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Subject: Re: [Homebrew_PCBs] smd solder paste thinning

From: Stefan Trethan <stefan_trethan@...>
Date: 2004-06-10

>
> Mix 7 parts glycerine to 3 parts isopropyl alcohol
> Sometimes, depending on the paste the alcohol content
> must be even lower than 3 parts. Thin the paste ONLY
> as thin as you need it and no more. Also, this mixture
> works wonders as a flux to keep solder from bridging
> between pins on smd and through hole componets.
> Although, the correct tip is everything when doing
> smd. You can also put some of this on solder braid and
> solder will literally jump of whatever that it's stuck
> to.
>
>
>
> Regards
>
> Marvin Dickens

well, was shopping.

Bought some glycerine and IPA.
Found it at the chem. shop and was again positive surprised that it cost a
third
of what it would cost mail order (and they refill the bottles so it it
even cheaper).
I also got a liter of Acetone when i was there, i really hope the PE
bottle is up to it...

But back on topic:

the glycerine is really thin, like a thin oil.
I do not think it will be required to thin it further with IPA.
What do you think, should i try it with glycerine only or does the IPA
serve another
purpose too?

thanks

ST

P.S.: I found that bicycle valves make GREAT nozzles for bottles with
solvents.
the caps are airtight on this valves. I use the old type which used a
hose, snip off the
valve part so it is open both ways. (basically you end up with a threaded
pipe).
then i drill a hole in the plastic lid of the bottle and glue the valve in.
the plastic bicycle cap is used to close this new outlet.
Really much more practical than the 2-cm opening, if you press a rag
against it to dampen
it you will contaminate the whole bottle of solvent over time (and use
much more
than you really need. with the new tiny nozzle
you can dispense a few drops directly where you need it with no
contamination.
Use a glue that is compatible to the chemical (i used hot glue).
Of course the valve is metal so don't try it with acids, or H2O2 etc...

There is a special lid with a nozzle & cap for this type of bottles, but i
don't
have it and i'm not sure how tight the snap on cap really is.