Homebrew PCBs

I've been using drug store 3% peroxide .... 100 mL mixed with 50 mL 
hardware store 30% muriactic acid.
I am NO chemist.
Do we have any chemists here that can tell us anything about these mixtures?
Like is it BAD to do 50/50 plus salt ... for any reason?




On 11/23/2016 08:35 PM, David Martin davemrtn@... 
[Homebrew_PCBs] wrote:
>
> I have been getting good results with a 50/50 mix of muratic and 3% 
> Hydrogen Peroxide, and I add table salt to accelerate the etching.
>
>
> On 11/23/2016 19:30, duwaynes@... [Homebrew_PCBs] wrote:
>>
>> When using muriatic acid and hydrogen peroxide, the etching time 
>> mostly depends on the concentration of hydrogen peroxide used.  I 
>> usually get 12% peroxide from a beauty supply store.  With this 
>> concentration mixed 2 to one with muriatic acid the etch time is 
>> around 2 to 3 minutes.  This is a very exothermic reaction, and the 
>> solution will get hot very fast.. You really have t o watch closly 
>> with this concentration, because it can over etch very quickly. I 
>> usually dilute this down to 6% to get around a 6 minute etch time.  
>> With the 3%  from a drugstore I usually have a 12 to 15 minute etch 
>> time.  Peroxide can decrease in concentration after it ages or 
>> exposed to air. in a nearly empty container.
>> DuWayne KV4QB
>>
>
> -- 
> David Martin - NA1MH - Mountain Home, Ar.
> -----------------------------------------
> How much longer do I have to wait for 'Hollywood' to leave the U.S.A. ?
>