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Subject: Re: [Homebrew_PCBs] AQ3000 Waterborne Photoresist questions

From: Larry Battraw <lbattraw@...>
Date: 2009-12-04

Thanks Robert, I definitely have pondered trying to spin it but I
don't have an old turntable lying around. I'd use a motor and try to
rig up a platform but it's definitely a challenge trying to rig up
something that doesn't fly apart or fling the board off. :-)

On Thu, Dec 3, 2009 at 5:02 PM, Robert Blumer <bob@...> wrote:
>
>
>
> Larry,
> I used Kodak AZ111 a long time ago, not available now but I used an
> old 78 rpm turntable and use an
> eye dropper to place it on the spinning pcb blank.
> to get a very even coat.
> Not sure this will help with your photo resist or not.
> Robert
>
> Larry Battraw wrote:
> > Hi, I recently bought the roller-coating version of this photo resist and am
> > having a terrible time getting a board to cure properly. What generally
> > happens is that the board will cure somewhat well except for a big, jagged
> > "rip" through the center of the board's resist. It looks like a ragged tear
> > in the resist and spreads out in sharp edges kind of resembling a lighting
> > strike with the streamers of the defect branching out. If anyone is
> > interested I can post a picture of the problem. Has anyone used this stuff
> > and had any success with it? I've tried diluting it since it tends to
> > capture bubbles like crazy when spread normally but that just results in a
> > pool of concentrated resist in the center of the board and decreasing
> > amounts as it reaches the edges of the board. I would really appreciate
> > some hints since the stuff has great potential to coat large/thick boards
> > that won't fit in a normal laminator with the dry film resist.
> >
> > Thanks!
> > Larry
> >