acrylic, making it as bad as being scratched. If you leave the top tape on, then the dust just gathers on the tap or along the front-edge (front of GF) of each cut. Then you can just scratch it off with a thumbnail and polish it with an old toothbrush.
Non-PG acrylics really vary by vendor. Some leave an oily residue or warp around cut/score edges. Leave the tape on to reduce these issues.
My general rules for my uses:
If it’s PG acrylic and it’s just cut or score, then you can remove the top tape. For engrave, leave it on.
For non-PG: If the acrylic has paper tape, leave it on. This will reduce warping at the edges.
If the acrylic has plastic, then remove the plastic and replace it with painter’s tape (blue or yellow tape). Expect an oily substance after cut/score/engrave; wipe it off with a tissue.
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One more thought about cut-only on PG: You can always remove ALL tape (front and back) and put the acrylic on thin cardboard. (I’ve been breaking down cereal boxes because you can never have too much thin cardboard.) The cardboard prevents the scratching and blocks the flashback.
Be sure to use magnets to hold the acrylic onto the cardboard onto the crumbtray. (I use magnets stripped from old hard drives.)
Your mileage will vary! Test first before going full production mode.
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I think I’m going to take the tape off both sides and do your cardboard suggestion. I’m using PG acrylic.
I’ve successfully used aluminum foil to prevent flashback. That doesn’t introduce the extra flammability element of adding layers of flammable material with air space in between to encourage flames. 
Gorilla tape is my go-to for getting the masking off acrylic. When I was making the bazillion little pieces for my [Mastermind](http://Mastermind Game With Rack & Pinion Box Latching Mechanism) and Catan games, I’d lay out a strip of Gorilla tape, stick a bunch of masked cutouts onto it, give them a minute to adhere, and then peel them back off and do the other side. Still tedious, but you don’t risk the hazing you might see otherwise.
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My experience is that without the masking the atomized (is that the right word?) acrylic causes clouding opposite the fan that requires polishing to remove.
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I’m not overly worried about the circles being perfect, they will be stacked together so a lot will be hidden. What if I put a piece of my own masking tape (very much like the tape GF uses) on the crumb tray (sticky side down)? That would potentially stop flashback and it would be any spacing at all.
Correct, but is most likely to be seen when engraving. When just doing cuts, and presumably not a lot of very intricate ones, you may not see the clouding at all.
Since it’s just cuts it shouldn’t an issue then. Here’s what I am cutting out. I’ll even see about carefully removing the tape from the sheets and just using those upside down so I don’t waste my own tape.
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There’s no one correct answer, although “in general” acrylic does not mark like wood, so you can get away without masking more often than not. For your own work, you need to test and see what works best for you.
I personally remove masking on both sides for detailed designs, and have not encountered a situation where this caused any issue.
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For assisting removing tape, mainly “weeding”, I like using simple wood clothes pins. The wood is soft enough it doesn’t leave scratches on most acrylics* and tough enough to remove masking.
But it’s not always the best at starting at the edge to get a big area off–but sometimes it works, or some tweezers or other firm edged item (screwdriver) to start lifting up the masking when my thumbnail gets too short to do so!
- Haven’t had issue on PG, but have one one of the many non PG versions I bought that did scratch–all cast. So 90% so far no scratching from clothespin to get off all the masking post-etching).
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I won’t recommend sticking anything to the crumbtray directly. The first laser pass will cut it and might burn it onto the crumbtray. After a few uses, it will be hard to remove and possibly become a fire hazard.
@geek2nurse I’m going to try that aluminum foil trick for acrylic flash back reduction! Thanks for the idea!
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Is flashback caused by the honeycomb or the silver insides of the tray?
The edge of the honeycomb in contact with the material. Anything more than a mm or so is not going to have any effect.
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Another consideration would be to leave a small tab, score it and then break it to start the tape peeling.