Gum printers: what paper and sizing are you using?

[Barry S]

I just started doing some gum printing and have realized how critical the paper and sizing are to the process. The Strathmore Bristol Vellum I successfully use for cyanotype doesn't clear the highlights if unsized and doesn't coat well if sized with diluted matte acrylic medium. I also tried some hot press watercolor paper I had and it didn't work at all. Before I buy some new paper and sizing materials, I'd like to hear what paper and sizing formulas are working for other gum printers--especially papers that don't cost a fortune. Thanks.

 

[sdivot]

I use fabriano artistico extra white because it doesn't shrink. I use Gamblin PVA size, diluted 1:2. One or two coats. There are several different types of sizing methods, but I find the PVA easiest and quite effective. I don't think the paper is that critical for gum, the way it is for platinum, etc. For me it's all about the shrinkage, since I do multiple coats.
Good luck,
Steve
www.scdowellphoto.com

 

[phritz phantom]

i think the successful gum printing depends more on the size than the paper. i usually print on the cheapes and smoothest paper available.
while i've heard about people making prints with a size based on acrylic, for most people (including myself) it doesn't work. the most recommended and well-tested size is gelatin with some kind of hardener. lately the gamblin size, as already mentioned, has a good reputation. i'd rather try that or the gelatin, before buying new paper.
there is an article on alternativephotography from peter blackburn, who exclusively prints on unsized fabriano.

 

[TheFlyingCamera]

I use Rives BFK for paper, and the 250-bloom gelatin from Bostick & Sullivan (get their gum printing kit). They include a different paper (Lana Acquarelle) in their kit (you can order the kit without the paper if you want). The most important criteria in choosing a paper for gum is wet strength and resistance to dimensional change over multiple wet/dry cycles. Rives BFK is well-regarded for these characteristics, as is the Lana Acquarelle. The Lana Acquarelle comes in 2 strengths - 140lb and 300lb. The 300 lb is recommended for doing multiple passes, whereas the 140 is preferred when doing fewer gum layers as it is not as dimensionally stable as the 300lb.

 

[Barry S]

Thanks for the suggestions. It sounds like I can find some good candidate papers at the local Pearl art. I'll see if they have some of the Gamblin PVA and maybe I'll test some gelatin too. Can I use chrom alum to harden the gelatin or do I need glyoxal? Seems like I always need to buy one more thing for alt process.

 

[TheFlyingCamera]

Glyoxal is a good alternative to formaldeyhde, which is the preferred hardener. For a variety of reasons, the formaldehyde has issues, but it is considered to be the best. Some people report staining issues with the Glyoxal. I've not seen any references to using chrom alum for a hardener, one way or another, so you could give it a try and see what happens.

 

[Colin Graham]

Right now FAEW and glyoxal, in a 3% 250 bloom gelatin. I tried some glutaraldehyde, but couldn't make it harden gelatin at any dilution. Others have reported great success with it, so maybe I just got a bad bottle of it.

The glyoxal does have a slight yellow hue compared to plain gelatin which is masked somewhat by natural white papers, but much more apparent with bright white stock. I wash the sized papers in warm water after dry and it helps alot, but it is an extra step. I'm going to try some formalin next. But glyoxal works well- cures fast, the highlights clear easily, isn't as noxious to handle, etc.

I've heard that chrome alum leaves a distinct blue cast to the paper, and it takes several days to cure properly.

 

[Jeremy]

Rives BFK, Fabriano Artistico EW, and I also use Arches Platine & Cot 320 for gum over palladium prints. I size with Gamblin PVA Size at a range of dilutions depending on effect wanted. I have some new substrates I've been wanting to try, too.

 

[Kerik]

I use Fab Extra white and Rives BFK (mostly the former). I size with gelatin hardened with formaldehyde. Glyoxal will cause yellowing of the sizing unless you print soon after the sizing is applied. If you let it sit around for a few days or longer, it will yellow. I tried the Gamblin PVA size a few years back, but am not too fond of the surface it leaves. Glut did not work well for me either.

