Cutting Acrylic Recommendations

I have the Dewalt 611 and I am going to be using a 1mm, 2 flute, upcut bit. I will be going through 3mm acrylic sheet.

When setting up easel, it wants to do one pass (which doesn’t seem right for a small bit). MY questions are:

Would it be smart to do 2 passes to cut through the acrylic?
What is a recommended spindle speed for cutting acrylic?

Thanks, and any help is appreciated.

@WilliamRoberts I’m seeing a default depth per pass of 0.02" (or ~0.5mm) in Easel for that bit size with acrylic? I definitely wouldn’t go deeper than that with a small bit and a brittle material.

If you run a test and the chips are melting back into the cut path, your spindle speed is probably set too fast. If your bit breaks, the speed may be too slow. I’m not sure about a speed to start with.

Do you have to use such a small bit. I find with acrylic use the largest bit you can get away with. Single flute is better as well. But to answer your question. I would do 3 maybe even though you probably could get away with 2 (just feels safer). When cutting acrylic heat is the enemy to a good finish so sharp bit, slow rpm, fast feed. I cant give you specific numbers (I don’t own a dewalt) but with 2 flutes slower rpms than you think. If you can do test cuts do it.[quote=“AlexBerger, post:2, topic:33047”]
'm seeing a default depth per pass of 0.02" (or ~0.5mm) in Easel for that bit size with acrylic? I definitely wouldn’t go deeper than that with a small bit and a brittle material.
[/quote]
6 passes to get through 3mm seems painfully slow, just my opinion.

Or you bit is dull otherwise 100% Agree.

Thanks. So, is there a way to set up a break in the middle of the cutting to change out the bits? There is some very fine detail work I need to plunge through and then I can use a larger bit to cut the outlines.

I’m assuming that I just make a copy of the easel project and then delete the outlines from the first carve project and delete the detail work from the second… then when the first one is done, just use the previous home location and restart the cut after I change the bit?

Are you using Easel? If so there is a way to do a tool change it is still a beta feature. To enable it you have to go to machine click the advanced in the bottom right corner and then enable two stage carving. I have not used it yet. I’m guessing that you will be prompted to change bits and reset your Z. I’m sure if you search this forum you can find more details on two stage carving. If not what you were proposing (sending as 2 separate jobs) should work. Just don’t loose your work position. Also you can cut acrylic successfully with a 3mm end mill I would however suggest it be single O flute. Lager mills just cut better. It all has to do with chip load and removing/ not generating heat.