I used sodium hydroxide (lye) all the time in an industrial setting to make
aluminum lettering plates. The process called for the solution to be heated
to 120 degreeF. I don't remember the dilution rate. Fumes? Just do as you
did -- outside.
On Mar 30, 2013 8:44 AM, "Rick Sparber" <rgsparber@...> wrote:
> ∗∗
>
>
> Roland,
>
> In this case, I am etching aluminum, not copper. I know that ferric
> chloride
> does not do much to aluminum.
>
> I chose lye because it was easy to find at my Ace Hardware store and was
> very low cost. Yet I see that the stuff is very active at full strength. I
> assume that if I mix in more water, it would not be as aggressive nor
> generate as much heat.
>
> If I didn't use lye, what other commonly found chemical could etch
> aluminum.
> I tried drain cleaner but it was far too slow and stopped etching after a
> few minutes. I was left with a very slight roughness in the exposed area.
>
> Rick
>
> -----Original Message-----
> From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
> On Behalf Of Roland Harriston
> Sent: Saturday, March 30, 2013 8:34 AM
> To: Homebrew_PCBs@yahoogroups.com
> Subject: Re: [Homebrew_PCBs] lye
>
> Whew!
>
> A really bad idea!
>
> There are so many less dangerous materials that have been used to etch
> PCB's
> that have proven to be relatively safe and very effective over the last
> 50 or 60
> years.
>
> The task is not that complex or hazardous.....why make it so?
>
> Roland F. Harriston, P.D.
> ∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗
>
> On 3/30/2013 7:31 AM, Rick Sparber wrote:
> >
> > Has anyone used lye to etch aluminum through photo resist?
> >
> > As a test, I put a strip of aluminum in lye plus water and after 15
> > minutes the strip was half of its original thickness. So there is no
> > doubt that lye can etch VERY deep. But the chemical reaction generated
> > a lot of heat and the tape I had on there quickly floated off. Next
> > time I will use more water.
> >
> > I did have the lye and aluminum outside while I watched from inside.
> > Nasty fumes!
> >
> > Thanks,
> >
> > Rick
> >
> > [Non-text portions of this message have been removed]
> >
> >
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
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