 

[Barry S]

I can't stand the smell of formaldehyde. Too many years in the lab, I guess. Glyoxal and glutaraldehyde are also aldehyde compounds, so I wonder if cinnamaldehyde might work. Better the smell of cinnamon than formalin! The yellowing with glyoxal is a pain. I'd like to size a batch of paper to last a couple months.

 

[Zby001]

I use Canson and Fabriano papers, and experiment with other brands. Even cheap papers may give good results. I found Fabriano more stain-proof than Canson, but this highly depends on how you size the paper. I always use 3% gelatin solution for sizing and harden dry sheets in chrome or potassium alum solution. I sometimes repeat the process. It's likely simplest and cheapest method and produces good and reliable results. Regardless of how good is your sizing, some pigments in combination with certain papers always produce stains. You can eliminate such pairs by experimenting and recording your results.


HTH,

Zby

 

[Kerik]

I apply the gelatin sizing with a glass or plastic rod. For example, on an 8x10 print I use about 4 ml of 4% gelatin with 3 drops of formaldehyde included. This results in a 1-step sizing and hardening and the with tiny amount of formaldehyde being used the odor is nearly imperceptible. But, if you're very sensitive to it, it still may bother you. Once the gelatin is heated and ready it literally takes about 30 seconds per print to apply the sizing. Very quick and easy.

 

[Barry S]

Thanks for the specific recommendations--they're very helpful. How much do you heat the gelatin, Kerik? Also, where do you buy your formaldehyde and do you know the concentration? I dislike the odor, but I don't have any allergies.

 

[phritz phantom]

The yellowing with glyoxal is a pain. I'd like to size a batch of paper to last a couple months.

quoting judy seigel (because i haven't ever used glyoxal), the yellowing from the glyoxal can be avoided, if the (dried, i assume) paper is washed in a waterbath. so either make the prints quickly or soak it in a waterbath to get rid of the parts that cause the yellowing.

i'm dead scared of the aldehydes, so i went with the chrome alum road for a while. i got good results, then later, all went downhill and i got horrible prints. i can't really name a culprit, so i'm not sure, whether i can recommend the c.a. or not. i used appr. 0.2gr for 100ml of 5% gelatin.
now i'm trying pva sizes and get somewhat mixed results (prints absolutely fine, but the exposed gum gets very vulnerable again when re-wetted, so multiple layers are impossible). it's not gamblin, different brand.

I always use 3% gelatin solution for sizing and harden dry sheets in chrome or potassium alum solution.

i see you are using the hardener in a seperate bath. could you tell me a little more about the strength of the solution and time ... and everything else important? and how long does the solution keep in your experience?
i've only been adding it directly to the gelatin so far. see above.

 

[Jeremy]

quoting judy seigel (because i haven't ever used glyoxal), the yellowing from the glyoxal can be avoided, if the (dried, i assume) paper is washed in a waterbath. so either make the prints quickly or soak it in a waterbath to get rid of the parts that cause the yellowing.

Tried this and it didn't help. Could be something in her or in my water that is making the difference, but just wanted to say that a waterbath for yellowed glyoxal isn't a cure-all in every situation.

 

[Kerik]

I heat the gelatin to about 130F using a simple $10 Dead Link Removed. I like these because they are cheap and won't overheat the gelatin. The formaldehyde is a standard solution of 37%. I got a pint of it from a local pharmacist about 8 or 9 years ago for about $15. I explained what I was using it for and I guess I sounded like I knew what I was talking about. Since I use so little of it for each print I still have over half of it left - and I mostly make 14"x17" and 17"x17" prints. I see you can get it at Chemsavers.

I've read Judy's approach to soak the paper again after the sizing dries. I assume this may work for some, but I'm not interested in adding yet another hassle step to the paper preparation process.

 

[pjbtx]

OK, so after using two papers, a bristol and a watercolor paper, you've come to the conclusion that you need to add size to your paper. While I would agree that adding the type of size options which have already been suggested to you in previous responses are valid and effective, I would offer the option that you could simply use pigments which do not leave a stain on your paper (which could be the cause of your ruined highlights).

