Smoothing Cut Edges on Clear Acrylic

Sander, router, jointer, or torch many methods can be made to work. August 30, 2007

Any tips on finishing edges on Plexi? I've been asked to cut some Plexi, and the money is good, so I'm going do it. I hope I'm not in for a hard time. I'm thinking about scraping them clean with a razor blade.

Forum Responses
(Laminate and Solid Surface Forum)
From contributor J:
With Plexiglas you can also sand the edges smooth, which is what I usually do. If you want that clear, rounded edge, there is a method of lightly heating the edge with a torch which is supposed to work well. Can't say I've had much success with it myself, though.

From contributor O:
I've used a router table with a bit to do similar. I run the edge though the middle of a large beading bit to give the edge a slight smooth outward bow. I would think you could cut it slightly oversized on the saw, then dimension it with a straight bit in the router table. I haven't found a blade on the saw that doesn't cause a fair amount of chipping. The router cleans all that up.

From contributor M:
I have had great success using a jointer. Yes, it does work! Just a few thousandths of a cut and sharp blades. I first run them through a router table with a roundover bit all edges, both sides, then just kiss them through the jointer, and poof - done - and looking great.

From contributor D:
The torch method works really well once you get it down. It gives very smooth edges. You can also progressively sand it similar to automotive clears and get a very highly polished finish.

From contributor C:
Plexi fabricators like to use a hydrogen torch (clean flame) to polish edges.

From contributor L:
The process is called "flame edging." I do it sometimes on acrylic (Plexiglas). First run it through the jointer to clean up the edge. (If it's an irregular shape, use a router and pattern bit). Next, peel the paper backing away from the edge of the acrylic. An inch or two is good. Now, using a propane torch with a smallish flame (simple bernz-o-matic is fine), heat the edge of the piece until it turns clear. Just make sure to keep the flame moving and not staying too long in one spot. A local pro shop uses a combination of propane and oxygen to do their flame edging. Propane alone works fine. Don't use acetylene, as it is a "dirty" gas and will muck up the results. Maybe mapp gas would work, I dunno. Apparently polycarbonate (Lexan) needs a different gas setup (hydrogen?). Experiment a bit, it's pretty straightforward. I don't know where you are located, but Google "Tap Plastic." They are a consumer friendly supply house. More geared toward homeowners and weekend DIY-ers (and expensive to boot!), but they are a good source of info with no attitude.