On Jun 18, 2009, at 9:46 PM, William Beaty wrote:
On Thu, 18 Jun 2009, Horace Heffner wrote:
The price of CR-39 is quite bothersome for amateurs like me though.
It would be good to find a cheaper alternative!
I have a couple pounds of it, 1.5mm thickness, unknown age. I only
just
started playing. I found that you can't mask it off with
scotch tape during etch, the adhesive dissolves. Also it seems to
etch
asymmetrically unless the chips are positioned vertically in the bath.
The samples I tested have 50-100 tracks per mm^2. Gonna try
resetting the
latent tracks by heat soak above 100C, or even melt some.
Did you see the cure cycle here?
http://tinyurl.com/yp6ld5
http://corporateportal.ppg.com/NR/rdonlyres/
3161A365-5C86-484F-97B6-74059920D2B6/0/CR39.pdf
Polycarbonate is also said to work. Originally discovered in
Apollo crew
helmets, Lexan?
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
