Want to bend sheets, tubes, sticks of plastic?
Don't want to buy a 200 dollar heating base?
Build one for pennies! (free if you go dumpster diving)
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Step 1: Materials and Tools
For a totally free unit, dumpster dive for these materials:
- Toaster oven (cylindrical, rod-like, non bent, heating elements)
- Sheet metal (I used old brass door kick protectors)
- Outlet plug (old extension cord or whatever)
- Light dimmer
- Wiring nuts (or soldering gun)
- Liquid electrical tape (optional)
- metal pipes (optional)
- Garden Shears (or anything that cuts sheet metal)
- Dremel or drill
Step 2: Dismantling the Toaster Oven
Rip apart the toaster oven. Bash it, unscrew the case, use the jaws of life, just dismantle the oven and retrieve the heating elements. Keep as many as possible, because you can make the heating strip as long as required.
Step 3: Building the Base/heat Strip and Wiring.
-Take the sheet metal (must be longer than the heating element, or series of heating elements if you wish to make the heat strip longer) and cut out tabs to be bent perpendicular to the rest of the sheet metal.
- Drill holes on the tabs to thread the heating element through.
- Wire one lead of the power cable to one lead of the dimmer switch, and the other lead of the dimmer switch to one lead of the heating element.
- Wire the other lead of the power cable to the other lead of the heating element.
- (Since the heating elements work on A/C current, you can disregard rectifying the current, and you can disregard which lead of the power cable goes to which lead of the dimmer or heating element.)
- Mount metal pipes (with nuts and bolts or cut tabs on the sheet metal and bend them in towards the pipe) parallel to the heating element, with an about 1 inch gap from the element.
- Apply liquid electrical tape to seal any exposed wires (don't want to be electrocuted. I used tape)
Step 4: Using the Heat Strip
Without the optional metal pipes:
- Turn on heating strip, adjust the dimmer for the right temperature (I usually turn it on all the way, then reduce the heat.)
- Hold the sheet of plastic hovering about half an inch over the heating strip. The edge of your intended bend should be parallel to the heat strip.
- Once the plastic starts drooping just the teeniest bit (you may also try and bend the plastic a bit to judge when it's good enough to start bending), move it away from the heating strip and bend. You may use a jig for definite angle bends. (I use square wooden dowels for right angles. I pin one against the bending edge and slide the other dowel under the soft plastic to fold and keep it at a right angle.)
With the metal pipes:
- Same as before, but you do not have to hold the plastic sheet while the plastic is softening, just leave it resting on the metal pipes.