Homebrew PCBs

Dave,

The pictures (and description) in the link you gave made the impression 
to me that the tank is molded as one piece. If now - acording to the 
experience others obviousely have made this turns out not to be true - 
you are IMHO right that its similar to doing your own then. If you also 
get the air pump heater etc. for just $49 I still think it's a very good 
offer but hearing that the tank is not made of one single piece is a 
bummer....

Anyways, I do my tanks using polystyrene glass sheets that I cut into 
the shape I need using a fine circular table saw and "glue" them 
together. I use Methylenchloride as the glue and this chemically welds 
the parts together. So this is not really the same as glueing in the 
traditional sense. In fact, the this way chemically welded parts are so 
strong that if you mechanically try to break such an area, it usually 
breaks elsewhere. The key here is that if you cut the sheets into shape 
you use a fine saw so as the areas which are glued together are even 
with no unregularities or such. The nice part about the polystyrene 
glass is that you can see the "glued" area all through the material like 
if you would X-ray it if it were a different material and as such you 
can optically check if it will hold forever or if there are areas where 
it did not worked out well.

Obviousely, for a pure etching tank, using a redy made available 
container is not wrong. I must admitt that the tanks I do are for the 
trough plating station where space is  constrained and where bigger 
tanks mean spending partially lots of money more for pricey chemistry 
just because the tank is not optimally sized. For the first incarnation 
of the tanks about four years ago, I welded the plastic using a hot air 
gun because I too was afraid of leakage back then. Now with the 
experience of using Methylenchloride I definately don't want to go back 
to this hassle.

Btw, I always fill the tanks of my machines only for relatively short 
periodes of time. I don't care leaving the fluids in there for a couple 
of weeks if I'm in a phase where I do a couple of PCBs in a row but once 
this phase is over, I always fill the fluids back into containers that 
can be air sealed and which are made of one piece of plastics (Sorry, 
don't know the propper term for them cause english is not my native 
language, but I hope you know what I mean). I do so to avoid loss of the 
partially pricey stuff (it otherwise vaporizes over time) and also for 
security reasons. There are cheap (about 1$ a piece) hand pumps 
available in flower/gardening stores which are excellent tools to fill 
such fluids back and forth withouth ever spoiling a single drop.

Markus

Dave schrieb:
>
>
> Markus Zingg wrote:
> >
> > Dave,
> >
> > Just my 2\ufffd, but that web-tronics offer seems fairly good to me. Not only
> > is it a molded tank (and as such definately never leaking), but made for
> > the purpose including hangers pump etc. I mean, even if you put your own
> > etching system together, you are likely to spend a similar amout of
> > money let alone the time you need to get the different parts etc.
> >
> > The reason I see why one makes his own tank could be lead and delivery
> > time to get said tank though :-) I also made my own tanks over time, but
> > I must say I'm really impressed by this offer.
> >
> > Again, just my 2\ufffd here....
> >
> > Markus
>
> Markus,
> If they lasted without leaking (as someone else noted) then it would
> be a great deal. If they end up leaking, or the possibility is there,
> then I may as well just make one. Besides, thats part of the fun. I will
> get to scheme up a mechanical agitator. :)
> Thanks,
> Dave
>
>