[HH] How To Heat-Bend Acrylic

[Tom Metro]

In Make's Workshop Wednesday column they demonstrate How To Heat-Bend
Acrylic. The demo project is a clear plastic display case for a toy, but
obviously the technique can be applied to other things.

http://blog.makezine.com/2013/02/06/workshop-wednesday-heat-bending-acrylic-enclosures/

  Acrylic has great potential as a building material for would-be
  makers. It has a very clean look, is easily cut (dremel, table saw,
  scroll saw, band saw, to name a few), and is durable.

  When building your own creations, it's sometimes necessary to bend the
  acrylic sheets themselves in order to serve your vision. This can be
  easily done using little more than scrap wood, a Dremel, circular saw,
  heat gun, and a vise.

I remember building a pencil holder or some such in Junior High shop
class out of acrylic. Then later in the class using the same techniques
to build an underwater camera housing. (Unfortunately I made it rather
roomy inside to accommodate a flash, which made it too buoyant, and the
flash probably would have just bounced off the inside of the enclosure.)

To bend the sheets of plastic, you'd place them over a device with a
single rod-shaped heating element for a while, then bend and hold in the
desired position until cool.

The article and video illustrate using a head gun, with some scraps of
wood placed on the plastic sheet as a sort of heat shield to focus the
heat along a single strip. They also took the extra step of creating a
wooden form, cut to the desired angle of the finished bend, to support
the softened plastic in the correct position.

I don't remember what means I used in Jr. High to cut the sheets, but
here they seem to use a cut-off wheel on a dremel tool free-hand. The
finished cuts look straighter and smoother than I'd expect from that
approach. But who knows if they skipped showing intermediary steps, such
as using a stationary belt sander to smooth off the edge.

It seems the best approach is to use a table saw, providing you use the
right blade type to minimize chipping. For small cuts I've found a steel
ruler and a utility knife will make a straight and smooth cut, but it is
quite tedious. The hardware stores sell a cutting tool made for this,
but it is effectively like a utility knife with a thicker blade. I'm not
convinced it'll work better, but I haven't tried it.

 -Tom