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Subject: Re: Plated Thru Hole at Home

From: "j_hallows" <j_hallows@...>
Date: 2002-03-07

> First you should worry about how your going to etch.

You read my mine this was my next question.


> If you decide on
> pattern plate then you have choice of tin or tin/lead metal resist.
If you
> choose tin then you must use alkaline ammonia etch. If you choose
tin/lead
> then can use sulfuric/peroxide, ammonium persulfate etch, or
ammonia etch.

Is this the same stuff called Liquid Tin by MG Chemicals and a
similar prodouct by Datak? Or would these get disolved by the etching
solution?

> However, I would be wary on having toxic lead plating solutions
laying
> around. For the ammonia etch it can be chloride or sulfate based. If
> chloride based then you have major waste problems because the
copper cannot
> be recovered easily (at least what I know) and you will need to
treat then
> dump your solution ($$$).

This is like ferric chloride?

If you use sulfate based alkaline ammonia then
> the etchant can be electrolytically regenerated although the
etching rate
> is much slower than chloride.
>
> PCB fabrication may look simple on a flow chart but when it comes to
> actually making it work its a whole different story.
>

Please excuse my ignorance. I have a lot zeal and a lot to learn.