Homebrew PCBs

DJ Delorie wrote:
> Ok, shame on me, I broke the glass in my UV box.  Too much vacuum.
> We've checked a few local places, the glass they have has UV blockers
> on it.  I've got more places to try, but I thought I'd ask...
>
> What else can be used besides glass, which will still pass UV without
> bending or blocking it?  Something less brittle, more flexible, but
> still stiff enough to mostly hold it's shape (my UV box has a foam
> gasket along the outside edge of a piece of plywood, the glass rests
> on it and is sucked down onto the board).
>
> Even rubber-like flexibility is OK, I suppose - I can make a wooden
> frame to hold the edges and use an even thinner gasket, but that's
> more work, and it means I have to cut up my films into individual
> sections so I don't bend or crease them from the shrink-wrap effect.
>
> DJ
>
>   
There used to be (and I assume still is) a clear plastic - acrylic or 
polycarbonate? - that was labeled  UVT for UV transmission or UV 
transparent.  I believe it was made by Rohm and Haas.  TAP Plastic may 
stock it.  A quick Google for UVT Plastic yielded:
www.polymer*plastic*s.com/transparents_*uvt*a.shtml,
plus a bunch more.

Norm
W6NIM