Get Bent! Bending Plastic with a heat strip bender!

Bending plastic is fun and exciting...ok, the amount of enjoyment may vary from person to person...but you get the idea.

All you need is plastic and a heat bender. Luckily, i have access to a heat bender at TechShop in San Jose, CA.

As a note, you should always do a test to make sure that your plastic can be heated and formed. Some plastics like poly carbonate with show black specs when heated, and these will not go away. In addition, I do not recommend heat bending material more than 3/8s of an inch thick.

Anyway, you have to bend plastic, and you want to do it right, so this is the place for you! Now, onward, to the instruction!

Step 1: Prep! Removing Protective Film and Marking the Plastic for Meassurment

When handling sheet plastic, it is always best to keep the protective film on it for as long as possible to avoid scratches. Because we are going to be applying thermal energy to the plastic, you must remove the film. If you do not remove the film, the film will melt to your plastic will be nearly impossible to remove. Remove the film only along the area you will heat bend so that the rest of the plastic stays in good (unscratched) shape.

The easiest way to mark your plastic is to use a sharp knife. Carefully mark the areas you want to bend with a light scratch. This scratch can be buffed out, or will normally just melt back into the plastic during the heat bending process.

Comments

[servant74]

We made one similar when I was a kid. Made a plywood surface and got some asbestos paper (used as underlayment for siding at the builders supply at the time) and stapled it to the top of the boards with folding it to line the channel, and laying the heat tape in the channel. Hooked the tension loops on the tape on nails or screws at each end and plugged it in. The wood underneath got warm but never near charring, and the heat tape looked like the one TAP sells today. ... Yea, you can't get asbestos paper anymore, but such is progress. ... Oh yes, this was about 55 years ago if I remember working on it with my Dad in the garage. ...

We built all kinds of things, wind tunnel, demonstration NMR rig, simple EDM machine (from plans in Popular Science), etc. I even remembering getting a 5lb vial of Mercury and letting my younger brothers play with it on the kitchen table. Eventually we made a barometer out of it. ...

All the kinds of things CPS and OSHA and HAZMAT teams would be all over us for these days. ... My sons cub scout leader would be hauled away today for using a 'trick' with brake fluid cleaner to start a fire these days (it generates sarin gas when heated near burning as it's default break down, so never use break cleaner to clean metal before or after welding while it is hot. I have heard from a couple of welders that had a close call and permanent neurological damage by accidentally doing this. Carburetor cleaner is OK, just not brake cleaner.)

[andybuda]

so you only need to heat one side the side that stretches not the side that compresses i would have loved to make some perspex speakers but i have to many and the cost of a mistake

[pcooper2]

I built my own strip heater over 20 years ago, using a flexible heating element I purchased from TAP Plastics in San Jose, California. The support structure was made of 1/2-inch plywood, and the channel in which the heater lies was lined with ceramic fiber board obtained from a local hardware store. The ceramic fiber board was glued to the plywood using silicone caulk. Simple cheap, and works well with acrylic sheet goods.