Homebrew PCBs

Does Datak mention anything about using a "sunlamp"...something with 
some UV spectrum in it? That's what I used in a silk screen method 
with photo-emulsion and tracing-paper/toner mask. About 10 minutes 
exposure at a distance of about 20 inches or so (depends on how new 
the sunlamp is)

Hope this helps,

Bob





--- In Homebrew_PCBs@yahoogroups.com, "ednspace" <ed@c...> wrote:
> Hello,
> 
> This is a plea for help!
> I am on my 5th trial with this and while each trial improves 
somewhat 
> in end quality, and certainly in the process, (no longer spilling 
> solvent all over the basement), I still have yet to produce a board 
> that I thought could be etched.
> 
> The traces are very weak to washed out to non existant.  At first I 
> thought I was under exposing now I suspect I am over exposing or 
just 
> not getting a good build up of the resist on the board to start 
with.
> 
> I am looking for someone familiar with this method to bounce a few 
> emails with so that I can get it right.
> 
> At this point I am:
> In a 60watt bug light environment (Problem?)
> Coating the boards with makeup swab rather then spraying, much nicer 
> coat and no smears, nice and shiny, dust free mostly.
> 
> Drying over night in a sealed shoebox, inside another box
> 
> Using tracing paper as negative nice black laser print (Reported to 
> work in many places)
> 
> Exposing with a 250watt photoflood for various times and developing 
> following supplier instructions with the recommended developer.
> 
> Exposure times have been, 22, 10, 5 with a couple of retrials in 
> between, no, luck.  Any help would be greatly appreciated.
> 
> Thanks,
> Eric