Homebrew PCBs

On a side note, if you have a KitchenAid or similar oven with electronic
control, look under the options menu for a "Dehydrate" mode - that should
allow you to set temperatures lower than 100C

Andrew Hakman

On Mon, Feb 20, 2012 at 6:45 AM, storan4wd <bob.balderson@...>wrote:

> **
>
>
> 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
> > > > >
> > > >
> > >
> >
>
>  
>


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