Cutting Lexan Sheet

[Bill D]

My local hardware store has 2x4x.125 Lexan sheet. I would like to cut a piece to make a nice looking battery cover. Can I use my table saw with a 100-tooth narrow kerf blade to cut this? I would sandwich the Lexan between two pieces of 1/2" particle board so as to not scratch the surface. But I want to know if the saw blade is going to cause the sheet to splinter.

Thanks
Bill D

 

[Lynn Larsen]

Bill,

The sandwich might do it, but what ever you decide, I would highly recommend a test cut on scrap (or what will end up as scrap) to make sure.

Lynn

 

[Jonathan Strain]

You also may want to try as low a speed as you can on the saw. My experience is the friction on the blade on most power tools melts the lexan as it cuts.

 

[Bill Musarra]

Melting is not a bad thing. It will give you as smooth an edge if not beter than, a slow cut. It also will keep it from "biting" and causing a crack. Just don't push it too fast into the blade. This might leave a little residue on the bottom side of the cut, but is easily removed with a knife edge pulled away fron the sharp edge(does that make sense?). If you have ever worked with PVC, its the same thing. Most of their cutters are wires that melt the plastic. We use the same thing in the O R to cut certain big bones, but that's another story!!!

Bill

 

[Bill D]

Thanks guys. I'll let you all now how it goes this weekend

 

[fostereast]

You may also try routing it if you have a router with a variable speed control on your router. I bought a speed control for my router and I suspect I could find a good speed range to make a good edge once I roughed it in with a bandsaw or jig saw.

 

[Bill D]

FosterEast-
That's a brilliant idea. Thanks

 

[Lynn Larsen]

Bill,

If you go this route, the direction with respect to the spin of the cutter will make a difference. One way the plastic buggers (this is Mark Clapp's term) will build up on the finished work, the other direction and the buggers will build up on the scrap. Its been so long since I did my light covers that I got from Mark, I can't remember which is which. Again, try a piece of scrap and you'll quickly find out.

Lynn

 

[Paul Butvila]

Here is the skinny on lexan. I have been working with this material ( it is actually polycarbonate ) Lexan is the trade name. for about 30 years. Cutting small "test pieces " can result in you wearing the off cut, be carefull when doing that. I use an 80 tooth carbide blade on my table saw, hold onto the piece while pushing it through the saw, it will want to kick back quite violently if you do not have a good hold on it, and by all means make sure you push it through all the way. Do not try to cut it half way and then pull it back towards you, it will get you right in the jewels if you are at the right height. It is much harder to cut than acrylic. Routing lexan is a whole other ball game.

 

[Mark Clapp]

Bill, as Lynn said if you cut with a router around the piece counter-clockwise the heat-buggers (technical term, not to be used by novices) will be on the scrap side and the piece will stay clean. The nipping action of the router is a better way to cut than saws for plexiglass. Keep the cling-wrap protective sheet on the lexan, it is very soft and scratches easily. You may consider getting the hard-coated lexan, which I've seen called MR-10. Ask the plastic supplier and they will know.

 

[Bill D]

Thanks Mark

 

[Dan S.]

Hi Bill,
the only other way to cut whould be to score and break. since you are only 1/8" thick this method might work for you.

 

[Phil]

Bill
If the shapes are square or straight sided I simply shear it, never had a problem unless it was really cold. Also if you care to get creative it bends quite readily in a brake, and it may take a little more overbend than a sheet of metal it generally will hold its shape.
Cheers
Phil

 

[Howard Jones]

Bill, Did you know that Tap Plastics will cut Lexan to size for you for very little money.

I had them do my small rear window in the bulkhead. It was something like 35 dollars. I just took in the cracked glass one and told them to duplicate it for me in Lexan.

Their mistakes don't cost you anything. They might even cut your material for you for a slight fee.

 

[Bill D]

Good idea HJ. I'll check it out. I'm tired of making stuff 2-3 times to get one useful part.

BD

 

[Mike Christian]

I have used a die ginder with a cut off tool for the rough cut and then use a palm sander with 150 grit to finish of the edges to the final line. The cut off wheel melts the plastic as it cuts for a nice smooth cut. Thewheet I have is pretty thin.

I used this technique on my aircraft canopy and made several cuts to get to the finished size.

Regards,
Mike