Of the two papers you mention, I would return to the watercolor paper and find pigments which when applied, dried, and rinsed do not leave a stain. Two avenues you could try first are the cadmiums and the earth pigments. If you can locate some pigments which will perform as such, go back and try again.

I have found watercolor papers sized with AKD offer the artist a broader choice of pigments which will not leave a stain than other papers sized by the manufacturer with more traditional sizing such as gelatin. Be sure, however, that your "stain" is not the result of overexposure or thin negative density.

It seems the web and the written literature is filled with information providing a variety of sizing approaches. In fact, so much so one might get the impression that adding size is an absolute requirement for gum printing. I wish to say, based upon my own work and the work of others, that simply is not the case. Rather, it is possible to adapt the process to successfully work with papers sized as they are out of the package—and that is something rarely mentioned which is, most quality paper, especially of the watercolor variety, is already sized by the manufacturer.

Having stated that, I do think adding size is important for artists who need a much broader range of color options or desire a smoother paper. For them, the sizing already within the paper is not sufficient. All gum printers must come to their own conclusions concerning size based upon desired objectives and personal inclinations.

Peter J. Blackburn
http://www.alternativephotography.com/artists/peter_blackburn.html

 

[Barry S]

Peter-- Thanks. I bought a few sheets of Fabriano Artistico Extra White and Rives BFK today. I definitely plan to test these papers with and without sizing. I note that the Fabriano is already sized (not sure about the Rives), so I'd be happy if I didn't need the extra step. I'll also be testing some different pigments, but it's always helpful to learn exactly what's working for other practitioners.

 

[sdivot]

Kerik,
Did you try PVA straight or diluted? I ask because you say you don't like the surface it creates. I dilute it 1:2 with water, and use an old hake brush to apply a couple of coats. I actually have to mark the paper after sizing. Otherwise I would have a hard time being able to tell it was done at all.
Using it straight, on the other hand, leaves a definite sheen to the paper.
Everyone will come to their own favorite techniques, but using PVA has proven to be the greatest thing ever for me. No more heating and blooming gelatin, dealing with formalin, etc.
What a breath of fresh air.
Best,
Steve
www.scdowellphoto.com

 

[Kerik]

Steve I did try different dilutions, but don't remember how much. The bottom line was, gelatin and formalin works so well for me and it's so fast and easy that I didn't pursue PVA very far. If it ain't broke...

While I do understand your personal desire to avoid formalin, a few drops per print don't concern me. And I don't consider putting gelatin in water for 20 minutes and heating it up to be anything close to a chore. There are always other things to do while that's happening. Once everything is ready, I can fill my drying screens with sized paper in no time. I'm glad you found a method that works well for you. Your gum and gumover work is outstanding.

As for un-sized paper for gum... I know it is doable, but it's not what I would recommend for someone just starting out. Especially if they are pre-shrinking or acid treating the paper beforehand (for gum over platinum).

 

[pjbtx]

In an attempt to provide another viewpoint, one that is just as valid and doable as other approaches posted, I believe endeavoring to work with a paper without adding size, especially those incorporating formalin or glutaraldehyde, is exactly where a beginner should start. It's one less step in the process, one less variable, one less set of safety precautions which need to be followed, less expense and less time. The key is to find pigments which will wash cleanly from the chosen paper.

All of those factors and more, in my opinion and with all due respect, help to make this approach quite “doable” for anyone. Here in the Dallas area, it’s great fun to both demonstrate and assist upper elementary (5th/6th graders) students in making gum prints. Other than the dichromate, there are no additional chemicals for which to exercise precautions. Using non-staining pigments (i.e. pigments which do not stain the chosen paper, usually a Fabriano paper), the students can easily make fantastic prints with wonderful definition and contrast. With this approach it is also quite easy to teach staining and non-staining principles and effects.

As for paper shrinking, papers manufactured with AKD are very robust and will maintain their excellent sizing properties even after a prolonged soaking—in fact, even after many, many prolonged soakings.

