Re: Vacuum Forming --- Was--->Lights and lenses, the poor mans laser?

Thanks Graham, and also the person that responded offline. I did
reply to your email but I got a message back that it bounced.

Chris


--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Graham Stabler" <eexgs@...>
wrote:

>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "lcdpublishing"
> <lcdpublishing@> wrote:
> >
> > Graham,
> >
> > I have been wanting to try some vacuum forming for a while now.

Can

> > you give me a quick rundown on the process? I am planning to

make a

> > molded cover for the back of my machine (the one on the home

page).

> >
>
> I'm not much of an expert, I'm only making really tiny parts. Like
> any other forming technique it comes down to the mould. It needs

to

> have a nice finish if you expect a nice finish (though thick

plastics

> will still have a nice finish on the other side). You need to add
> releif angles so you can get the part off etc. Lots of stuff on

the

> net about this.
>
> The plastics are normally styrene, abs and even polycarbonate

though

> the latter will tend to bubble unless you bake the moisture out of

it.

>
> For heat the lamp did work really well, before that I put the

plastic

> in a frame and stuck it in a little oven but I much prefer this.

The

> plastic goes through various phases, it buckles, tightens and then
> droops, you form on the droop. Positive and negative moulds are
> possible, negative is better for deep stuff, they sometimes even

suck

> and blow.
>
> A shop vac is what I use.
>
> Graham
>