How did you protect the back of the aluminum. I tried applying wax but I
think it melted off. Also tried electrical tape and it fell off. Maybe the
common factor here is the heat generated by the too strong lye/water
mixture. I was thinking about using a Q tip and just dip it in the lye/water
mixture and dab it on the masked off area.
I've had very poor luck with toner transfer. The closest I came to success
was with copper.
I will be using my new spray on photo resist and a contact print. But first
I want to perfect the etching process with just masking using tape, wax, or
??.
Rick
-----Original Message-----
From:
Homebrew_PCBs@yahoogroups.com [mailto:
Homebrew_PCBs@yahoogroups.com]
On Behalf Of Harvey White
Sent: Saturday, March 30, 2013 8:36 AM
To:
Homebrew_PCBs@yahoogroups.comSubject: Re: [Homebrew_PCBs] lye
On Sat, 30 Mar 2013 07:31:42 -0700, you 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 so a long time ago with photoresist, the back of the aluminum was
protected, and it was potassium hydroxide not sodium hydroxide. It did work,
though. I filled the etch with ink then lightly sanded the surface. Worked
well.
I'd do it with toner transfer were it not for the problems with getting the
entire piece of aluminum to temperature (as well as potential thickness
problems. Possibly a T shirt press would work.
also need a negative mask.
Harvey
>
>
>
>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]
------------------------------------
Be sure to visit the group home and check for new Links, Files, and Photos:
http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links