I just finished my first LED sign. It is okay but I see room for improvement. Your suggestions are greatly appreciated. Here are the details for the technique I used -
Bit - 1/16", 2 flute, square end http://www.ebay.com/itm/381588491263
Feed Rate - 75 in/min
Depth per pass - .01
Total depth - .025
I had a fan blowing across the project. I didn’t see any melting.
Problem -
Up close, you can see the swirls very clearly. From a small distance, it looks okay.
Finished project mounted in a piece of an old fence post -
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Very nice work, looks great.
Looks great. I especially like the way you integrated the fence post.
I too get the swirly marks too on occasion. I’ll be interested in what others say about it.
@TysonSwan I’ve done very little acrylic carving and I’ve never done an edge lit sign at all. Do you know how this would go using a V bit to do the carving? I do lots of v carved stuff (and I love the details I can get) and thought it may be possible to combine the two.
I’m not sure how it would work with a v-bit. I had the same thought though.
The biggest issue I have seen with carving acrylic is melting. You must turn the RPM of the spindle way down and move the spindle very quickly.
The cuts into the acrylic are very shallow. If you have a design with wide carves, the v-bit may go too deep. My piece of acrylic was only 1/4" thick.
If decide to give it a shot, please post your results.
I use regular ballnose bits for my acrylic signs for wide spans. Then various vbits or etching bits if I need any line detail. I find there is just enough resistance from the acrylic that your speeds give me rough detail too. I run mine at a max depth of cut of .01…and usually only go .015 to .02 deep. I use a feed rate of 40-45 in/min max. For the sign part I let the dust shoe keep up with it…for the profile cuts I use a “O” style bit to cut out and will often follow it with the shop vac by hand just to keep it clear. Once done I use a plastic bristle brush (basically like a toothbrush) and run over all of the carving with that to break out any of the acrylic that stuck into the fine crevices or details.
I did a 12x24 with 60 degree V bit this weekend and it turned out great.
Looks great. Nice job. 
if you want an extra step that will give you nice frosted look then use a diamond bit to go over it
I have experimented with them and they work great at low speeds and feed rates. Also use air or other means to prevent the tip from getting melted plastic on it. Dremel makes some small ball end ones for larger areas and you can use the pointed ones like vbits.
