Homebrew PCBs

This subject seems to come up every now and then.

I wonder if anybody has come up with information about how to metalize 
inside the via holes?

I am not a chemist so please keep any information suitable for a dummy.

I have tried silver paint but it is too viscous and it would need some 
suction or pressure to give a smooth surface. Also it is most 
important to me to be able to be left with a suitable hole for IC pins.

My hobby is RF electronics and I need to use squillions of vias for RF 
ground connections. Some as small as 12 mil.

Any solutions (pun intended) for that problem that don't involve 
buying gallons of the stuff and don't require a bank loan would be 
most useful to me.
Frank VK4BLF (QTHR)

the way to do it is to drill the holes first, you will then have to etch the sides of the hole (dont remember excactly what was used for it) then you put the board into a electroplating path and deposit copper, once youre done you apply photoresist put your pattern on the board the resist will have to cover the holes though, you etch the board an strip and and there you have it !

frankwinter1 <frankwinter1@...> wrote:          This subject seems to come up every now and then.

I wonder if anybody has come up with information about how to metalize 
inside the via holes?

I am not a chemist so please keep any information suitable for a dummy.

I have tried silver paint but it is too viscous and it would need some 
suction or pressure to give a smooth surface. Also it is most 
important to me to be able to be left with a suitable hole for IC pins.

My hobby is RF electronics and I need to use squillions of vias for RF 
ground connections. Some as small as 12 mil.

Any solutions (pun intended) for that problem that don't involve 
buying gallons of the stuff and don't require a bank loan would be 
most useful to me.
Frank VK4BLF (QTHR)



                           

       

[Non-text portions of this message have been removed]

I would like to try doing through hole plating, but I am not at a
point where I  really need it. However, if I were to get something
right now I would probably go with the copper plating kit offered by
Caswell Plating. They offer a 1.5 gallon kit for $169. Of course
depending on how much you want to spend, that may be considered too much.

--- In Homebrew_PCBs@yahoogroups.com, "frankwinter1"
<frankwinter1@...> wrote:

>
> This subject seems to come up every now and then.
> 
> I wonder if anybody has come up with information about how to metalize 
> inside the via holes?
> 
> I am not a chemist so please keep any information suitable for a dummy.
> 
> I have tried silver paint but it is too viscous and it would need some 
> suction or pressure to give a smooth surface. Also it is most 
> important to me to be able to be left with a suitable hole for IC pins.
> 
> My hobby is RF electronics and I need to use squillions of vias for RF 
> ground connections. Some as small as 12 mil.
> 
> Any solutions (pun intended) for that problem that don't involve 
> buying gallons of the stuff and don't require a bank loan would be 
> most useful to me.
> Frank VK4BLF (QTHR)
>

Apart from Adam, how seems to understand A LOT about chemistry, I'm not 
aware of anybody who has developped his/her own chemistry which he could 
SUCESSFULLY use. Alas, don't loose time on this part except chemistry is 
sort of your hobby.

I simply BUY the chemistry. It's not that expensive in the long run. You 
must buy some stuff in certain minimum quantities (which varies from 
supplier to supplier) but in the end you have a professional product, 
leading to repeatable reliable quality results.

I'm often amused when reading certain forums where people got to lenghty 
excursions to get metallisation to work. If they would only spend a 
tenth of the time and money on the right chemistry they would be up to 
speed in a snap....

The easiest way IMHO is to get in touch with a boardhouse. You may have 
to visit them and talk to the people there to get to results, and if it 
even were for watching how they do it (which gives a lot of 
information). Usually these people are more than happy to help out with 
small quantities for hobbyist use (if they realize that there is no 
competition ariseing out of this).

Just my 2\ufffd of course.

Markus

javaguy11111 schrieb:

>
> I would like to try doing through hole plating, but I am not at a
> point where I really need it. However, if I were to get something
> right now I would probably go with the copper plating kit offered by
> Caswell Plating. They offer a 1.5 gallon kit for $169. Of course
> depending on how much you want to spend, that may be considered too much.
>
> --- In Homebrew_PCBs@yahoogroups.com 
> <mailto:Homebrew_PCBs%40yahoogroups.com>, "frankwinter1"
> <frankwinter1@...> wrote:
> >
> > This subject seems to come up every now and then.
> >
> > I wonder if anybody has come up with information about how to metalize
> > inside the via holes?
> >
> > I am not a chemist so please keep any information suitable for a dummy.
> >
> > I have tried silver paint but it is too viscous and it would need some
> > suction or pressure to give a smooth surface. Also it is most
> > important to me to be able to be left with a suitable hole for IC pins.
> >
> > My hobby is RF electronics and I need to use squillions of vias for RF
> > ground connections. Some as small as 12 mil.
> >
> > Any solutions (pun intended) for that problem that don't involve
> > buying gallons of the stuff and don't require a bank loan would be
> > most useful to me.
> > Frank VK4BLF (QTHR)
> >
>
>

frankwinter1 wrote:
> This subject seems to come up every now and then.
> 
> I wonder if anybody has come up with information about how to metalize 
> inside the via holes?
> 
> I am not a chemist so please keep any information suitable for a dummy.
> 
> I have tried silver paint but it is too viscous and it would need some 
> suction or pressure to give a smooth surface. Also it is most 
> important to me to be able to be left with a suitable hole for IC pins.
> 
> My hobby is RF electronics and I need to use squillions of vias for RF 
> ground connections. Some as small as 12 mil.
> 
> Any solutions (pun intended) for that problem that don't involve 
> buying gallons of the stuff and don't require a bank loan would be 
> most useful to me.
> Frank VK4BLF (QTHR)
> 
> 


You have to realise that the copper electroplating step is only one of 
many stages to fabricate a PTH PCB. Each of the stages, dry film 
laminations, making holes conductive (or "activated" for subsequent 
electroplating) and electroplating have their own problems. All require 
a lot of learning and you will make many a dud PCB before gaining 
confidence.
In short your best to follow Markus's advice and purchase the necessary 
chemistry. Even so there is a lot to know about tank construction and 
what to do when the chemistry mysteriously stops working.

