I get a quart of acetone for like $2.50 from home depot so its a
truely minimal expense. I think its even cheaper in gal quantities.
I've used maybe 1/4 of it and washed about 20 boards. So it costs
litterally pennies per washing. I just use a thin dribble on the
board and scrub with an old toothbrush. voila! clean and ready to
scrub for the next test run.
I'm really beginning to appreciate how much variability paper imparts
to the process.
Alan, I hear your point on the difficulty of getting pressure right
but I'm even more convinced that its the critical factor. Laminators
will give even pressure so that's a good reason to get one. maybe
I'll break down and buy one...
By the way, are people preheating their boards? I put them in the
oven at 250 F to dry them out and then go straight to the transfer
stage.
--- In
Homebrew_PCBs@yahoogroups.com, Stefan Trethan
<stefan_trethan@g...> wrote:
>
> > And LOL yes acetone is magic stuff. Try using a plastic pad
and
> > alcohol to
> > clean the toner from a board if you haven't already, it'll give
you a
> > whole new
> > level of appreciation for what a joy acetone is to use. Acetone
> > converts what
> > seems like hours into just seconds, who knew it was a time
machine
> > component?
> >
> > Alan
> >
>
> If you really think so...
>
> a) it is absorbed through the skin (even through some gloves) and
poisonous
> b) it evaporates very quickly
> c) it attacks plastic
> d) it evaporates out of the closed can (the can it was sold in !!!)
> e) it is not too cheap
> f) we have seen at least one case where the acetone attacked the
epoxy
> and the toner rubbed in smearing it all over.
>
> I use simple laquer thinner.
> not quite as fast with evaporation, much cheaper, maybe as toxic, i
dunno
> (but the warnings
> are less).
> it still attacks plastic (take alcohol if you need to prevent that -
but
> remember the toner is plastic).
>
> it has never attacked the epoxy so far.
>
>
> I liked acetone very much too in the past.
> but now my opinion is different - at that price it simply is not
> allowed to evaporate out of a properly closed tin.
>
>
> alcohol is no good in rubbing off toner - because it doesn't attack
> plastic.
> i tried it - it was close to rubbing with water.
>
> really do try paint thinner, it is working ok....
>
>
> another hint:
> i scrape off my toner with a flat edge.
> like when the board doesn't work out right after fusing you can
scrape it
> off all at once.
>
> I only scrape it off a completed board if the traces are not too
thin, but
> with 0.5mm it hasn't
> taken the trace with it.
>
> this is much quicker than all the rubbing (but you might need a
light
> sweep over it if you miss
> some tiny bits with scraping)
>
> just another opinion...
>
> ST