I intensely researched the chemical options, and in the US
For small scale, inking the holes is the most cost effective, and cleanest
method. ie.. if you cant afford the ink you definitely cant afford the
chems, and testing, and wetbench, ventilation, filtering, and effluent
processing. of desmear, carbon black. and associated neutralizers.
$75 for roughly 12500 holes <50Grams>, That's $0.006 per hole
BTW You can reuse the excess ink that you remove if you are very careful and
use a recovery jar in your vacuum line If it's getting to hard, I glob it on
the board, and put a few drops of acetone on it, and quickly smear it in. so
far it's worked perfectly.
The EPA has a great breakdown with enough info to point you toward the
makers of the chems
Also discusses all available techniques.
Conductive ink is listed as "currently in development" <g>
http://www.epa.gov/dfe/pubs/pwb/tech_rep/ctech/index.htmAs for PVC Cement and Acrylic glue, neither are really glue, they are both
fusers, that chemically melt the edges in contact and fuse them together --
never to be undone. I've built a number of saltwater filter boxes with clear
acrylic using the "glue" in a syringe just applying it into the joint, and I
have some that are 12years old, no problem. However saltwater is not
acid...I know that PP, HDPE, and PVC all come before Acrylic or anysort of
ABS for longterm chemical and temperature resistance
JT
----- Original Message -----
From: "ballendo" <ballendo@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Sunday, March 14, 2004 6:53 PM
Subject: [Homebrew_PCBs] THP line questions was Re: Welding PVC - OT
> Adam, Markus Z,
>
> Will pvc (cemented) stand up to the chemicals of your THP system?
> What about glued acrylic?
>
> Next, Has anyone found a good US supplier of the "commercial" THP
> chemicals, like the Bungard chemistry Markus uses? Is Bungard sold in
> the USA?
>
> I don't want to mess with the black hole techniques, or vacuuming
> away the expensive hole wall activator...
>
> Thank you in advance,
>
> Ballendo
>
>
>
> --- In Homebrew_PCBs@yahoogroups.com, Adam Seychell
> <adam_seychell@y...> wrote:
> You are correct saying that if something can
> > be glued then its should be glued and not welded because its
> > simpler. PVC pipe fittings is an example of glued plastic.
> > Sometimes a the flat face of a PVC block or sheet can be glued to
> > another.
> >
>
>
>
>
>
> Be sure to visit the group home and check for new Bookmarks and files:
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>
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>
>
>