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¢, 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¢ 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
>
>