Homebrew PCBs

I used it for a short time.  I loved that I could see the etch process 
through the solution.  I think I stopped because I couldn't get it any more.

On 3/21/2016 4:35 PM, 'keith printy' keethpr@... 
[Homebrew_PCBs] wrote:
>
> Anyone here besides me ever use ammonium persulfate? When I worked in 
> an electronics plan that was what we used to etch our boards. We would 
> put it in a corningware baking pan and put it on a small hotplate to 
> keep it warm. It was fairly quick depending on what concentration you 
> used . it is an oxidixer ,mix with sugar and heat it goes boom!
>
> *From:*Homebrew_PCBs@yahoogroups.com 
> [mailto:Homebrew_PCBs@yahoogroups.com]
> *Sent:* Sunday, March 20, 2016 2:53 PM
> *To:* Homebrew_PCBs@yahoogroups.com
> *Subject:* RE: [Homebrew_PCBs] Re: Mark-8 'Non-plated through holes' 
> and 2 sided PCBs
>
> Where is nitric acid found?  Is it practical compared to HCl/H202 or FeCl?
>
> *From:*Homebrew_PCBs@yahoogroups.com 
> <mailto:Homebrew_PCBs@yahoogroups.com> 
> [mailto:Homebrew_PCBs@yahoogroups.com]
> *Sent:* Sunday, March 20, 2016 2:26 PM
> *To:* Homebrew_PCBs@yahoogroups.com <mailto:Homebrew_PCBs@yahoogroups.com>
> *Subject:* [Homebrew_PCBs] Re: Mark-8 'Non-plated through holes' and 2 
> sided PCBs
>
> I do RF PCBs requiring micro strips etc. It must use double sided FR4 
> boards with consistent permittivity and very accurate trace 
> thicknesses for impedance matching or inductance chokes.
> The hackaday technique assures such results repeatably.
> All acids must be handled properly, I have 30 years experience with 
> conc. NITRIC and never a problem. HCL is also dangerous, fumes,  and 
> can emit large volumes of chlorine if it comes into contact with 
> household ammonia cleaners.
> http://www.flinnsci.com/media/396140/acidsafety.pdf
>
> When nitric is etching copper it bubbles a bit and self stirs the mix 
> for cleaner trace edges I have found. Also the fine even bubble 
> generation reveals any improperly cleaned copper areas within a couple 
> seconds. Such areas can lead to longer immersion times which will 
> cause over etching of the properly cleaned areas. In effect it gives 
> me quality control feedback that other etchants don't.
>
> Further, the copper nitrate end product is beneficial to sewer systems 
> for restricting root growth, a fungicide or as a soak for preserving 
> outdoor wooden surfaces.
>
>   * Cupric Nitrate (Copper Nitrate) Cu(NO_3 )_2 �nH_2 O, green powder
>     or blue crystals which is soluble in water; used in electroplating
>     copper on iron; as a catalyst and nitrating agent in organic
>     reactions; component in rocket fuel; fungicides and wood
>     preservatives; textile dyeing and printing; pigment in ceramics;
>
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