Making the decision to add supplemental size can always come later. Let me emphasize that there are valid reasons to use supplemental size—that is a fact. However, the only point I wish to make is that exhibition and gallery quality gum prints can be made on paper without the application of supplemental size—and it’s really not as difficult as one would imagine.

P.S. I don't believe the original poster mentioned gum over platinum—not a process for someone starting out, in my view. If he did, then I would defer to others for additional comment.

 

[dwross]

I'd like to add vote of support for gum printing on Fabriano Artistico without additional sizing. I only gave it a try about a month ago and I was very pleasantly surprised by how little shrinkage and staining there is. I didn't even bother to pre-shrink. For the last two years I have printed gum over handmade silver gelatin paper, and my assumptions about gum in general have come from those experiences. 'Silvergum' shrinks a lot and I've recently come to the conclusion that it is the gelatin emulsion that is shrinking and not so much the paper itself.

So... a question for folks with a broader experience with gum than I have: Is it possible that too much is being done to the paper before the first gum layer actually goes down? (And, of course, I'm only addressing Fabriano here.) If the pre-shrinking step is mainly serving to remove Fabriano's internal sizing, and then following that step, a hardened gelatin sizing is being applied that itself shrinks, is all the extra work just serving to make matters worse, not to mention more complicated?

My apologies if this has been extensively covered somewhere else. There's so much gum info out in the world and so much of it seems to be anecdotal, it's hard to always to know what's what. I've just written a tutorial about silvergum printing for my website. I talk a bit about gum on plain Fabriano, but my personal experience is limited. I don't want to mislead anyone through over-simplification, but it does seem that printing on plain Fabriano is a wonderfully simple proposition.

d
http://www.thelightfarm.com/Map/Silvergum/SilvergumAdvanced/SilvergumPart4.htm

 

[Loris Medici]

Well, not that I think I have a broader experience with gum than you, nevertheless I wanted to mention that I don't find Fabriano Artistico usable without additional sizing (whether I preshrink or not) and also I don't find the paper much dimensionally stable. (Again, whether I preshrink and/or size or not...) I use the 300gsm (140lb?) version BTW. (Both old Fabriano Artistico / new Fabriano Artistico Traditional White and new Fabriano Artistio Extra White.)

Therefore, I think it depends... (On particular materials / working conditions and procedure.) I may elaborate later if you need.

OTOH, I still think Fabriano Artistico is one of the best papers around for gum printing.

Regards,
Loris.

...
So... a question for folks with a broader experience with gum than I have: Is it possible that too much is being done to the paper before the first gum layer actually goes down? (And, of course, I'm only addressing Fabriano here.) If the pre-shrinking step is mainly serving to remove Fabriano's internal sizing, and then following that step, a hardened gelatin sizing is being applied that itself shrinks, is all the extra work just serving to make matters worse, not to mention more complicated?
...

 

[Loris Medici]

BTW, in my understanding, preshrinking is not done to "remove the paper's internal sizing" (that's something we absolutely don't want to do) but to relax the paper's fibers as much as possible, in order to "reset" their position/orientation, letting them to reorganize in a pretty similar fashion in the subsequent development baths, for better dimensional stability. Also, preshrinking raise the paper's nap a little bit which is good for adhesion of gum emulsion. (Significant for the first layer only; subsequent layers will have a paper with raised nap after the first development bath whether you preshrink or not.)

Regards,
Loris.

...
If the pre-shrinking step is mainly serving to remove Fabriano's internal sizing
...

 

[dwross]

Thank you, Loris, for the excellent info. (And your opinions about gum carry a lot of weight with me.) My thought on removing the internal sizing was that it might be happening without being the intended purpose of a pre-soak. I agree, that wouldn't be a good thing. I don't know enough about what 'internal sizing' is. Perhaps it can't be washed out, at least not easily. It's obvious I need to study up on the ins and outs of paper.

I'll have to pay closer attention to paper nap next time I print. I haven't had adhesion problems on my first layers, but you've convinced me to experiment with pre-shrinking, and I'll also go back and study the threads about external sizing.

Thank you very much,
Denise