[sdiy] Photosensitive PCB's

[maxpowa.telenet.be]

I use positive pre-coated PCB by Bungard. I print my artwork on tracing
paper by Canson (cheap, packages of 12 sheets A4 format) with a laserprinter
at 600 dpi. Expose it with a homemade UV-box with 2 tubes i bought at my
regular electronics store (about €15/tube) for about 5 minutes. This works
like a charm, did the finest of artwork with it (including SMT artwork).
This method using these tools and materials has never let me down.

Steven

----- Original Message -----
From: "Michael Schulze" <michael.schulze at oberlin.edu>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Friday, May 24, 2002 6:08 PM
Subject: [sdiy] Photosensitive PCB's


> I'ma having a hard time getting the photo sensitive pcb process to work.
> I've sprayed my own boards and exposed them with negative art.  When I
etch
> there seems to be not enough contrast between light and dark, so the
traces
> are not clearly defined.  By the time I can see the fiberglass in between
> the traces the traces are half gone too.
>
> Maybe I am spraying too much coating on???
>
> I've ordered the positive boards to see if that is easier.
>
> Any suggestions on suitable light sources for positive vs. negative
boards?
> Seems sunlight is too unpredictable - 4 minutes of noon sun in Ohio is not
> the same as 4 minutes of noon sun in Florida!
>
>
>