Rick Sparber:
Lye crystals have been withdrawn from many markets because they were
being used to make illegal drugs and you can no longer purchase lye
crystals at your local grocery store or hardware store.
I used to buy it at my local Safeway market, but it is gone from there,
and all of the
other supermarkets in my area (Oro Valley, Arizona)
Roland F. Harriston, P.D.
∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗
On 3/30/2013 1:18 PM, Rick Sparber wrote:
>
> Todd,
>
> Oh, it self-heated to way over 120F. I suspect you use a much more dilute
> mixture.
>
> Rick
>
> -----Original Message-----
> From: Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>
> [mailto:Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>]
> On Behalf Of Todd F. Carney / K7TFC
> Sent: Saturday, March 30, 2013 1:09 PM
> To: Homebrew_PCBs@yahoogroups.com <mailto:Homebrew_PCBs%40yahoogroups.com>
> Subject: RE: [Homebrew_PCBs] lye
>
> 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@...
> <mailto:rgsparber%40aol.com>> 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%40yahoogroups.com>
> > [mailto:Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>]
> > On Behalf Of Roland Harriston
> > Sent: Saturday, March 30, 2013 8:34 AM
> > To: Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.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]
> >
> > ------------------------------------
> >
> > Be sure to visit the group home and check for new Links, Files, and
> Photos:
> > http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> >
> >
> >
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and
> Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
[Non-text portions of this message have been removed]