Homebrew PCBs

FYI...there is some flux that already has solder particles
in it.  The brand I have in my plumbing supplies is called
"C-Flux", made in the USA by "Rectorseal" of Houston, TX.
http://www.rectorseal.com/C-Flux.php   Note that there
are links to the datasheet.

I purchased a 3-oz jar at a surplus store for 59-cents.  Amazon
has it for over $5!!

The product "cleans and tins" in one operation and is lead-free.
I'm pretty sure there are other brands out there that are
virutally the same thing.  One nice thing about this product
is that it seems to keep "forever".  Just add a little water 
and mix if it starts to dry out.

BTW, the flux in a lot of plumbing products contains forms
of Chloride, an acid.  Be sure to clean ALL of that off the board
to avoid corrosion problems later on.  It is water soluble.

Having said that, I just wonder if this C-Flux stuff could be used
for SMDs?  I.E., in place of the expensive paste that has a shelf
life.  Has anyone ever tried it?

Per the datasheet, avoid breathing in any of the fumes.

Charlie

On Sat, 12 Jan 2013 07:25:51 -0700 "Rick Sparber" <rgsparber@...>
writes:
  
ST,

I failed to mention that I am using plumber's solder paste and paint the
board using an old tooth brush. I tried reflowing the paste with my hot
air
gun but it didn't seem to matter. The brush put it on thin enough. 

The SMD paste contains tiny specs of solder so it is not the same as
plumber's paste. It would be cool if there was a way to take 1/8"
diameter
solder and grind it up into tiny particles. Then it could be mixed with
plumber's paste and used to coat the board. Heat the board in a toaster
oven
and it would be coated. Then wash to remove excess flux.

Rick

-----Original Message-----
From: Homebrew_PCBs@yahoogroups.com
[mailto:Homebrew_PCBs@yahoogroups.com]
On Behalf Of Stefan Trethan
Sent: Saturday, January 12, 2013 7:01 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] No HASL

You can use plumbing solder paste (with flux) and paint the board with
it.,
then you heat the board with hot air or a hotplate..
The paste can be thinned with water to make it easier to apply, and it is
much cheaper than SMD paste.
Excess paste in bare areas and flux just washes off with hot water.

There will be lumps if you apply too much or unevenly, in that case
carefully wipe it off with a paper towel wad while molten.

ST

------------------------------------

Be sure to visit the group home and check for new Links, Files, and
Photos:
http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links




[Non-text portions of this message have been removed]