1/2" Acrylic suggestions

[r_jones]

I have a project coming up where I need to cut 1/2" acrylic in one pass with a bullnose bit and was curious if anyone had any recommedations? i am cutting with a PRS Alpha and 3hp PC. I do have a spindle on order but I don't think it will be here in time

[bleeth]

Ron: The secret to cutting 1/2" Acrylic in one pass is DON"T unless you are not cutting too deep.
Are you planning on cutting through? Then the bullnose is the wrong bit.
Assuming you are not cutting through, how deep do you need to go? What type of Acrylic? Corian, Cast, Extruded?
What diameter bullnose? Is this a relief carving?
Either post or send me more info and I'll try to help.

[bruce_taylor]

The bullnose can be difficult to cut because any deflection or uneveness in the table shows up in the cut. It cuts down deeper than the spoilboard unless you hang it over the edge to cut it.
I cut corian built up to 1 1/2 with a bullnose with acceptable results. Starting about 200 feet of edge in the next couple of days.
very important to keep it flat, very flat, very very flat. A old fashioned router table can work well for edging straight runs,
I use one for 1/8 overs on splashes and such . Normally while the bot is cutting other things.

[r_jones]

Thanks guys! I think what I may do based on your suggestions is rough cut planks maybe 1/8" over, set up a fixture maybe a 1/4" off the spoilboard, load the planks one by one and then one pass to take the 1/8" off and finish. Maybe I can then run the final pass at 5ips maybe 12,000 rpm?

[bruce_taylor]

I normally cut 1-2 ips on my alpha and make a couple passes offset .2 then .1 . Make sure you tool path so the bit clears the cut before it ends and moves up. AIR CUT FIRST!!! The tool pathing is very critical it has to come in from the side so modifying the cut file is mandatory. If you have alot to do you can set up a couple jigs so you can switch pieces while the bot cuts the other side. Hope this helps. I have almost no sanding when done right.

[r_jones]

Bruce,
I love the idea of doing a couple jigs! Thanks again for the input!

[bruce_taylor]

I got the idea from Gary Campbell on his dove tail routine. The people on this forum are some of the best in the world. Glad I could share some knowledge as others have been so giving to me.
Bot on

Bruce