[Techniques] Photoetching

It was the summer 97 issue. The article was on Transfer etching.
It involved the use of A material called PNP blue. It uses a
xerox type photo copier or laser printer. It works well on copper
using feric chloride or dilute nitric acid. THe material is
available from Techniks Inc 908 788-8249 at 20 sheets for $30.00.
less per sheet in larger quantities. Enamelworks in Seatle has it
at 5 sheets for $10.00. I’ll post the adress and phone # later.
Jesse

PNP blue resist material is available from:

Enamelwork Supply Co.
1022 N.E. 68th St 
Seattle, Wa  98115
206-525-9271
Catalog $2.00

PNP blue works much better than overhead projection film. I have
had to do a lot of touch up of projection film acetate images
with an old style resist. Pnp blue require no or minimal touch
up. If you are doing deep etching for Champleve enameling you
will need to watch your minimum line widths to aoid undercutting
and loss of fine detail.Ferric Chloride is not particularly
dangerous but can stain. Watch you eyes. With a nitric acid etch
try to avoid bubble formatin by diluting the bath and going
slower. Again watch you eyes. Watch out for fume exposure
exspecialy with nitric acid, fumes can irritate your eyes and
cause lung irritation or damage. Work in a well ventilated area
and avoid the fumes. Enamelwork also has a Xedrox reprint of " A
Manual of Cloisnne and Champleve Enamweling" available for
$20.00. This is a great book that should be back in print. Jesse

Elaine - Ferric Chloride is technically not an"acid" but a salt.
So it doesn’t attack your clothing or your skin the way an acid
does. It will rust iron or stainless steel very quickly, and gets
rust stains on anything it touches, so clean up drips and spills
right away. I have not found it necessary to wear gloves. It
won’t burn your skin, though you don’t want to leave it on your
skin. It doesn’t emit fumes, so special ventilation isn’t
required. I do suggest recycling the used stuff via your toxic
waste disposal, if you have one in your area. Don’t just pour it
down the drain or into your septic system. It does have heavy
metals that can contaminate the water supply.

One thing about it that isn’t usually mentioned: after etching
it’s necessary to neutralize it or it will continue to discolor
the copper. (Actually this can be a very nice patina if you
sealed it with lacquer or wax.) Rinse the ferric chloride off,
then soak your metal in household ammonia for about 15 minutes.
This neutralizes the ferric chloride. (I usually do this after
I’ve removed the resist, as a last cleaning step.)

If you don’t want to go the PnP photoetch route, you can use all
kinds of resists with ferric: Sharpie markers, hard grounds
available from printmaking suppliers like Daniel Smith, asphaltum
varnish (Daniel Smith or Rio Grande) - just about any resist that
printmakers use. You can get some very interesting textures by
dabbing asphaltum on with a piece of sponge. Just be sure to let
the grounds dry well before etching (overnight is a good bet).
Most of these grounds are soluble in paint thinner, whereas the
PnP needs acetone/lacquer thinner to clean up.

Hope this helps!

Rene / Calif.

The article was in the summer 97 issue of Metalsmith. It came out
in July. I have found Techniks sometimes difficult to deal with -
they have had an answering service answer their phones and take
their orders, and the the service gives is not always
correct. It has been several months since I ordered, so maybe
they have corrected their workflow problems. The price on PnP
Blue goes down to $1.00/sheet if you buy 100 sheets. Another
source is Thompson Enamels in Kentucky. Their price is
$1.50/sheet.

I have found a few variations from the techniques mentioned in
the article, mostly in terms of ironing the sheet on. I have not
had luck at all in “tacking the sheet down around the edges” as
the article suggests. The sheeps wants to bubble in the middle if
I do this. Instead I start at one edge and work across. You want
your iron as hot as it will go without melting the sheet. Good to
test this first, as all irons are different. The metal needs to
be hot before the stuff will stick to it. It takes awhile for the
iron to heat the metal with larger pieces. You can preheat large
pieces of metal on a hot plate. Bubbles will often develop in the
sheet because it warps as it heats and wants to curl. These can
be “broken” by making tiny slices with an Xacto blade and
immediately ironing the area down. I use a wooden burnishing
tool with a flat edge to rub the toner on. The tip of my iron is
just not enough pressure to transfer detail consistently.

