printed circuit board exposure/now pcb revelation!

[Rob]

Well, in response to all concerned, I have figured out the problem..

1. Dont believe what they say at the surplus house about whether or not the
board has photoresist already on it.. I figured out it didnt after talking
with a friend who works for the company they got the boards from.

2. Even though they do make photoresist boards that are quite stable under
flourescent and incandescent light, if they don't still have the mylar
wrapper, they ARENT photoresist anymore. BEWARE.

3. If you have a thermal wax printer, you dont need to buy photoresist pcbs
anyway.. My Alps seemed to do a good enough job for me to print to an
overhead and then use an iron to transfer the wax from the printer to the
pcb! Wow.. what a stroke of luck buying this printer! ;) Mind you, I had to
touch it up with a sharpie permanent marker, but it was still MUCH easier
and quicker than doing all the gobbledigook required to get an accurate uv
exposure anyway..

So, I ended up with a decent (but by no means good looking) pcb board!

I also learned that a big narrow, tall mason jar with the glass latching
sealed lid makes a GREAT etching enclosure!

So good, in fact, that I etched my first board clean (no traces, nada)
before I even got a chance to think to look to see how it was doing! Being
able to swish the FeCl around at a decent clip without worrying about
spilling it made it etch VERY quick.
Heating the etchant to about 130 degrees F and using the Mason jar worked
really great.

Thanx to all for the other methods!

BTW, I didnt spill or get ANY FeCl on me.. I love that mason jar.. ;)

Rob


----- Original Message -----
From: Paul Perry <pfperry at melbpc.org.au>
To: Rob <cyborg_0 at iquest.net>
Cc: <synth-diy at mailhost.bpa.nl>
Sent: Thursday, January 03, 1980 6:51 PM
Subject: Re: printed circuit board exposure


>
> Rob, I saw somewhere that most 'blacklites' for posters etc have
> only the 'near UV' & wont expose a board.
>
> You will have to make a 'test strip' by moving a metal sheet
> around so that you have exposures of 30 sec, i, 2,...64 minutes.
>
> I'm using press&peel blue for my prototypes, BTW.
>
> paul perry melbourne australia
>
> If yu DO go the sun route, the forst thing to build might be an
integrating
> UV exposure meter! (not joking)
>
>