Using asphaltum on copper

Jewelry Discussion
1

Hello. I’m new to the list and have just looked through the
archives, but didn’t find any info on my question. So here 'goes:

I’m using asphaltum as a resist on copper for acid etching. what’s
the best way to remove the asphaltum after the etching?

Thanks in advance for any insight on acid etching copper!

Steffanie

2

turpenoid… you can purchase this turpentine replacement at an
art supply store… goo gone citrus based solvent might also work…
why don’t you think ab’t trying the pnp ferric chloride for
copper/brass… ferric nitrate for silver… there is a wealth of
in the archives Re: this topic

aloha

3

Steffanie, I don’t know if this is still the approved way, but eons
ago I was taught to grasp the piece of copper with a pair or tongs
or pliers,and while holding it over a bucket of water to burn the
asphaltum off with a torch. This is a smelly process, and I don’t
know how safe it is to be inhaling the fumes. Perhaps there is a
better way.

I now use PNP as a resist for etching, and use ferric acid as my
mordent. You might want to check this process out.

Alma

4

As an old printmaking, turned jewelry, my advice would be to use
turpinoid, artificial turpentine, to remove the asphaltum

Peace,
Richard

5

I do a lot of copper etching with ferric chloride. I use laquer
thinner to remove any resists I have on my copper or brass, and I
make sure that I use it outside or with excellent ventilation or a
respirator, and that I throw away all of the paper towels or cloth
used in the dumpster behind my building (it can spontaneously combust
if kept in your garage or room). If you have further questions, I’d
be happy to try and answer them.

Sandi Graves, Beadin’ Up A Storm
Stormcloud Trading Co (Beadstorm)
http://www.beadstorm.com/
Saint Paul, Minnesota USA
651-645-0343

6 
what's the best way to remove the asphaltum after the etching?

turpentine on a rag gets the asphaltum off,

cheers, Christine in Sth Australia

7

Christine: Are you aware that you can use a black felt tip marker
for the resist on copper and brass if you are using ferric chloride?
The U.S. brand I use is called a sharpie I don’t know if that brand
is available in Australia if so don’t use the razor point it doesn’t
put out enough ink,go to the med point.Try this it can save you
untold hours with that little brush. Another time saving tip. Don’t
paint the backs use peel and stick plastic available in craft
stores. It you have to use asphaltum I have always used turpentine
to remove it, it is quick and easy.

Dave Owen

1 Like
8 
If you have to use asphaltum I have always used turpentine to
remove it, it is quick and easy.

For what it is worth, I mostly no longer use solvent to remove
resist. I rub it off with 0000-grade steel wool.

Noel

9 
you can use a black felt tip marker for the resist on copper and
brass if you are using ferric chloride? The U.S. brand I use is
called a sharpie Don't paint the backs use peel and stick plastic
available in craft stores

thanks dave for the tips, I have read about the sharpie pens, bought
one but not tried it yet. Didn’t know about the adhesive backings
though… ta again, Christine in sth Australia

10 
...Don't paint the backs use peel and stick plastic available in
craft stores

That black electrician’s tape works, too (overlap the edges) for
covering the back of things you’re etching. Masking tape is not
suitable.

Judy Bjorkman

11 
...Don't paint the backs use peel and stick plastic available in
craft stores

Clear Packing tape is wonderful too.

Ellen Starr
Starr Design

12

When etching, I use contact paper on the backs of my metal, and it
holds up well… I understand that 3M packaging tape (the wide kind),
also holds up, but I have not tried it.

Alma

13 
Don't paint the backs use peel and stick plastic available in craft
stores

That black electrician’s tape works, too (overlap the edges)

And I use the 2" wide transparent tape you use for sealing packages,
works fine, again overlap the sections.

Donna in VA

14

Most copper plates used for printmaking now come with a sheet of
adhesive plastic on both sides, one to protect the surface to be
etched which is of course removed, and the other sheet being left in
place as an acid resist.

Brian Corll

1 Like
15

I’ve successfully used contac paper and duct tape (overlapped).
Because I deep-etch, I usually have several layers of backing tape
to help avoid any burn-through of my acid.

Sandi Graves, Beadin’ Up A Storm
Stormcloud Trading Co (Beadstorm)
http://www.beadstorm.com/
Saint Paul, Minnesota USA
651-645-0343

16

Clear packaging tape does work!

Jesse