Homebrew PCBs

Patrick,

Your input is highly apreciated. However, I made the experience that 
wiht the very small tanks I use (remember, 4 liters for the copper 
solution, 2 for the others) it turned out that some shortcuts are possible.

#1 I tried air agitation. It did NOT change ANYTHING to better or to 
worse. So one really can savely omitt this.

#2 I can run the copper solution at 2.5 t 3 amperes per Dm2 of  visible 
copper. Since you mention dry film resist, you must obviousely use a 
different aproach (care to explain it to us?) than I do cause at the 
time I thru plate, I have no laminate on the PCB. The laminate is 
applied there after. That way, I can reduce the time in this bath to 20 
- 25minutes. Not that I usually care that much though, but I made 
experiments with less amp\ufffdres and again, it did not changed the quality. 
Of course, if I go really to 3+ amps what you describe starts to happen 
(mat surface, small nails on the borders etc.).

#3 the anode bags (polypropylene) is not THAT important for me cause I 
always empty the tanks after use and every now and then filter the tank 
contents while doing so. I fully agree that they are "nice to have" 
cause they probably could omitt the filtering but it's really easy to do 
so while emptying the tanks versus getting bags that fit the size of the 
home made anodes seems difficult.

All other statements you made are also along my experience. Again, I 
think above differences have to do with the very much smaller tanks I 
use versus your setup - right?

Markus


tsescrl schrieb:
>
> Hello,
>
> For Anodes copper, very necesary use "PHOSPHORIC COPPER"
>
> For me, after 20 year using electrolitic copper bath, is no heating,
> to min 15\ufffd centigrade.
>
> Attention for the surface of the anodes, anodic surface is maximum,
> but very very maximum 1/2 the surface of the plate per faces.
>
> Normaly, use 1.6 Amps per Dm2 of visible copper surface, not the
> print surface, but only the copper you see after insolation and
> develop dry film is so little wat you think.
>
> Use also 40 minutes electrolitic immersion time and you obtain a good
> result, normaly, 17.5 microns d\ufffdposition.
>
> The d\ufffdposition is glossy, if you obtain a mat surface, you are higt
> for the amp\ufffdrage.
>
> In first time, with a new bath, attention with the brigtner, not add
> bigger, is necessary a long time before add replenisher brigtner.
>
> For brigtner, you add replenisher if you see the external coin are
> mat.
>
> For a new bath, use a brush plate, just a double face plate, no dry
> film, put on the bath, and use 0.2 Amp per dm2 to 2 hours, your bath
> is started, all the impurity is go, and important, your anodes is
> flashed, normaly hi come black.
>
> After 2 our, your plate is very glossy.
>
> Also important, put your anodes in a polypropilene sac, al the
> impurity go not in bath.
>
> Very important, if you d'ont use the bath for a long time, put out
> the anode, and look for the watter \ufffdvaporation, adjust only with
> demin\ufffdralised watter, only, no chemestery.
>
> For anode, you can obtain to "AMPERE" in France, very nice mat\ufffdrial,
> also for tin or tin-lead anode.
>
> For electrolityc bath, normaly is also a pump and a filter to make
> recirculation.
>
> Is also very important you have pressure air with a ramp in the
> bottom off the tank with small drilling holle, the air go to the top
> off the bath, just a little pressure
>
> Put this ramp just at the bottom of the plate.
>
> Good ammusement, best regards, and d'ont h\ufffdsitate to ask me.
>
> Pleasure
>
> Patrick Belgium Europe
>
> --- In Homebrew_PCBs@yahoogroups.com 
> <mailto:Homebrew_PCBs%40yahoogroups.com>, Markus Zingg <homebrew-pcb@...>
> wrote:
> >
> > Hi Suske,
> >
> > I obviousely don't care too much from where you get the chemistry
> as
> > long as it hopefully works out well for you :-). In other words, I
> > apreciate the service Bungard is providing and as such wish them a
> > looong life. Apart from this I'm not related to them in any ways. :-
> )
> >
> > For the heaters, I use just dirt cheap regular aquarim heaters. The
> only
> > thing to watch out here is that they usually don't go up to the
> > temperature you need. However, they are (usually, check with what's
> > available at your place) built using bimetal switches to switch the
> > power on and off. The ones I found here (really the very cheapest
> ones,
> > I use 100W heaters) have inside a little plastic part that sits on
> a
> > fine threaded screw which is what you turn from outside to set the
> > temperature. That plastic part is having a nose to limit
> the "hottest"
> > end position. By simply cutting of that nose you can modify the
> heaters
> > so as they go up to the requiered 75 degree celsius. There is
> usually no
> > problem or security issue involved here apart from the obivous
> safety
> > handling of such heaters. The heaters are made for such
> temperatures.
> > Those for the aquarium are just limitted so as the average aquarium
> user
> > does not end up unintentionally boiling the fishes.... :-) Just
> make
> > sure you never turn the heaters on if they are not COMPLETELY
> flodded in
> > the fluid or else the surrounding glass will instantly break.
> >
> > As far as the anodes go I think the phosphor is important to get
> good
> > results. I bougth my material from a source here in Switzerland
> > (Haeuselmann Metalle) which is carrying different alloys of copper.
> One
> > of them is having a small percentage of phosphor in it. So you may
> shop
> > around a little up until you find such a source. If you have found
> an
> > alternative source for the chemistry - why not ask them for a
> pointer to
> > annodes? Professionals use copper nuggets in titanium containers
> which
> > are then flodded in the copper solution and at least those must be
> > available near you if there are also board houses since this is
> what
> > they use. As a last straw, you could use such nuggets, melt them
> and
> > found anodes this way. I of course also could buy you the raw
> material
> > here at the 1:1 costs of what I pay. However, shipping the ~2KG of
> > material might be a bit costly but feel free to get back to me if
> that's
> > what you want.
> >
> > HTH
> >
> > Markus
> >
> > _bojan_ schrieb:
> > >
> > > Hi Markus,
> > >
> > > Thanks a lot for your writing.
> > >
> > > Another detail ar fluid heating. Bungard use PTFE plated large
> area
> > > heaters. What did you use for fluids heating in tanks?
> > >
> > > What about anodes, can I use some copper plate or I must use that
> > > sulphurised copper.
> > >
> > > B.T.W. I am on the way to get my chemicals but not from
> Bungard. ;)
> > >
> > > Best regards,
> > >
> > > Suske
> > >
> > >
> >
>
>