Best way to cut plexiglass

Lonewolf · Post by **Lonewolf** » Fri Apr 07, 2006 3:23 pm

What's the best way to cut plexiglass? I bought an 18x20 sheet last night, with a thickness of 1/8 inch, and I need to trim it to 14x16. This is plexiglass sheet, and not impact acrylic.

The edges don't have to be perfect because I have to mount it flush with a vertical edge, and am already expecting to have to do some filling of gaps.

I have a circular saw, Dremel, and razor knives at my disposal. I also have a hacksaw somewhere in the dusty innards of my shed. I thought about scoring it with a razor knife, and then "snapping" it the same way I cut styrene.

Thanks in advance for any help y'all might be able to give me!

Loachnut · Post by **Loachnut** » Fri Apr 07, 2006 9:47 pm

You should be able to use your circular saw. I would put a fine tooth plywood blade in though.

Jody

REL · Post by **REL** » Fri Apr 07, 2006 10:13 pm

A band saw or table saw is the best, scoring it and snapping it won't work though. But in a pinch the circular saw will work, and like Loachnut said use the finest blade you can find.

Try to cut it as fast as you can because it'll melt if you leave the blade in one spot too long.

DennisH · Post by **DennisH** » Fri Apr 07, 2006 10:53 pm

A hand-held circular saw??? Yikes.

Score deeply and snap that bad-boy.

Dennis

b5ranger99 · Post by **b5ranger99** » Fri Apr 07, 2006 11:22 pm

If it is a straight edge I vote with the score and snap method.
But score deeply and snap it over a sharp edge or place the score over a large dowel e.g. broom handle and press gently, work your way along the "break".

REL · Post by **REL** » Fri Apr 07, 2006 11:31 pm

D'oh! I just saw that it's a straight cut you're trying to do. Score and snap, forget the circular saw.

USSARCADIA · Post by **USSARCADIA** » Sat Apr 08, 2006 9:25 am

The circular saw can work, just turn the blade backwards. Not the best cut, but its fast and it shouldn't splinter. Make sure the cut area is supported.

Chacal · Post by **Chacal** » Sat Apr 08, 2006 1:36 pm

For plexi, the best scribe'n'pop technique is to scribe deep (it's 1/8", so go down at least 1/32" or better 3/64") on the "up" side (the one you'll bend AWAY) and shallower on the other side, so the crack you create will end on the right place (sometimes plexi will crack sideways on the scored line and will make a squiggly "bevel").

Post by **TER-OR** » Sun Apr 09, 2006 8:25 pm

If you can clamp the piece to your workbench with a wood slat you will find the snap method a lot easier. Just clamp it pretty close to the score line.

haywire · Post by **haywire** » Sun Apr 09, 2006 10:49 pm

I used the circular saw add on for my dremel. Worked great when making my rice fields for wargaming.

Lonewolf · Post by **Lonewolf** » Mon Apr 10, 2006 9:25 am

Thanks for all the replies!

I think I'm going to go with the snap method. I'll score it with a hobby knife first, then go back with a razor knife for a deeper cut. I'm going to be fitting this into a base, and I know I'll have a little trimming to do as I go. My plan is to score and cut one side first, check for fit, and then do the other side. As long as I'm within about 1/10 inch, I'll be ok. I already know I'll have a little filling to do around the edges, so I'm not really worried about that aspect of it.

Thanks again!

ModlrMike · Post by **ModlrMike** » Wed May 24, 2006 9:33 pm

I just watched a couple of guys cut a bunch of plexi into windows. They used an angle grinder with a cut off blade in it. I would suggest that a cut off blade in your dremel would work just as well.

Draw your line and then make several passes until you are through the material. You will have lots of debris, but you should have nice smooth edges because the blade will melt the plastic as it cuts.