any experience with curving lexan/plexiglass

[abt]

making a curved footboard/cabinet for childs bed and want to make curved 'glass' doors. is it possible to heat lexan and mold or will it scorch? Thanks

[Hambone Slim]

Lexan is polycarbonate sheet, which is a little more difficult to work than acrylic sheet such as plexi or acrylite. Either can be heated and bent to a radius. They will scorch and bubble if overheated.

-- Timothy Juvenal

[Tyke]

My limited experience is with making a small box for an aquarium from acryllic, not sure it it was Lexan. Aquariums are built from many plastic materials, not sure about Lexan.

I expect Lexan is able to be molded with heat. You need to control the heat. I used a heat gun which is an electric heater element with a fan to blow the hot air. The challenge will be getting the same heat across the material so that it molds consistently.

Too much heat and you will see bubbles before scorching. Using a propane torch is likely to be too high a temperature and could scorch or melt the Lexan.

You could try making a plywood mold, laying the Lexan over the mold and then gently applying the heat gun until the Lexan starts to drop into/over the mold as the temperature reaches the point where the Lexan is flexible.

Tight radius is possible, but will take practice.

Dave Paine

[Edwin Pawlowski]

Possible? Sure Practical? Not so easy.

You can build a "mold" or mandrill to wrap the softened plastic once heated. I'm not sure, but polycarbonate softens at about 270 degrees. If the sheet fits in your oven, you could heat it, shape it, then let it cool in place.

[CW]

I think you have that backwards as for working properties.

[Hambone Slim]

Years back, when I was working with plastics, we usually worked with acrylic and were familiar and comfortable working with it, as well as with styrene. We weren't as familiar with polycarbonate, and it didn't work well under our usual acrylic techniques. In particular, I remember polycarbonate having a greater tendency to burn while cutting, and clog the blades, and it being impossible to score and snap. I seem to recall it was difficult to flame polish also. Maybe thermoforming is easier? which of course is what the OP wanted to do, but I don't recall.

-- Timothy Juvenal

[CW]

[Frank Boettcher]

How far do you need to go. what radius. If it is in a frame you can cold bend it a fairly good bit.

It also cuts and shapes well with standard woodworking tools.

Frank

[gfretwell]

I made a scraper for my pontoon boat from a big lexan ice scraper. I put it in boiling water and it was easy to mold it to the shape of a pontoon. It is just starting to be soft at 100c

[Ioan Barladeanu]

You 'll want to make a mold against wich you'll press the heated lexan sheet. The process doesn't require any extraordinary skills, as long as you heat it over a large surface. If you make many of those curved doors, you could build a heater for that at very little cost - something similar to the heating element used in this DIY vacuforming table

a hot air gun for a large surface won't be very good, but it's still possible. Depending on size, you might want someone to help you hold the lexan sheet / press it onto the mold. Another usefull thing is to screw two

1/1" pieces of wood on the long edges, that would help you get an even pull on the sides (you'll leave that sheet bigger anyway - trim it after it's been formed). I hope I've made myself clear, even though english is not my native language :-P

[Ioan Barladeanu]

Oh, and DON'T use a flame torch to heat it.

[CW]

[klaatu]

Lexan must be baked at a low temp. befor raising the temp enough to bend it. Try 150 to 200 degrees for 12 hrs on a test piece. The reason is that Lexon has a lot of water in it that must be driven off at a low temp. That is the same reason that oil or gasoline make Laxan brittle. They replace the water. Plexi doesn't have this problem.

[Andy Dingley]

If you use a heated mandrill, it'll bite you.

Avoid Lexan / polycarbonate and stick with acrylic / Lucite / Plexiglass / Perspex. Much easier to work with - or rather not "easier", but much more likely to be successful.