Instructables

Plastic Bottles?

I would like to melt them in an oven,and have them slump around a mold. At what temp should the oven be set ?

Gorfram4 years ago
You can usually figure out what kind of plastic you have by finding its little recycling triangle and seeing what its recycling number is.

Two-liter soda bottles are usually Recycling # 1 (also known as PET or PETE). PET usually doesn't melt below 500 F, but may shrink or slump  at much lower temps (starting around 150 F). The good news is that it generally emits  little or nothing in the way of fumes.

You may have better luck with milk jugs and/or plastic bags. #2 (HDPE) & #4 (LDPE), which melt over a range of about 200 F-265 F. They emit little or nothing in the way of fumes; and since they are both the same basic kind of plastic, they can be melted together.

Number 5 (PP) melts around 320 F, but may sometimes have additives that emit harmful fumes.

Number 6 (PS) melts at 465 F, but often has additives that produce fumes that are much better avoided.

Number 3 (PVC or V) melts around 220-265 F, but always produces very nasty, harmful, dangerous fumes - Don't Try This At Home, Kids. DANGER, WILL ROBINSON! AVOID AVOID AVOID.
Re-design4 years ago
Depends on the plastic.  You will have to experiement with what you have.  Watch closely, lots of plastic goes from rigid to flexible to burned and ruined your mother's stove very quickly.