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Subject: Re: [Homebrew_PCBs] Re: A $500.00 "UV" non-trivial exposure box.....

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2005-11-17

It usually doesn't go wrong once you figured out how to do it, but the
same is the case with TT, i very rarely have a bad transfer.

With my photoboards the resist was discolored faintly after exposure (i
think it was yellowish but not 100% sure). After developing one could see
it quite well, it was kind of smoky transparent.
My main problems were exposure (getting a decent film was impossible with
my laser printer and the papers/transparencies i had. I used this spray
for a while that makes paper translucent, but it was not really good, it
works great as label remover tho.)
Also, i had some old board material that didn't develop very well.
I'm sure i could have gotten it to work eventually, but TT seemed, and is,
so much less work, and this way i can also make component legend and front
panels and stuff (even my a house number sign is a PCB!).

ST


On Thu, 17 Nov 2005 16:55:36 +0100, lcdpublishing
<lcdpublishing@...> wrote:

>
> If you expose a board and the exposure doesn't work out as planed,
>
> it is then ruined isn't it?
>
>
> For example, with toner transfer, if it turns out bad, a missing or
>
> pitted traces or whatever else can go wrong, I wash off the toner
>
> and do it again and again till it is good enough for what I need.
>
> The only loss I have is time and paper.
>
>
> However, from an ignorant point of view ( I have never tried this
>
> process), if something goes wrong, the board can't be used again in
>
> the potoresist process can it?
>
>
> Also, as I don't know what things look like along the way, can you
>
> see the traces with the resist on them after developing? If so,
>
> what does the developed photoresist look like?
>
>
> TIA
>
>
> Chris
>