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Subject: Re: silicone coated paper - Another test

From: "ballendo" <ballendo@...>
Date: 2005-03-27

How about using silicone mold release spray? (The composities
industry uses it by the "boat"load<G>)

Not oily, and dries hard Any place that sells fiberglas (FRP)
supplies should have it.

Hope this helps,

Ballendo

--- In Homebrew_PCBs@yahoogroups.com, "javaguy11111"
<javaguy11111@y...> wrote:
>
> After seeing Stefan's results I had to try the silicone paper idea
> myself. The silicone I used was GE Silicone I Clear Kitchen and Bath
> which I bought at Lowes.
>
> I did make a few changes to the process. First I used transparency
> instead of paper so I could see what was going on. Also in an
attempt
> to get as even a coating as possible I taped down a few extra pieces
> of tranparency for my putty knife to ride over to get an even
> thickness. I also used transparency because I wanted to rinse down
the
> silicone to remove any residual acetic acid from the curing. I am
not
> sure what that may do to the drum or fuser.
>
> My results were not as good as Stefan's. First the coating did not
> come out as smooth as I would like to have seen it. It tended to
have
> some ripples and bubbles in it. When I ran it through my HP 1300
laser
> printer I get a lot of toner dust scattered around. The image itself
> looked okay.
>
> I then ran my silicone coated transparency through my laminator with
> the circuit and most of my image transferred along with the toner
> dust. The areas that did not transfer tend be in the areas where I
had
> ripples or bubbles.
>
> For me the biggest problem is all the toner particles that were
> scattered around. I would not have been able to etch a board in that
> condition.
>
> Still I think the technique shows alot of promise. I probably will
not
> do anymore experiments today, but things I would try different is to
> use a scotch tape spacer to try to get the coating thinner and also
> try differnent spreading techniques to try to get the coating more
> even. I also wonder if there is any kind of solvent to thin out the
> thick silicone. That may allow for a more even coating.
>
>
> --- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
> <stefan_trethan@g...> wrote:
> > Hi,
> >
> > had to have a second try.
> > relieved the pressure on the fuser rollers a bit, and made only
one
> run.
> >
> >
> > 1000% the sharpest and best toner transfer i have EVER seen with
NO
>
> > soaking, just peeling of the paper!!!
> >
> > Good, solid, scratch resistant transfer.
> >
> > I might well have come across something here that will make my PCB
> making
> > a lot easier.
> > (Just think about it, no soaking, that means no rubbing an no
> limitation
> > in minimum spacing because there is residue..)
> >
> > Also, the transfer looks very, very sharp to me (must test
further).
> > Maybe the even surface of the silicone is better than rough
paper.
> > (spreading is unknown, but the edges are sharp so it doesn't seem
> much).
> >
> > I'm glad i tried a second time. After the first one was so bad i
> might
> > just have forgotten about it.
> >
> >
> > Well, tests will follow, but i must do something else now.
> > Pleas try yourself too.
> >
> >
> > ST