The blue stuff on the film will transfer as well as the toner.
This is a resist also, but sometimes with the burnishing it
smears into detail areas. I hold the metal under water after
removing the sheet and scrub very gently with a green scotchbrite
pad to remove the blue material from the areas where it has
smeared. You’re not trying to remove all the blue from the metal,
just the spots where it has smeared to obscure the fine details.
The black toner seems to be unaffected by this scrubbling, if
you’re gentle.

Places that don’t tranfer can be filled in with asphaltum
varnish or hard ground. This needs to dry for awhile before
etching. The resist will hold up for hours is ferric chloride,
except for thin detailed areas where it disappears because of
underbiting. After etching, the resist is removed with lacquer
thinner or acetone.

The article suggests you need a strictly black and white image
before the technique works. However, I’ve achieved some pretty
cool textures with grays. This texture can translate as a "gray"
if you’re putting a patina on the piece later.

Hope this helps. Gook luck!

Ren=E9 / No. Calif.

Did you know that you can “iron” images from your laserprinter
directly onto the metal? It works better than PnP Blue and holds
up to ferric incredibly well.

-k
Karen Christians
M E T A L W E R X
416 Main St.
Woburn, MA 01801

@metalart

Current Artwork:

Gracious! I’m getting so much helpful info. on etching I just
may have to try it again! Since that little post got a bigger
response than I expected, I figure I ought to tell you what I use
to apply the resist (hence my lack of interest in PNP).

I use the Rio “Etch Master” System. Which is not so much a
system really – just a blue resist that can be silkscreened. To
silkscreen it I use the Riso Print Goco, a Japanese card and T
shirt making home use item. It is now down to about $80. and is
available from Sax Art and Craft, Pearl Art and Craft, (Catalog
and Store) and some local business machine stores which
specialize in Riso’s larger machines.

The Print Goco makes a non-emulsion master using flashbulbs.
Then you take it off the machine and put the master in a tub,
make a tape hinge and squeegee the resist. This part is in the
Rio catalog. They still sell this, but not the Printer. The
Print Goco, incidently, was sold in the display and packaging
catalog. I also use it to print T-shirts, earring cards,
invitations, etc. Multi-color printing is possible. It’s
really a wonderful thing.

-Elaine
Chicago, Illinois, USA
Midwest

I got a Print Gocco before I discovered PnP and ended up
mothballing it. It worked OK, but all that cleanup with paint
thinner of the asphaltum on the screen? YUK. Also, the flashbulbs
and screens are very expensive. I’m experimental and want to try
a lot of different etched textures, etc. and I found this system
to be cumbersome. Also, I wanted to etch larger pieces than this
system would allow (the limit of my unit was only about 3 x 5
max). One plus: it does screen asphaltum varnish which is
resistant to nitric, so it’s a good method to use with silver.
And it’s true that there are a lot of other wonderful screen
printing uses for it, which I never tried. (I may dust it off . .
.)

Re: the PnP transfers, someone said they just place the iron
down flat on the film with a cotton cloth in between. I’ve tried
ironing the entire piece at once like this, but it trapped too
many air bubbles. I think it depends what size your transfer is.
I tend to do larger pieces (4" x 4" and larger). If I heat too
large an area at once, the film distorts unevenly and traps air.
With small pieces of metal, this isn’t so much of a problem. If
there is a way to solve this problem, I’d appreciate hearing
about it.

Rene

I usualy do half sheets of Pnp blue 5-1/2"x 8" on 6" wide metal
stock. The iron gets most of this covered with the first plop
down. My Cannon PC-11 photocopier feeds the half sheets just
fine. I don’t have a lazer printer but I think you get better
carbon transfers (darker) from lazer printer output than from
most photocopiers. Acetate transfers would then work better.

