Molding Plastics


What is the easiest plastic to mold and shape once heated, and that is fairly strong once cooled down.

I was thinking of polystyrene form yogurt tubs or CD cases, because apparently if you heat it above 95 degrees it is easy to extrude and form

I want to make a connection to a valve which will make it easier to glue a rubber tube onto. I also want to glue the custom made connection onto the valve i just have to make sure it fits nicely 1st.

Also is it dangerous to heat plastics? are harmful gases if they are heated using an open flame?
If there any other safety factors to conciser please let be know :)
Not sure of the answer, but I would google plastic thermoforming for info. As far as danger factors... They do release gases, but if your just heating small peices I wouldn't imagine it would be that great of a danger. I used to work in a thermoforming plant and the air would get hazy with exhaust from the process... No one died or was injured, so there are no immediate health risks. Couldn't tell you about long term effects though.
A great plastic material is polycaprolactone. It can easily be melted with hot water and shaped by hand into any form. And it's very strong once it has cooled down.
Here is a video showing how it works
It's sold in the US as "Shapelock" ( But their prices are way too high.
The cheapest price I've found so far is on But I don't know if they ship outside of Germany.
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