Need Advice: Routing Plexiglass

[animuL]

I have a customer wanting me to route out some 1/2" thick pieces of plexiglass. I am using a Thermwood CNC router. I am wondering what kind of spindle speeds, feed rates, and cut depths to use. Also would a standard straight cut, carbide tipped, 2 flute router bit do the job? My main concerns are chipping out (which is why I think a straight cut or maybe a down sheapering is best) and then I wonder about melting it which is why I ask about spindle speed and feed rates. Any help is greatly appriciated!

[neilw20]

Quite low spindle speeds, I think, so you don't melt the material.
Try out on some scraps. You will know if spindle is too fast.
Plastic will melt into the cutter flutes and clog up things.
Make sure test pass not too deep, as you may start pushing a solid non cutting cutter as a plough.
Keep PLENTY of air so no swarf gets eaten by the leading edge of the cut.
You can push fairly amazing feed rates once you get it right.

[svenakela]

If you have enough air, let it flow a lot to cool the tool and the piece down. As Neil says, keep it at a low RPM.

[txcowdog]

I run at 2500rpm and 20ipm with a 1/4" 2 flute.

[skottc]

It's actually the opposite. Very high spindle speeds and feeds. 18,000 rpms and a feed rate of > 100 ipm. Maybe take two depth cuts on 1/2".
Orange County Industrial Plastics

[ger21]

Get a tool made for plastics, maybe something like these.
http://www.vortextool.com/index.cfm?...category_id=52

Depending on the part, cut it in one or two passes, then make a cleanup pass of about .030. Depends on the part, but you should be able to make the rough passes at 150-200ipm. Maybe a little slower on the cleanup pass, depends on finish quality your getting.

[skottc]

Gerry - I couldn't have said it better!

[easyprototype]

Originally Posted by animuL I have a customer wanting me to route out some 1/2" thick pieces of plexiglass. I am using a Thermwood CNC router. I am wondering what kind of spindle speeds, feed rates, and cut depths to use. Also would a standard straight cut, carbide tipped, 2 flute router bit do the job? My main concerns are chipping out (which is why I think a straight cut or maybe a down sheapering is best) and then I wonder about melting it which is why I ask about spindle speed and feed rates. Any help is greatly appriciated!

Where I work we use a Charly4U CNC. In the software, the setup for plexiglas using a standard 1/4" 2 flute router bit is

9500 RPM
Feedrate: 8 mm/s (19 IPM)
Depth of cut: 2mm (5/64")

For a 1/8" 2 flute router
9500 RPM
Feedrate: 20 mm/s (47 IPM)
Depth of cut: 1.5mm (around 1/16")

The tool is not air-cooled or anything. I have no problem cutting plexiglas with these speeds but it might be a little slow for a commercial purpose...

[R.Peters]

hey i have a biesse rover and im getting ready to cut 1/4" plexi using a 3 flute 1/2" compression cutter do you guys have suggestions on spindle and work speeds for me???? thanks