I am a new subscriber to Orchid Digest and was really surprised to
see several messages about spray etching silver. It
just so happens my husband recently made me a spray etcher that is
wonderful! I took photographs of a spray etcher that Linda
Threadgill’s husband made. She had given a class on “spray
etching copper” at Mendocino. She sold her machine to Susan E.
Wood. I checked with Linda Threadgill to see about buying one, but
her husband didn’t want to make them any more. Since then I heard he
is making them again and they cost $1000.00. This is what I " heard"
from other friends. You would have to contact Linda Threadgill
about this. Anyway my husband did make one for me using the
photographs I took of the machine. He scrounged around in a scrap
place he goes to and found most of the parts. But the parts can be
bought new from U.S.Plastics , they have a web site and you can order
a catalog. The “Little Giant Pump” costs about $200. Hoses, pvc pipe
and etc. can be gotten at a hardware store. The spray nozzles are
another thing , I found them on the web at “Spraying Systems Co.” at
www.spray.com. They will send you a wonderful catalog and the web
site shows you all the the types of spray nozzles and what they do.
They will also give you the name and address and phone number of the
company in your area who sells these wonderful nozzles. I don’t want
to infringe on Linda Threadgill. I did ask , if it was O.K. to take
pictures of the spray etcher and make one if it was possible, and was
told that she had said to go ahead. When I contacted her I only
wanted to buy one and hadn’t thought of making one myself. She
didn’t offer any plans and since I am not planning to make them for
sale, I think its O.K. If there are those who are interested in
making a spray etcher I would be happy to find out how
much a set of my pictures would cost to copy and send them to you.
There are 19 pictures. Also my spray etcher is dedicated to etching
silver. I use ferric nitrate solution which I got from Springfield
Chemical. They have an 800 number, 800 683 3224. The ferric
nitrate comes in crystals in 5 lb. jars. I mixed this with distilled
water. A 55% crystals to 45% water is what you want. My notes have
gone on vacation but I wound up with 2 gallons of solution, which is
plenty because the solution just keeps pumping around and around.
The etching takes from 15 minutes to 45 minutes depending how deep
you want to etch. The etching is very sharp and I am told that you
can etch clear through the metal if you want. I haven’t tried this
yet but its on my agenda. I’m still experimenting with types of
resist and mostly I have learned what doesn’t work. I think PNP
paper works the best. I hope this is of some help to those who are
interested. I would like to get some feedback, I’ll locate my
vacationing notes about the solution proportions.and post them if
anyone is interested.