Help cutting plexiglass

[Brianr24]

I have a project I’m going to try. I plan on bonding two quarter inch sheets so will be 1/2 inch or I might cut separate and then bond. It will be square then I want to cut out the centerpiece square. I want to be left with sqare with a big square cut oof center. I’m going to cut it like a 1/16 or so larger and then router it nice using a template. If anyone has experience working with acrylic what would you suggest for blade. I’m open to all advice. I may even try to cut it with the router rather than scroll saw at all. Not sure. Thx in advance for any help.

[kmmcrafts]

I've tried cutting it but it just wanted to melt back together, even at the slowest speed my saw would run.. guessing a skip tooth blade may have worked better? I think I was using a FD ultra Rev. blade.. anyway.. I found it worked best by sandwiching the acrylic in between some BB ply.. I never did finish my project with it.. so i don't know how it really turned out.. my sons friend was just trying to make a square to replace a window and I tried helping with it.. before I left to town.. so I don't know what they ended up with or if it even worked.. LOL

[John B]

I used to cut quite a bit of acrylic to use for photo frames and money boxes. It was only 3mm though.
I can';t remember the blade I used, but I do know it wasn't a reverse tooth as this tended to grab and lift the sheet.
I had to slow the saw down a bit to stop it melting back together. Always leave the protective plastic on while cutting, this also helps to stop it re-joining, not to mention preventing scratches. If the protective sheet is missing use clear packaging tape.
Oh and use safety glasses, as the dust eg splinters are hard and being clear it's the devils own job trying to get a piece out of you eye, (Enough said about that )

[fredfret]

Skip tooth non reverse blade. Slow saw speed, make sure to have a covering (see John's comment ) . I sometimes use a VERY small amount of mineral oil only on the pattern line for additional lubrication. Do not stop feed with the saw on it will cause edge welding. 

[Brianr24]

Thx for help. Hmmm sounds like this is not going to be easy. I’m going to have to do some experimenting. Problem is I need the entire sheet I have for the project. 

I may even think about cutting it into strips I need with table saw and weld it back together forming the square I need if that makes sense. I still have to router a slot in it. Maybe I’ll check out cutting it with a spiral up/down bit. I’m not sure  

[JTTHECLOCKMAN]

Not all acrylic is the same and plexiglass is just a version and generic name for it. I have no problem cutting acrylics on my tablesaw and use various blades. But they do make a non ferrous and plastic blade. As far as on the scrollsaw I too sandwich between some BB and cut using a standard #5 reverse tooth FD blade as I always use for just about everything. I have also cut without plywood and just use blue painters tape on front and back. An example is the acrylic mirrors cut for these.

 

Edited March 24, 2019 by JTTHECLOCKMAN

[Wichman]

Spiral blades work well for cutting plexiglass. Something about the structure keeps the blade from melting the plexi. To rip long sections of plexi, use an oscillating multi tool with a half round blade; I had to rip 8 ft strips once and the OMT did the job flawlessly.

 

[Brianr24]

Thx guys I used a polar # 5 (I think) I’ll chk later to make sure. I found it in FD assorted packs I had. It cut perfect super easy. It cut easier than wood. No melting or splinter.I wish I had known I would have made better lines and cut right to them and could been finish. But now I’m just going to trim with spiral pattern bit on the router.

[new2woodwrk]

I've cut plexi on my table saw many times with no problems at all. I use an 80T Diablo blade

I make instrument display cabinets and the doors are framed with plexi.in the middle.

If I had to do a cutout I would use jigsaw rather than my scroll - I think I can control the cut line easier with a jig myself.

 

[Roberta Moreton]

I just made a frame and used 1/8” plexi for the glass. The bandsaw with a 1/2” blade is what worked for me. Didn’t even think to try the scrollsaw. 

[aj43]

New to the Village. Haven't even introduced myself yet, but can share a tip I learned from other scrollers about preventing acrylics and other plastics from melting and rebonding after the cut.

The trick is to cover the areas to be cut with clear packaging tape. I probably overdo it by taping top and bottom.  The tape acts as a lubricant for the blade. Works like a charm. Can't remember which blades I used - probably a Flying Dutchman Polar #3. Whenever I needed help with what blade to use, I always got good advice from Mike's Workshop where I also get my FD blades. 

aj43 from Cincy.

Edited March 25, 2019 by aj43
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[OCtoolguy]

7 hours ago, aj43 said:

New to the Village. Haven't even introduced myself yet, but can share a tip I learned from other scrollers about preventing acrylics and other plastics from melting and rebonding after the cut.

The trick is to cover the areas to be cut with clear packaging tape. I probably overdo it by taping top and bottom.  The tape acts as a lubricant for the blade. Works like a charm. Can't remember which blades I used - probably a Flying Dutchman Polar #3. Whenever I needed help with what blade to use, I always got good advice from Mike's Workshop where I also get my FD blades. 

aj43 from Cincy.

Thankx and welcome to The Village aj. This is a great place to hang out.

 

[Chunkthekid]

I was very hesitant the first time I cut acrylic, but I used the FD polar like you and WOW, I couldn't believe how easy it cuts. It makes you realize how much the grain in wood can throw off your blade.

[CharleyL]

I cut it slow, so the blade friction doesn't melt the edge. If you have chipping or cracking, a finer tooth blade will help. Lexan is a better choice than Plexi because it doesn't chip or crack. They make bullet proof windows (much thicker) out of it.

Charley

[clocks and more]

I use clear packing tape, and have no problems.