Mounting paper on solid backing for gum printing

[Xandros]

Hi all, me again ...

The thing is, even with two pass pre-shrinking of the paper in hot water, I only get perfect negative registration only for the first two, maybe three layers of gum. Then, the paper slightly shrinks anyway, enough to be noticeable at least on one of the corners ...

I've read a great description of the gum printing workflow Keith Taylor uses here :

http://unblinkingeye.com/Articles/3CG2/3cg2.html

Here's how Keith uses the solid backing :

"Traditional methods used for producing three color gum prints begin with pre-shrinking a sheet of watercolor paper so that multiple washings will not change the paper’s size and throw the subsequent layers out of registration. The paper is dried and re-sized to keep the emulsion on top of the substrate, rather than sinking into the weave. Taylor, being a maverick, diverged from this accepted method and pursued instead a technique advocated by printing maven, Dick Sullivan. It required mounting the paper on a solid backing for the entire printing process – thus avoiding shrinkage and re-sizing. Sullivan had successfully practiced this concept with his own gum prints over four decades ago. He based it on a technique that he believes may have been first practiced by Pictorialist, Heinrich Kuhn. Following Sullivan’s lead, Keith had thin sheets of Aluminum cut and pierced to hold his paper and seat registration pins. The pins gave him a classic way of keeping all his negatives in perfect registration. He mounts his watercolor paper on its backing using a hot press and a single layer of Fusion 4000 tissue as its binder."


I am wondering if there would be any other less expensive and easier method to mount the paper on some solid backing for the whole operation. The average beginner printer may not have a hot press and the money to glue every piece of paper using the special tissue, especially as many of the prints go to the trash bin at the beginning ...

 

[sdivot]

Well, I don't know what to tell you about the hot press. Or the tissue. I suppose you could spring for the tissue and put something on it heavy enough to keep the tissue and the paper together, and then use an oven. I'm not sure that will work, and I hesitate to recommend it. So good luck with that.

As to mounting on hard substrate, I use plexiglass in stead of aluminum. It seemed more readily available at my local hardware store. And I can cut it myself. now have no issues with shrinking or registration (unless I'm very careless).
Thanks you Keith Taylor!

Steve
www.scdowellphoto.com

 

[Xandros]

plexiglass seems fine. could you tell me a bit more about the way you mount the paper on it and keep it glued even through the several development baths ? Thanks !

 

[sdivot]

Keith Taylor uses Fusion 4000. I use I use Dry-Lam ColorTac, from B&H Photo Video. These products allow removal by re-heating. A lot of the different types of tissue are permanent. You don't want that, unless you want your print to be permanently attached to plexiglass!
A heat press is needed though. I suppose you could use a clothes iron as well.
Good luck,
Steve
www.scdowellphoto.com

 

[Xandros]

Ok thanks for the tip ! looks like this kind of tissue is the best way to go then ... does it peel off the paper back or just off the plexiglass?

 

[donbga]

Ok thanks for the tip ! looks like this kind of tissue is the best way to go then ... does it peel off the paper back or just off the plexiglass?

You aren't going to get much advantage from using the plexi unless you can punch register that. IOW, you can print tri-color gum without fixing the paper to aluminum or other material, though a punch registered print will much sharper, especially in larger sizes. But if you are just starting out I would make small prints without the complication of dry mounting the paper.

 

[donbga]

Keith Taylor uses Fusion 4000. I use I use Dry-Lam ColorTac, from B&H Photo Video. These products allow removal by re-heating. A lot of the different types of tissue are permanent. You don't want that, unless you want your print to be permanently attached to plexiglass!
A heat press is needed though. I suppose you could use a clothes iron as well.
Good luck,
Steve
www.scdowellphoto.com

Steve,

Thanks a lot for the tip about the Dry-Lam Color Tac and the plexiglass. What thickness of plexi are you using? I have a 4x8 foot sheet of very thin plexi that I think would work very well. Great tip!

 

[Xandros]

Hi donbga !

I'm printing A4 prints maximum and even though I pre-shrink the paper twice and use pins to register the negative, the thing is that after 2/3 layers, the paper gets about 1mm less in diagonal than the negative, so I am not able to punch my pin in the hole any more I've tried different watercolor 300g/m papers and all of them seem to have this issue. I'm not into tri-color really, but multi-layer monochrome gum with deep blacks so I can't really stop after 2/3 layers most of the time ... Maybe doing something wrong though.

 

[donbga]

Hi donbga !

I'm printing A4 prints maximum and even though I pre-shrink the paper twice and use pins to register the negative, the thing is that after 2/3 layers, the paper gets about 1mm less in diagonal than the negative, so I am not able to punch my pin in the hole any more I've tried different watercolor 300g/m papers and all of them seem to have this issue. I'm not into tri-color really, but multi-layer monochrome gum with deep blacks so I can't really stop after 2/3 layers most of the time ... Maybe doing something wrong though.

What kind of paper are you using, and how are you pre-shrinking it?

You can humidfy the paper by making the back of the print slight damp. See if this will expand the paper fiber. I've never had that much shrinkage after pre-shrinking paper, but I suppose anything is possible. BTW, I never punch holes in the paper and negative I simply register on the light box and tape the negative in palce on the paper.

