Wow...
Are you willing to tell us the exact chemicals and times for those
baths?
How do you keep the holes from being eched off along with the
unwanted copper on the boards? Do the holes get plugged somehow?
--
James.
--- In
Homebrew_PCBs@yahoogroups.com, Markus Zingg <homebrew-pcb@...>
wrote:
>
> I'm right now through plating a board, and quickly took a picture
for
> you. The board is now in the last step, the copper plating bath.
>
> The station you see on the picture was built by myself. It's the
second
> generation, and I intend to put a website online about several
processes
> around making even multilayer boards at home with home built
equipement.
> I just did not had the time yet to upload and document everything.
The
> old page I once had online is gone due to me changing providers.
>
> You basically need a laminator and laminate (since you must tent
the
> through plated holes cause you have to make them bevore you etch
the
> artwork). You also need a through plating station. I use one with
five
> baths. It's acutally not all that complicated, and does also not
have to
> be expensive, but you must be prepared for initial costs of ~$1000
if
> you have nothing. I mean you need copper anodes (coper is expensive
> these days), a relatively simple electronic cirquit, some motors,
some
> heaters, a lot of plastic sheets, a big plastic box and a lot of
time
> and ideas :-). I intend to sell stations once said page is up but
also
> publish plans for those who want to build one on their own. The
selling
> part is more thought as a help for those who don't want to spend
the
> time on building one themselves or those who want to take profit
from
> the experience made here.
>
> The plating process can be done differently. I use an aproach as
it's
> also used in the industry. The advanteage of this is that you get
very
> consistant beautiful absolutely repeteable results. The
disadvantage is
> that you have to buy the chemistry. It's however relatively easy to
buy
> and if you buy it at the right place not at all that expensive.
>
> Anyways, I use five baths. The process I use in the order applied
follows:
>
> - The first bath micro etches the FR4 material (and of course also
a
> little the copper but thats a side effect). The purpose of this is
to
> assure that the palladium emulsion which is applied in the fourth
bath
> (see below) can stick to the FR4 makeing it conductive to the
degree
> needed for the effective plating process. You have to rinse the PCB
with
> water after this step.
>
> - The second bath is a so called predip. It's a sodium cloride
solution
> with aditives and the same as the third bath, but there is no
palladium
> emusion in it. The purpose of this bath is to aclimate the PCB to
the
> following bath and thereby avoiding contamination of the third,
bath
> which is a bit critical and contains the most expensive chemistry
(the
> palladium emusion). There is therfore NO rinsing after this step.
>
> - The third bath is the one makeing the holes conductive for the
> subsequent plating process. It's the same as above, but contains
the
> palladium emulsion. The emusion is somewhat expensive, but to give
you
> an idea, half a litter costs ~80$, and said half litter will last
you
> for the next ten years with a station of the size of the one I
build, so
> costs are relative. You must rinse the PCB after this step.
>
> - The fourth bath is hardening the palladium. This is having the
effect
> that it sticks better to the FR4, but splitters of from the copper.
Also
> rinse after this step.
>
> - The fifth bath is the effective copper plating. The attached
picture
> (don't know if this works with this group, if I see that the
picture is
> not attached, I will upload it to the files secion and post in a
second
> mail where it is) showes the board in this bath. You apply ~2.5
amps per
> square decimeter of copper material to this bath and run the PCB in
> there acording to the thikness of copper you want to end up with.
After
> this the plating is done. What's left is to trughly rinse the PCB,
and
> then of course continue with laminating dryfilm resist, expose and
etch
> the outher layers (or only layers in case of a double sided board).
>
> On the picture you see that you need several tanks and a mechanical
> construction to swing the PCB back and forth.
>
>
> HTH
>
> Markus
> pic of throughplating station
>
>
>
> peripherin schrieb:
> >
> > Now I am going to ask a question that I have tryed at before and
> > failed.
> > Does anybody know how to thru hole plate useing home equipment ?
Also
> > any good websites would be welcome ?
> >
>
>
>
> [Non-text portions of this message have been removed]
>