Plexiglass cutting?

[wolfb]

Anyone familiar with plexigalss cutting? Typically the sheets come in .08 or .10 for most applications like picture frames, replacement panes etc. I'm not sure what they are measured in as .08 is just about 1/6" or a little less than 3mm. I have had some success with a utility knife...scoring along a straight edge and then snapping the plexiglass, but that is not very clean. I have previously tried using my table saw, but I must have used a blade that was to course as the plexi chipped no matter how slow I fed it. I know of the old trick of turning the blade backwards and basically burning the piece. How do you all do it? Any good pointers? Cheers! Wolf-==-

[stoutman]

Google in 'Groups' for "cutting plexiglass"

tons of info. It has been discussed in this group several times.

[Doug Miller]

A 40-tooth combination blade (10" Forrest WW2) works fine for me...

If you use too fine a blade, you'll melt it. And then you have a real mess.

-- Regards, Doug Miller (alphageek-at-milmac-dot-com)

Get a copy of my NEW AND IMPROVED TrollFilter for NewsProxy/Nfilter by sending email to autoresponder at filterinfo-at-milmac-dot-com You must use your REAL email address to get a response.

[DanG]

A sharp blade in a table saw has always given me good results. You can sure tell when the blade is not sharp!!!!!

It also helps to use a zero clearance insert or put your plastic on a sacrificial scrap of plywood.

If you want a really nice edge, run it past a router bit. It will not work well for cutting the material - it tends to get the plastic hot and stringy, but it great for taking a light finish pass.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[Dave Carnell]

A sharp blade in a table saw has always given me good results. You can sure tell when the blade is not sharp!!!!!

It also helps to use a zero clearance insert or put your plastic on a sacrificial scrap of plywood.

If you want a really nice edge, run it past a router bit. It will not work well for cutting the material - it tends to get the plastic hot and stringy, but it great for taking a light finish pass.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

You want a really thin carbide-tipped blade to get a smooth cut with no melted flash.  The Matsushita 7¼" combination blade is perfect for this.

In Boatbuilder, May/June 98, Thomas Firth Jones said about cutting acrylic sheet “Myself , I’ve fallen in love with the 7¼” Matsushita blade...It doesn’t have that many teeth but whatever you put through it comes out looking as if it had been planed and its 1/16” kerf makes light work of ripping heavy teak as well as plastic.  It’s my best new tool in years.”  They are available from various sources, but I also sell them.

Dave Carnell

[Joe Bobst]

Done it for years with table saw, scroll saws. kjig saws, by hand. In every case, very sharp blades is the key ingredient. Drilling holes IIRC involves special drill angles. Most plastic supply houses will have access to manufacturer's publications and some helpful hints, too. Check the NG archives here as there may be better answers to your questions. HTH

Joe

[Dave Carnell]

You want a really thin carbide-tipped blade to get a smooth cut with no melted flash. The Matsushita 7¼" combination blade is perfect for this.

In Boatbuilder, May/June 98, Thomas Firth Jones said about cutting acrylic sheet ?Myself , I?ve fallen in love with the 7¼? Matsushita blade...It doesn?t have that many teeth but whatever you put through it comes out looking as if it had been planed and its 1/16? kerf makes light work of ripping heavy teak as well as plastic. It?s my best new tool in years.? They are available from various sources, but I also sell them.

Dave Carnell

[Ulfius]

Just did this last week on my Jet contractor's saw with the stock blade. The blade is still sharp though. The technique that worked best for me was to have the blade height just above the top of the plexiglass and I also sandwiched the plexiglass between two pieces of scrap wood. In my case, the bottom board was my panel jig and a piece of mdf above the plexiglass. The edges turned out a little sharp, so I took a file at a 45 degree angle to it to soften them.

Shawn

wolfb wrote:

knife...scoring along

[RonB]

I just cut several pieces and at the merchants suggestion I:

1) Scored it, with pretty firm pressure, 8 to 10 times with a box knife. 2) Hung the cutoff area over the edge of the bench with the score at bench edge. Place a rigid straightedge or board, also even with the score and bench-edge, and held or clamped firmly. 3) Pushed the cuttof down smartly and quickly.

Most of the cuts came out looking pretty good. I did have to dress a couple of areas with sandpaper. This was with 1/8" material.

[Bill Stock]

I had good luck cutting it with a plain plywood blade (200 teeth). I fed it at a good speed with the blade about 1/8" above the plastic. Unfortunately I was ripping a "cutoff", which had no straight edge. So now I have to use the router and a flush trim bit to clean up the edge. I've been waiting for some warm weather, so I can do this in the garage. Cutting this stuff inside (basement) really smells up the house.

[Phisherman]

For thin Plexiglas use a bandsaw. Use lots of ventilation. I have cut 1/4" Plexiglas on my table saw without any problems.

[Jim K]

For thin stuff, go ahead and splurge on a plexiglass knife. It's basically a sharp hook-shaped knife. You can score the thin stuff and snap it easy. I've cut a bunch and had no problems.

[Glenna Rose]

That's the method I used, to sandwich the plexiglass between two pieces of thin plywood (1/4" I think, it was 1982) and use a fine blade in the saw (used the saber saw [jig saw?], trusty ol' Craftsman and a guide) . I cut several pieces and all had nice square edges without "jags" so I must have done something right. The project was a desktop divider for files, to hold them horizontally, and had three columns of shelves so there was a lot of cutting, at least 40 cuts. I likely used a sanding block with fine grit sandpaper to finish the front edges as an extra. Used the unit in my office; it still looks good. I absolutely loved to be able to just glue it all together, no nails or staples! It seems that it didn't smell very good when it was cut and I kept the doors open, grateful it was warm weather.

I'll find out how well my memory serves me in a couple of months as there is a plexiglass project in my fireplace mantel's future. I have no place for the full-width mirror that is there now and want shelves on which to put photos, etc., above the fireplace. The mirror will stay there but I'll put shelves on each side and across the top (the mirror is 7 ft. x 3 ft.). I'll use clear tubing for the spacers between shelves which should work well. The full-length shelf across the top will be addressed differently and might be attached to the ceiling for support or just not done at all; that'll be determined when the others are in place. A decorative panel of some sort might be a better choice and only for balance.

Good luck on your project. Do let us know what you decide to do and how it works.

Glenna