Jesse

When I use PNP paper as a resist, I begin by ironing one small
section. I start by holding the iron still (with not cloth or
anything else between the iron and PNP) until the PNP kind of
sticks. Then I continue to do sections of the metal. When the
resist looks black and the design is visible through the plastic,
I know that the resist has transferred to the metal. I let the
metal cool then pull the PNP off. --Vicki Embrey

Some tips along this thread:

Warping of the carrier sheets–If you’re using clear acetates,
try using a different kind, or lowering the temperature of the
iron. Very thin acetates are prone to warping. Medium to
heavy-weight acetates will hold up better to high heat. If
you’re using PnP, definitely lower the temperature of the heat
source the first sign of any warping or bubbling. PnP requires a
much lower temperature to transfer, approx. 275 degrees
Farenheit.

How to keep the carrier sheet from moving while
transferring–simple solution is to tack the carrier sheet to one
side of the metal with ordinary transparent “scotch” tape. It
serves as a register also. If it melts, no problem, you just
have additional resist.

The iron surface isn’t large enough or has uneven heat
distribution–Some associates of mine solved the problem by
getting a waffle iron that has reversible plates on it. One side
of the plate has the waffle pattern, the other is smooth. It has
an adjustable thermostat, and an 8" square surface area. Is it
too late to hit the garage sales?

Another iron tip–Turn the iron upside-down, with the metal
placed on top. If you’re ironing with the iron on top, you take
fate in your hands with uneven pressure. You can’t see what
you’re doing, you really have uneven heat distribution and you
take chances with shifting the carrier sheet which will cause the
design to smear.

Neutralizing the acid–Ferric chloride is an acid, even though
it is a salt. It’s pH is acidic, and it must be neutralized with
a base (alkali). The easiest and cheapest is plain old ammonia.
It’s already liquid, and it does a thorough job. I follow up
with a dip in Sparex to remove any oxidized residue, with another
dip in ammonia solution to neutralize the Sparex. If you don’t
neutralize the acids thoroughly, your patinas will have a
problem with not sticking, having uneven distribution or having
awful colors.

Getting gray scales in etching–It’s difficult but not
impossible. One trick is to use texture to represent the gray
scale, such as hatching or bayering. Another method is to use a
graphic editing program to “posterize” the photo or drawing. This
can also be achieved by increasing the contrast/brightness ratio.
Just remember that etching must remain stark black and white.
Traditional gray scale will not work successfully with these
types of etching using the acetate sheets.

Katherine Palochak

Another good heat source for adhering PnP Blue Resist is to get
a waffle iron with flat plates on one side, then put the metal
on the flat plate and heat (you will need to experiment with
temperatures but have found that light waffle works best on
mine) with the PnP Blue face down on the metal. I usually start
in the center of the Blue and stroke towards the edges with a
piece of cut-off illustration board or matt board while the
piece begins to heat. I have never had air bubbles using this
method.

Donna in WY

Katherine, re PnP transfers and uneven heat, etc., you said to
turn the iron upside down and place the metal on top. I’m not
sure I understand how this would work. I take it you mean you’re
heating the metal from underneath, and the PnP is on top of the
metal. But how are you applying pressure to the PnP to get the
image to stick? I like your idea of the waffle iron. I read
somewhere else that someone used a dry mount press (used for
photos). I wish these weren’t so pricey.

My problem with the PnP “warping” has not been because the iron
is too hot, I don’t think. The film itself doesn’t “bubble”; just
that when larger areas of black are transferred, air tend to get
trapped. I think this has something to do with the design, as
well. Line drawings don’t seem to have this problem. Also, when
I’ve turned the temperature of the iron down, the image won’t
transfer at all. It’s just a problem that seems to occur when
using larger pieces of PnP.