Adam

----- Original Message ----- 

From: "Markus Zingg" <homebrew-pcb@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Tuesday, May 27, 2008 7:53 AM
Subject: Re: [Homebrew_PCBs] Re: Via Through plating


> Apart from Adam, how seems to understand A LOT about chemistry, I'm not
> aware of anybody who has developped his/her own chemistry which he could
> SUCESSFULLY use. Alas, don't loose time on this part except chemistry is
> sort of your hobby.

Mega Electronics sells complete kits:

http://www.megauk.com/through_hole_plating.php

They are too expensive for home use (\ufffd4765 GBP), but they sell the chemicals 
separately - \ufffd350 GBP for a starter kit. The web page describes the process, 
it seems quite straightforward with their chemistry.

Leon
--
Leon Heller
Amateur radio call-sign  G1HSM
Yaesu FT-817ND transceiver
Suzuki SV1000S motorcycle
leon355@...
http://www.geocities.com/leon_heller

From their description, the chemistry looks like it's 100% what I use 
here. However, the price for the chemistry seems a bit steep. It depends 
though on how much of each part needed it includes. One must know that - 
IF TREATED CORRECTLY - the chemistry can be used for multiple years. It 
thus depends on how many board one makes, how complex they have to be etc.

Since my designs almost always require multiple layers I don't have that 
much choice, so for me the 350 GBP would not hinder me if I were in the 
position of haveing this as the only source. I can only repeat that 
getting in touch with a board house is the best one can do. Usually 
there is more than one such house around so if it really should be that 
one is not sucessful at one place it might be at another.

Building a plating line is feasable, and for my use, the one on that 
site would be way too big anyways. It should be noted that the better 
the size of the tanks reflect the requirements board size wise, the 
fewer chemistry one needs to set up and alas such a starter kit for a 
bigger line may easily be used to set up a smaller line 5 times or more. 
I.e. I personally use 2.2l tanks for the first four baths, and a 4.4l 
tank for the effective plating bath. That's mostly due to the space 
requiered for the copper anodes.

HTH

Markus

Leon schrieb:

>
> ----- Original Message -----
> From: "Markus Zingg" <homebrew-pcb@... 
> <mailto:homebrew-pcb%40shdesign.info>>
> To: <Homebrew_PCBs@yahoogroups.com 
> <mailto:Homebrew_PCBs%40yahoogroups.com>>
> Sent: Tuesday, May 27, 2008 7:53 AM
> Subject: Re: [Homebrew_PCBs] Re: Via Through plating
>
> > Apart from Adam, how seems to understand A LOT about chemistry, I'm not
> > aware of anybody who has developped his/her own chemistry which he could
> > SUCESSFULLY use. Alas, don't loose time on this part except chemistry is
> > sort of your hobby.
>
> Mega Electronics sells complete kits:
>
> http://www.megauk.com/through_hole_plating.php 
> <http://www.megauk.com/through_hole_plating.php>
>
> They are too expensive for home use (\ufffd4765 GBP), but they sell the 
> chemicals
> separately - \ufffd350 GBP for a starter kit. The web page describes the 
> process,
> it seems quite straightforward with their chemistry.
>
> Leon
> --
> Leon Heller
> Amateur radio call-sign G1HSM
> Yaesu FT-817ND transceiver
> Suzuki SV1000S motorcycle
> leon355@... <mailto:leon355%40btinternet.com>
> http://www.geocities.com/leon_heller 
> <http://www.geocities.com/leon_heller>
>
>

>>> Frank wrote:
>>> I wonder if anybody has come up with
>>> information about how to metalize
>>> inside the via holes?

>>

> Markus Zingg wrote:
>
> <SNIP>
> The easiest way IMHO is to get in touch
> with a boardhouse. You may have to visit
> them and talk to the people there to get
> to results, and if it even were for
> watching how they do it (which gives a
> lot of information). Usually these people
> are more than happy to help out with 
> small quantities for hobbyist use (if
> they realize that there is no competition
> ariseing out of this).

Seeing as the original poster signed off
VK4xxx it means his "local" board house is
in Brendale (and local has a different
meaning out here.  Brendale could in fact
be a 2 day drive and still be his closest
PCB manufacturer).

At any rate our local place is far from
helpful.

Maybe if there are enough of us on here
we can do a bulk order from OS to actually
get hold of things.

Markus - since you are the most experienced on THP. Tell us did you
tried conductive metal holewall activation  ? 
http://www.thinktink.com/stack/volumes/volvi/condink.htm

Also I have seen a nice tutorial how to copper plate nonconductive
materials : 
http://www.instructables.com/id/Electroforming-an-Iris-Seed-Pod/

What do you think about it ?

Regards,
Daniel

That leads me to a thought... Can a CuCl etchant bath be used for
electroplating?