In the guide there are three methods described:
The PLA will gradually stiffen over the course of a minute or so after it has been removed from its heat source, so you will have a reasonable window in which to form the gauntlet. And the gauntlet can be re-formed at any time by repeating the heating steps.
- Toaster oven. It keeps the gauntlet dry and it is easier to handle without being covered in hot water. Set the toaster oven to a medium heat (200-300 F) and check frequently with a fork for flexibility and softness.
- Hot air gun / hair dryer. It's a little trickier to get even heating using forced hot air, but a hair dryer is very useful for tweaking the fit and re-working the form to get a perfect fit.
- Microwave with water. As PLA does not convert microwaves to heat very well, it is necessary to submerge it in a shallow bowl or plate of water to heat it. Microwave until the water is boiling and then remove with a fork or tongs when soft.
Prepare the arm by draping a piece of cloth over the area to which the gauntlet is to be fitted. Quickly remove the gauntlet from the heat source and drape over the arm and apply pressure to form the gauntlet to the arm. Check that the wrist pin hole are parallel and are at a comfortable location. You can either continue to hold the gauntlet in position until the PLA firms up, or you can hold the arm and gauntlet in place in a sink and run cold water over both to set the form of the gauntlet.
Detailed guide is here:
http://www.instructables.com/id/Thermoforming-3D-Printed-PLA-for-Use-in-Prostethic/?ALLSTEPS
Heating PLA water emerged in microwave owen |
Forming PLA to fit your body (hand) directly with wet towel |