Homebrew PCBs

Well, after much research and discussion, I've found how these 
machines really work. Apparently, the bottom roller is a steel(or 
covered) roller that is partially submerged in a solder bath. What 
prevents the solder from building up on the steel roller is the 
addition of Solder Salts that help to coat a thin layer of solder on 
the roller. Then the top roller is usually made of silicon rubber and 
the more pressure placed between the two rollers, the thinner the 
layer of solder on the pc board. Of course, the cost of this machine 
should be minimal seeing as how the main cost of use is the salts and 
the replenishment of solder. The ability to acquire cheap salts is 
the daunting task; anyone have any ideas on that? I think that the 
machine can be homebrewed and be cheaper then TiNNiT and lasts longer 
as well.

On Thu, 04 Mar 2004 08:38:21 -0000, gmanca101 <gmanca101@...> wrote:

> Well, after much research and discussion, I've found how these
> machines really work. Apparently, the bottom roller is a steel(or
> covered) roller that is partially submerged in a solder bath. What
> prevents the solder from building up on the steel roller is the
> addition of Solder Salts that help to coat a thin layer of solder on
> the roller. Then the top roller is usually made of silicon rubber and
> the more pressure placed between the two rollers, the thinner the
> layer of solder on the pc board. Of course, the cost of this machine
> should be minimal seeing as how the main cost of use is the salts and
> the replenishment of solder. The ability to acquire cheap salts is
> the daunting task; anyone have any ideas on that? I think that the
> machine can be homebrewed and be cheaper then TiNNiT and lasts longer
> as well.
>
>

OK, you build one and then i copy it ;-)

But i simply have no space for such a giant machine like it was showed in 
the pictures,
it must be small....

It would be practical to have it, but i do not know when time allows to 
even think
about building one.

ST

gmanca101 wrote:
> the replenishment of solder. The ability to acquire cheap salts is 
> the daunting task; anyone have any ideas on that? I think that the 
> machine can be homebrewed and be cheaper then TiNNiT and lasts longer 
> as well. 
> 

   Not sure about the more modern stuff, but plenty of older printers etc had a 
solid steel core for the platen.  Strip the rubber off and one may work fine, 
and another with the rubber for the top roller.

   May be quite useable if everything is very cheap.  If not then only those 
with med/high quantity of boards could justify it, it'll represent 10 years 
worth of Tinnit for many if there's much cost to it.

   And if they're not particularly special, the salts can be found after the 
fact for cheap.  Hunt down a bulk supplier and they shouldn't be too big an 
issue, finding them may take some time though.  $2-$3 a pound for bulk and no 
doubt solder will be cheaper, and it doesn't go bad very fast either.

   There are also many methods to deal with solder, like a thin layer of oil on 
top to keep it from oxidizing etc.  With a little experimentation there may be 
ways other than the salts that are more cost/ease effective for home use.

   Also there is always the frying pan dip soldering, it works well enough for 
soldering components and should really do well enough for most people's solder 
plating too for low quantities.  A friend has a commercial machine built around 
the same basic principle, it works very well for both uses.

Alan

>
>    Not sure about the more modern stuff, but plenty of older printers 
> etc had a
> solid steel core for the platen.  Strip the rubber off and one may work 
> fine,
> and another with the rubber for the top roller.

I think you will need heat resistant rubber, like in a laser printer fuser.
but this may still be not enough, maybe one can mold it with heat resistant
silicone.


>    Also there is always the frying pan dip soldering, it works well 
> enough for
> soldering components and should really do well enough for most people's 
> solder
> plating too for low quantities.  A friend has a commercial machine built 
> around
> the same basic principle, it works very well for both uses.


I wonder if there is not too much tin built up on the tracks.
more description please.

ST

>
> Alan
>