Vacuum forming - what sort of plastic?

[bigegg]

I'm looking to experiment with vacuum forming.
I have the vacuum pump.
I've been reading up on it, and I basically mount the plastic in a frame,
put it in the oven until it goes soft, then place over the mold and vacuum it.
The formed sheet will then be filled with expanding foam to strengthen it, so thickness is not important.


That's the easy bit!

Difficult bit:
What sort of plastic?
I have some heat shrink pallet wrap - would this work?
What should I search for?
I'll be needing the equivalent of around 100 a3 sheets -
If I can get a 25m x 1m roll of something for around £30-£50 I'll be very happy!

Ta

 

[james butler]

http://www.technologysupplies.co.uk/materials/vacuum-forming-sheets/standard-hips-sheets.html

 

[bigegg]

The very limited amount of vac forming I've done always used a rigid sheet of plastic.

As the sheet gets thinner when formed (it's stretched over something, it has to) then starting with a roll of something like shrinkwrap means you'll end up with nothing...

If it comes on a roll, why would it not be floppy after forming?

I sort of assumed that the floppiness would be reduced by the forming.
The sort of thing I'm after is the equivalent of the plastic tray in a selection box or tin of biscuits

 

[500e]

http://www.technologysupplies.co.uk/plastic-offcuts-20kg-pack.html

 

[bigegg]

Around 1in depth of draw maximum.
It's an experiment to make some formed tool trays
If it works, I have around 100 drawers of stuff to fit.

 

[Keith 66]

I use a vacuum former at school quite often, it has an infra red heater that pulls over the sheet. once its reached temperature you lift the former up from underneath & apply the vacuum, car must be taken to allow adequate taper or draw on the mould.
Plastic used is generally High impact polystyrene. Might be worth looking out for a secondhand machine.

 

[Kayos]

I used one in a dim and distant past and learned that thin Perspex forms very nice, however once set it shatters if you look at it too long

 

[julianf]

There are eBay sellers who do the plastic.
Used machines seem.surprisingly expensive for what they are.

 

[bigegg]

Just as an addendum to this thread, before I post up the results in the 'projects'
It would appear that practically any sort of plastic can be used:
I'm going to try 2l pop bottles (which give a clear sheet about 6" x 8"
I also have a 5l fabric softener bottle.
Ifit works, I can get a steady supply of 25l chemical drums which used to contain isopropyl alcohol to cut up.