Thank you psykhon (and Terry and Andrew)!
With all of you saying the same thing I had another shot at drying before curing.
I tried 100C (my oven won't go lower) for 10/20/30mins but the mask was still not touch dry so I left it to cool overnight.
After 10 hours it was just about usable but still not totally dry. It exposed well but I couldn't put much contact pressure on for fear of the artwork sticking so some 5mil test lines were blurred. At any rate, progress has been made.
I think the real lesson I've learned is that the mask is designed for stencil printing only; quick drying isn't a priority as it's not intended to have anything in contact with it when curing. If only I was adept at making silk screen stencils!
Regards,
Bob
--- In Homebrew_PCBs@yahoogroups.com, psykhon@... wrote:
>
> +1, try 70-75 celcius for 20 minutes, then expose, develop, wash and final cure at 120-150 celcius for 40-60 minutes. most uv mask works this way
>
> --- In Homebrew_PCBs@yahoogroups.com, "Terry" <twgray2007@> wrote:
> >
> > I agree with Andrew...all the stuff I have seen, and used, have had an oven drying step before UV curing.
> >
> > --- In Homebrew_PCBs@yahoogroups.com, "Andrew" <a_wake@> wrote:
> > >
> > > Bob,
> > >
> > > Do I understand correctly that this process does not include a drying step? With other processes I believe you apply the liquid, dry it in an oven, and then expose it with the artwork. It sounds like the problem you are having is dealing with the wet liquid. Wonder what would happen if you let it dry first? Would it still develop under the UV?
> > >
> > > --- In Homebrew_PCBs@yahoogroups.com, "storan4wd" <bob.balderson@> wrote:
> > > >
> > > >
> > > > > But you COULD put an image on it, and have the soldermask only placed
> > > > > where you want it. Then just expose the whole board. Wouldn't that be
> > > > > easier?
> > > > >
> > > > > Kerry
> > > > >
> > > > You're right, that would certainly be possible but it's another time consuming procedure to make the screen and it uses limited shelf life chemistry. I have tried it for component legends but with only limited success (I found it very difficult coating the mesh evenly and at the right thickness).
> > > >
> > > > Bob
> > > >
> > >
> >
>