Homebrew PCBs

Thanks for the info.


----- Original Message ----- 
From: <JanRwl@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, January 11, 2006 1:28 PM
Subject: Re: [Homebrew_PCBs] Totaly OFF topic .. but who cares. (case front 
panels)


>
> In a message dated 1/10/2006 7:01:40 P.M. Central Standard Time,
> pharmapack@... writes:
>
> what  kind of "photo-sensitising" you did on the
> aluminum.
>
>
>
> This was at least 25 years back, but I THINK I used the  General Cement 
> (?)
> firm's photosensitive spray.  It comes in a small  aerosol can, and sprays 
> on
> as a transparent pink, and one must of course do that  in subdued light. 
> Then
> cover it with a box or something to let it dry  overnight.  The stuff I 
> used,
> as I recall, had to then be exposed with UV  or sunlight for a 
> considerable
> time, compared to "photography exposing", with  the negative-film held 
> flat on
> it in a contact-exp. frame.  I have since  seen pre-sensitized PCB stock 
> in
> 4x6" and up pieces advertised on the ad-pages  of hobby-electronics type 
> mags.
> NO clue how those work; faster, or  what.
>