Cutting plastic with Porter Cable Router

[mikea@mts.net]

Hello

Does anyone cut plastics with the porter cable router. We tried but the slowest spindle speed we can set it at is 13000 and it seemed to melt no matter what feed speeds we used. Any help would be appreciated.

Mike Annetts

[gerald_d]

Mike, if 13000 was too fast, then your bit diameter was too big.

[elcruisr]

Mike, what was your feed rate, depth of cut, bit diameter and type and lastly which type of plastic? All these will have an effect on your problem.

[rgbrown@itexas.net]

Mike,

I think all of the above is important. The FIRST thing to know is the material and it's properties. It actually is something that can be calculated and is predictable. Different types of plasic machine differently.

Ron

[gerald_d]

It may also be that Mike has gone too slow. Which seems to be just as bad as too fast for some plastics. . . . . .

[toys]

Mike I've cut acrylic with my PC with no melting
I used a two sided 1/4" bullnose cutter. There are bits that are specifically designed to cut plastics. They some have one cutting edge.
I think my PC is adjustable down to 10,000 RPM's. I know that I used the lowest setting when cutting it. My feed speed was 1 IPS and I only cut in .25 inch increments per pass.

If you go to http://www.woodworkerswholesale.com/
then go to cnc supplies and click on tooling then router bits and finally solid carbide you will find bits from 9 different manufactures. Some of which are specifically made for plastics.

Hope this helps.

[sheldon@dingwallguitars.com]

If you don't have a big job to do, you can babysit the bit with an air blow gun. In my experience - limited I admit - the most damaging heat comes from offal sticking to the bit and then rubbing against the stock. If you can keep air on the bit, you can blow most of that away.

I've got a vortex cold air gun on the way for other shop uses, but we'll try it on plastics as well. I'll post if the results are worth it.

[papadaveinwy]

Sheldon you will find the cold air gun invaluable for plastics, what was the price for the vortex (brand?) the one I use to use ran about $250.00 but that was 3 years ago.David in Wyoming

[sheldon@dingwallguitars.com]

Thanks David I picked mine up off of Ebay for $65.00. They usually go for about that much. How are they for air consumption? I've heard they can be hogs.

[joe crumley]

Sheldon & David,

I have had my Vortex tube for a few months and use it constantly. The air usage might be a concern. I have a 7hp vertical compressor with a 50 gallon tank which delivers 12cfm. It stays way ahead of the vortex tube.

The magnet on the side of the tube is handy. You can attach the unit on the Y Car frame. I keep saying I will make a better way of attachment.

Bit life is at least doubled on most stock. Aluminumn sheers as it should. This a great sleeper product.

I think I paid about $100.00

Joe

[pappy]

Steve,

Your answers lie at:

for information (http://www.arizonavortex.com/cooltool.htm)

[ssmith@skeeball.com]

Back to cutting plastic, I am trying to get a clean edge on ¼ and 3/8 polycarbonate. A ¼” straight bit left the edge looking like a hack saw blade. A ¼” up cut spiral would lift the ¼” sheet off the vac table (even when clamped on 2 corners). I tried both ends of the porter cable speed control and my move speed was 0.7”/sec.

Any advice? Faster, slower, bit selection, quit my day job?

[elcruisr]

We've cut polycarbonate up to 1/2". The secret is to use an O flute tool in solid carbide designed for soft plastics. Keep your RPMs at the lowest and try a 1" to 1.3" per second feed rate. For those thicknesses you could use a straight flute tool and it wouldn't hurt to use compressed air to clear the chips. If you still have trouble try the cut in two passes. A normal router bit will make a mess. Try Onsrud Cutter or Courmatt International. We've had very good results with plastics tooling from both sources.

[mikea@mts.net]

Thanbks for all the replys. We were cutting "puckboard"I'm not sure of the exact name. It is used to line the boards of hockey rinks. Fairly flexible stuff. we also have some polyeteline (I beleive-it was donated to the school) that we would lkie to cut. I was usingan 1/8 straight cutter at varying speeds form .5 to 1.5 with different rpms. We tried water cooloing and air wiht no result. I will follow the links for the speciality bits.

thanks again

Mike

[gerald_d]

Mike, ignore my "bit is too big" remark right at the beginning. When you mentioned porter cable, I thought that you were trying to indicate a 1/2" shank bit.

A 1/8" straight bit probably can't cut deeper than 1/8" without causing problems . . . . .

[elcruisr]

Mike, I forgot to mention that I use a 1/4" cutter on stock up to 1/4" thickness, after that I use a 3/8" cutter, much less deflection. I did some 1 1/4" acrylic with a 1/2" bit one time. If you need you can sand the edges even smoother with 150 or finer sandpaper.

[sales@courmatt.com]

Use a 1/4 slow helix up shear. This will assist in removing the chips, but not lift the material. As for the melting @ 13K rpm's you are running your feed speed to slow. A cold air gun will create a big differance as it produces about 100 degree lower than the air it takes in. Also the tool will last longer. We mfg a variety of sizes and angles just for plastics ( also for wood )

[gerald_d]

Greg sounds like a pro - his e-mail address puts him at www.courmatt.com (http://www.courmatt.com/).