I think it's a volume thing: if you make a certain number of boards, it starts to make sense. I don't make a lot and love my persulphate. I put a teaspoon-and-a-half into fresh water the other night, microwaved it until it was bubbling and the etch was more like 4 mins.
PG
Sent from my phone, anything lewd or incomprehensible is probably autocorrect and not my fault.
----- Reply message -----
From: "Tom Biery" <
judsquare@...>
To: "
Homebrew_PCBs@yahoogroups.com" <
Homebrew_PCBs@yahoogroups.com>
Subject: [Homebrew_PCBs] Re: Using Cupric Chloride
Date: Tue, Sep 27, 2011 11:49 pm
Can someone please tell me why not just use Amonium Persulfate. It seems freely available, that is what I am using and it works fine, I find that if maintained at a temperature of 120 degF the etching is complete in 20 minutes. What am I missing?
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