Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan" 
<stefan_trethan@g...> wrote:
>
> On Tue, 03 Jan 2006 15:48:13 +0100, Bruno St-Laurent <bsl88k@n...>  
> wrote:
> 
> > Hi guys I'm new using the homebrew mix of HCL 30% and H2O2 3%, and
> >
> > would like to know what is the best temperature for good etch 
time??? ,
> >
> > right now when i do a fresh mix, the etch time is really fast 
around 5
> >
> > minutes , but if a week later i want to reuse that mix now clear 
green
> >
> > color my etch time goes up to more than 30 minutes!!!!!!
> >
> >
> > Thanks
> >
> >
> > Bruno
> 
> It is problematic to heat this etchant because HCL will boil at 
like 50C  
> or something, and already below this temperature the amount of 
produced  
> fumes will increase greatly. So there probably isn't much to heat 
above  
> room temperature before things get nasty.
> 
> Use a bubbler.
> 
> You do know that you need fresh H2O2 each time, as long as your Cu 
levels  
> are still low?
> 
> ST
>
I do use a bubbler !!!, ok, then i need to get concentrated H2O2!! is 
it easily available ???