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Thread ID: 115339 2011-01-14 03:02:00 Want to make PCB etchant.. where to buy? Agent_24 (57) PC World Chat
Post ID Timestamp Content User
1169628 2011-01-14 03:02:00 I usually use Ferric Chloride but my supplies are starting to run out. Also, it's expensive and harder to get now.

Then, I found this: www.instructables.com

Is anyone already using this method and knows where to get the required chemicals? (Muriatic Acid and Hydrogen Peroxide) Or doesn't use it and knows anyway?
Agent_24 (57)
1169629 2011-01-14 03:49:00 Hydrochloric Acid (HCl), is also known as Muriatic Acid or spirits of salts and should come from a hardware store, Hydogen Peroxide (H2O2) is used for bleaching hair etc, and should be available from a pharmacy, although I don't know what strengths you need. Brucem (8688)
1169630 2011-01-14 03:51:00 The person who wrote that instructable says for the Hydrochloric Acid they used 31.45% and for the Hydrogen Peroxide it was 3% Agent_24 (57)
1169631 2011-01-14 04:00:00 Etchant like ammonium persulphate would be very much better than hydrochloric acid or Hydrogen Peroxide.
I am very dubious about hydrogen peroxide, doubt it would be strong enough unless you could get rocket grade test peroxide ! :)

DSE use to sell both persulphate and ferric chloride before they became toaster shops, but they were expensive.

I found these sites via Google:

www.surplustronics.co.nz

www.voltelectronics.co.nz

I got a big jar of ferric chloride powder from a pcb manufacturer quite a while ago now. You could try and find a firm that makes boards and see if they will let you have some.
Terry Porritt (14)
1169632 2011-01-14 04:17:00 I am hesitant to use Ammonium Persulphate as this article ( . com . au/index . php?id=article&name=etchantComparison" target="_blank">ultrakeet . com . au) shows the resulting board being a lot worse quality-wise than when using Ferric Chloride (and in my own experience, Ferric Chloride works very well)

I am not worried about the strength of the HCl\H2O2 etchant being too low, it looks like a lot of people are using it very well .


If this is the first time you're using this batch of solution (and I presume it is), it'll etch super-fast . This small board took only 2 minutes . Yikes!

I also like the way you don't have to throw it away at all, so it should be cheaper in the long run . . .


Also, note how the etchant gets greener over time as it eats away the copper . This is good news .

What's happening is that you're dissolving the copper from the board and turning it into cupric chloride . In the long-run, the cupric chloride will be doing most of the etching (instead of requiring disposal) . For now, just watch your solution turn light green . Next time you use it, the color will deepen .
Agent_24 (57)
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