Homebrew PCBs

I'll do that, but i'm positive the following will be the result:

There will be one temperature where the "shiny thin layer with grey loose  
powder on top" will set in, and another where the solder reflows like  
normal. It seems the first temperature is considerably less than the  
second one, which makes me doubt the partial reflow theory, but i'll try  
and find out the temperatures.

Plumbers reflow it fully, for sure, until the paste melts shiny and then  
you add some solder from a wire. I never felt the need to use those  
expensive pastes for plumbing, a bit of normal plumbing flux and wire  
seems just as good to me.

The first shiny layer at low temperature would appeal for several reasons,  
but then it is surely very thin and much paste is wasted. maybe it could  
be recovered by scraping off and mixing with water.

By the way the paste i have seems mixed with a cleaner, as it foamed up  
when mixed with water and shaken. It hasn't collapsed yet, i emptied the  
bottle leaving only a small amount, added some water, and now the bottle  
is again as full as it was with foamed paste.

I wonder if it might be used for SMD in it's undiluted state, it sure is  
cheap... will try tomorrow...


By the way - has anyone ever tried using a metal "sponge" made of fine  
stranded wire in a soldering iron as "tinning brush"? I think i might try  
to paint over a fluxed board with it.


ST


On Mon, 21 Nov 2005 22:42:47 +0100, Alan King <alan@...> wrote:

>
>
>   Maybe simpler than what I was thinking anyway.  When wiping, you are
>
> taking off the flux and oxides, when it just starts to reflow you are
>
> leaving them on.
>
>
>   Try some test cases and go hotter.  Haven't used this paste, but I
>
> think just in general reflow goes like this, then at a higher temp it
>
> goes shiny on its own.  Maybe you're still not hot enough for full
>
> reflow..  Could be something just a little different with the paste
>
> though, plumbers typically do things a bit differently than how a no
>
> touch reflow goes..  Unless you wipe them with a rag, pipe joints are
>
> often dull right after making them.
>
>
>   Divide and conquer, can't take more than 100 tests to figure it out
>
> exactly!
>
>
> Alan