Re: gray scales: I once has some of my images with grays printed
on the PnP with a laser printer. The screen setting used by the
printer created an ultra-fine cross-hatch on the print, which
transferred to the metal as a “gray”, especially when the metal
was darkened a little and buffed back. I was amazed at the
detail. A copier would have never done this.

Rene
No. Calif.

Katherine, re PnP transfers and uneven heat, etc., you said to
turn the iron upside down and place the metal on top. I’m not
sure I understand how this would work. I take it you mean you’re
heating the metal from underneath, and the PnP is on top of the
metal. But how are you applying pressure to the PnP to get the
image to stick? I like your idea of the waffle iron. I read
somewhere else that someone used a dry mount press (used for
photos). I wish these weren’t so pricey.

Rene, all irons have different handle setups, so it will be
necessary to experiment a little to see which method works best,
and allows the iron to be stable. What we’ve used most
successfully has been to mount the iron upside-down on a bench
pin, with the bench pin through the handle, then using a
graduated wedge from the opposite side. My iron has a nice flat
surface, so I use one of those flat bench pins made from a 1" X
4" (they have a “C” that goes through a hole in the pin for
adjusting to different thicknesses of work areas). An associate
couldn’t get her wierd iron handle to work on any bench pins, so
she started with blocking it upside-down on bricks, then later
knocked together some scrap wood with an opening in the middle
for the handle.

I’ve found it doesn’t require to much pressure to transfer the
resist. I found an old playing card for my burnisher. It’s
fairly thick and doesn’t have the plastic coating on it to melt.
Stoke the burnisher in one direction only, preferably from the
side of the register (“scotch”) tape to the opposite side. It
seems to only require as much pressure as you’re able to get from
a flimsy piece of card. If I can’t find my card, I use a piece of
folded paper, 8-1/2" X 11".

I’ve used this method successfully for transferring a variety of
patterns. I’ve never had problems with designs with large areas
of black. Some of my designs have been based on large ratios of
black and white, such as Anasazi, Hohokum and Pueblo designs, as
well as very bold pattern zebra stripe patterns. I think the
secret lies in getting all of the metal surface a consistent
temperature at the same time. On my iron, the maximum sheet of
metal I can use is 4" X 6". I usually set up my patterns on the
PnP with this size in mind, and do a whole sheet of metal at once
in this size. Try transferring the designs with the iron
upside-down, metal next, and PnP on top, and see if you have
better results.

I guess I’m going to have to invest in a laser printer. Your
experiment with grayscales is intriguing. For others, the reason
inkjet printers won’t work is because their inks aren’t
carbon-based. Laser printers and photocopiers use carbon-based
toners. If you have a steady hand, you can draw directly on the
metal with India ink or permanent markers, but it is very
fragile. The PnP must somehow combine with the toner to
plasticize the resist a bit, providing a tougher resist.

Katherine Palochak, Wyoming

Please excuse excuse me if my question has previously been
covered in this list. I just joined as of 2 Sept 98. I haven’t
yet used PnP but I understand the temperature is important.
Has anyone ever used a rubber mold vulcanizer with PnP? Just a
thought. I want to transfer small designs of about 10-15mm
diameter. Do I need to burnish? I’ve read that some do not
burnish their designs.

Another technique which may be comparable to turning your iron
upside down is to use a hotplate to transfer your PnP paper
resist. I’ve done this using copier images on acetate. Place a
flat piece of brass on top of the hot plate burner and turn the
hotplate onto a low to med. low temperature. Place your metal
piece with the transfer image on top on the brass. The transfer
image should be taped in place. Burnish the image with a metal
burnisher. Remember to use tweezers to pick the metal up when
through. By the way, I have successfully transferred larger PnP
images to metal using an iron. I tape the image down on one edge
and begin by ironing a small section along that same edge. As
the PnP paper begins to stick to the metal, I find that I can
move to another section. I keep moving toward the other side of
the piece, thus not trapping any air bubbles. The image becomes
visible through the plastic once it has transferred which helps
you know when you’ve ironed it enough. Let it cool, then pull off the paper!