 

[Xandros]

I tried fabriano artistico, somerset, hahnemuhle, BFK Rives and finally set to Lanaquarelle cold press (all of them are 300g/m)
I pre-shrink by putting sheets into hot water (about 40-50°C) for one hour (the water cools down to about 30°C by then), hang to dry, repeat.
Then size using gelatin + hardener (2 layers with drying in-between, with single layer sizing the whites are not perfectly clear after a few layers of gum. maybe I should size once, print 2 layers of gum, then re-size ?).
I don't have a light box, so punching works for now

 

[sdivot]

Before I started using the plexi, my registration was kind of hit and miss. I would think it was ok, and later find out I was off by a fraction. D'oh!
Fabriano artistico should not be shrinking like that. I've never noticed it shrinking at all, that's why people like it for gum.
I don't use a pin registration system. I can easily register the paper on the plexi substrate, especially if I print registration marks on my digi negs. If you're using analog negs, just carefully mark the corners with a pencil after you print your first layer. Then line up subsequent layers to those marks.
Don, I use a fairly thick plexi for larger prints, and thin stuff for small prints. It seems the thinner stuff sometimes bows a little, so I like the thicker material. Sorry I don't remember the exact thicknesses. I got it off the shelf at Lowes.

Xandros, when you peel the paper off of the plexiglass, the paper comes off clean and the tissue sticks to the plexi. You can then take a razor blade and scrape the tissue off of the plexi and it's ready to go again!

Steve
www.scdowellphoto.com

 

[Xandros]

Thanks for the tips Steve ! I now have to find someplace to buy this in Belgium

 

[donbga]

I tried fabriano artistico, somerset, hahnemuhle, BFK Rives and finally set to Lanaquarelle cold press (all of them are 300g/m)
I pre-shrink by putting sheets into hot water (about 40-50°C) for one hour (the water cools down to about 30°C by then), hang to dry, repeat.
Then size using gelatin + hardener (2 layers with drying in-between, with single layer sizing the whites are not perfectly clear after a few layers of gum. maybe I should size once, print 2 layers of gum, then re-size ?).
I don't have a light box, so punching works for now

When you shrink your paper do you interleave the sheets occasionally to make sure they are all fully soaked?

Don

 

[donbga]

Xandros, when you peel the paper off of the plexiglass, the paper comes off clean and the tissue sticks to the plexi. You can then take a razor blade and scrape the tissue off of the plexi and it's ready to go again!

Steve
www.scdowellphoto.com

That's a really great tip Steve. Thanks!

 

[Xandros]

Yes Don, I move & switch their places about every 15 minutes during the soaking phase

 

[donbga]

Yes Don, I move & switch their places about every 15 minutes during the soaking phase

Well as Steve said, I've never had that much shrikage with FAEW. I also use Rives BFK and it does shrink a bit more but visual registration with both papers usually isn't a problem with sizes up to about 8x10.

Good luck,

Don

 

[Xandros]

Thanks to everyone, i'll try fixing those issues somehow

 

[sdivot]

I'm not even shrinking my Fabriano. I just take it straight out of the package. The beauty of mounting to plexi, is that it stops shrinkage, and it stays perfectly flat for all your registration needs.
When you re-heat and peel your paper off the plexi, it will curl up like crazy. Just put it back into the press, turn it off, and let it sit til it all cools. This flattens it pretty well. Make sure you put something like wax paper or parchment between the press and the back of your paper. If you don't the residual adhesive may stick to your press!
I also mount the finished print to another piece of paper for support.
Steve
www.scdowellphoto.com
I forgot to mention, when you mount the paper to the tissue, you must cover the entire surface of the paper. Not just the corners.

 

[Loris Medici]

Well guys, I'm with Alex here -> somehow, my 300gsm Fabriano Artistico seems to do the same (change dimension considerably, even at A4 image size) even after a good deal of shrinking. The problem is not the paper, it's the thickening gum layer... You'll see a relief of the darkest tones (thicker gum layer) on the back of the paper. Gum shrinks when drying therefore the paper shrinks along with the image...

The only remedies I can think of are a) affixing the paper to a dimensionally stable support or b) using a heavier gsm (450, 600 or more ....) paper.

Regards,
Loris.

 

[Xandros]

Thanks for the hint Loris, makes sense to me that in fact it's the gum that shrinks. Maybe more layers but thinner would work around this ?

Also, would it be enough to use long strips of tissue to glue it along the 4 borders only, not the whole surface ?

 

[Xandros]

I posted a little problem regarding dry mounting here :

(there was a url link here which no longer exists)

 

[Katharine Thayer]

Well... some thoughts:

Paper is always going to expand when it's wet and contract as it dries, whether it's been preshrunk or not. The issue for registering is that when you print again, the paper should be the same size as when you printed it before. When I was printing a great lot of tricolor in the 90s, I could tell precisely by the *feel* of the paper when it was just the right dry to register, but I'm using a different paper now and don't have the same feel for this paper, so I have to judge by trial and error, by setting the negative on the print and looking to see if it matches. If the dried print is bigger than the negative, then it needs to dry some more; if it's smaller than the negative, it's got too dry and I dampen it til it matches.

As for the relief on the back, that only happens with some papers. It never happened with the Arches traditional that I used for 15 years or so; the back of a finished print was as smooth and flat as new paper, no matter how thick the gum on the front was, but it's very pronounced with the Arches bright white I use now. I don't think it has to do with the *gum* shrinking as it dries, but with the *paper* shrinking differentially with the thickness of the gum layer, and is related to characteristics of the paper itself.

 

[Xandros]

Ok ! in my case the paper is smaller after 3 layers, so I'll try the back-dampening method !

 

[Katharine Thayer]

Only after the third layer the paper shrinks, not after the first and second soakings? I'm sorry, but that doesn't make any sense to me. But never mind me, carry on....

 

[Xandros]

I just mean it gets noticeable enough after the 3rd layer. I print A4 size for now, and when I register the negative after 2 completed layers, if I register top left corner, then look at the bottom right corner there's about 1 millimeter off. So that would be about 1mm off for 366mm (diagonal), so that's about 0.27% shrinkening. I would say that I have the feeling that it keeps shrinking a bit more with each layer, but less and less, the first layers seems to make it the most noticeable. Does this make more sense to you ? I should have been more precise..