Re: brush vs tray size for gum
Sandy, So you are rolling the rod not pushing it along. As I recall the illustrations I've seen for "puddle pushers" had handles so would not roll. I would have thought that the rolling motion would pull up the gelatin behind the rod. But apparently not. Thanks for the info. Jack > From: Sandy King <sanking@clemson.edu> > Reply-To: alt-photo-process-l@usask.ca > Date: Tue, 03 Oct 2006 00:22:48 -0400 > To: alt-photo-process-l@usask.ca > Subject: Re: brush vs tray size for gum > > Jack, > > I use a 1"-12, 1/2" diameter rod for coating > paper for carbon final support. This leaves a wet > coat height of about 0.4mm. > > Before coating the rod is placed in a tube with > hot water at about 130ºF. I spread the gelatin > solution over the paper, usually about 22"X29", > and quickly even the solution by hand or with a > brush. Then, I roll the rod over the paper. As > the hot rod passes over the surface of the paper > it levels the gelatin coating, and at the same > time, dissipates bubbles. I add the hardener to > the paper just before coating, as Kerik described. > > The solid metal rod holds heat much longer than > glass, either tubes or solid, and is much more > effective for my use. I suspect the same would be > true for coating papers for gum printing. > > > > Sandy King > > > > > > > > > > > > > At 4:53 PM -0400 10/2/06, Jack Brubaker wrote: >> Sandy, >> >> What size rod and what thread do you use? >> >> Jack >> >>> From: Sandy King <sanking@clemson.edu> >>> Reply-To: alt-photo-process-l@usask.ca >>> Date: Tue, 26 Sep 2006 17:42:26 -0400 >>> To: alt-photo-process-l@usask.ca >>> Subject: RE: brush vs tray size for gum >>> >>> >>> I also size papers for gum using 3-5% solutions and adding just a bit >>> of Formaldehyde to the solution just before coating. I used to use a >>> brush, but this caused a lot of bubbles. I switched to a threaded >>> rod, which I heat before running it over the solution, and this >>> completely eliminates the bubble problem because the warm rod >>> dissipates the bubbles on contact. This is a technique that I adopted >>> from coating carbon tissue. >>> >>> I am using more solution per given paper area than would be required >>> for gum printing, but I think this should not matter in practice. >>> >>> Sandy >>> >>> >>> >>> >>>> Carmen, >>>> >>>> The largest print I've sized is 20x24. But, if I was going to do 22x30, I >>>> would make a 22" glass coating rod and apply the sizing with the rod, then >>>> use a brush to fix any areas that were either too thin or too thick. This >>>> makes the process go very quickly so the gelatin doesn't have the chance to >>>> harden. I would also use formaledehyde rather than glyoxal to prevent >>>> yellowing. When using a glass rod, first place a towel on the table >>>> underneath the paper. This will greatly help keep the rod in good contact >>>> with the paper, especially for larger prints. I would guess about 30 ml of >>>> 3% gelatin with 18 drops of hardener would do it. >>>> >>>> Kerik >>>> www.kerik.com >>>> >>>> >>>> Original Message: >>>> ----------------- >>>> From: Carmen Lizardo carmenlizardo@yahoo.com >>>> Date: Tue, 26 Sep 2006 12:51:12 -0700 (PDT) >>>> To: kerik@kerik.com, alt-photo-process-l@usask.ca >>>> Subject: RE: brush vs tray size for gum >>>> >>>> >>>> Dear Chris and Kerik, >>>> I would love to brush size my paper, specially because >>>> use a full sheet of 22x30 inches when I print, and you >>>> could only imaging how long that takes and how much >>>> gelatin I need, but I can't seem to be able to get an >>>> even coat, and mixing glyoxal and gelatin together is >>>> out because I have to able to rise it off the gelatin >>>> to prevent yellow stains. Of course when I used Glut, >>>> it was from black magic and that did not work. I also >>>> felt it in ky eyes and throat and i not even the >>>> sensitive type. I am willing to try again, maybe with >>>> a different glut?? Any pointers that you can give me >>>> with the brushing?? I was thinking that it had to do >>>> with the size of my paper. The gelatin gets hard >>>> before I have time to cover the whole 22x30 sheet. >>>> Thank you kindly, >>>> Carmen >>>> >>>> --- "kerik@kerik.com" <kerik@kerik.com> wrote: >>>> >>>>> Chris, >>>>> >>>>> I agree that tray sizing is a lot of mess and hassle >>>>> for no substantial >>>>> benefit. Plus, why do the sizing in 2 steps when it >>>>> can be done in one? I >>>>> use either a glass rod (puddle pusher) and/or a >>>>> brush. I add the hardener >>>>> (formaldehyde in my case) to the sizing just before >>>>> sizing each print. >>>>> Three drops of formaldehyde and 5 ml of 3% sizing >>>>> easily does an 8x10 to >>>>> 11x14 print. In these tiny amounts, exposure to >>>>> formaldehyde (or whatever >>>>> hardener one uses) is minimal. I get very even >>>>> sizing this way. A little >>>>> bit of curl to the paper, but nothing that causes >>>>> any problems. >>>>> >>>>> I tried B.M. glut and did not like the results. It >>>>> resulted in slower >>>>> development and considerably more staining than with >>>>> formaldehyde. >>>>> >>>>> As for sizing with unhardened gelatin, that sounds >>>>> like another in a long >>>>> line of T King's erroneous hyperboles. >>>>> >>>>> Speaking of gum, I taught a gumover workshop in >>>>> Philladelphia this past >>>>> weekend for www.projectbasho.org. On sunday it was >>>>> 80 degrees F and 82% >>>>> humidity in the darkroom. That's the first time I've >>>>> printed gum in >>>>> sauna-like conditions and it created some hassles >>>>> with very slow >>>>> development and the need to intervene with some >>>>> brute force measures >>>>> (brushes, fingernails, sandpaper). Anybody have >>>>> similar problems printing >>>>> gum in high humidity? The conditions seemed to >>>>> cause problems with the >>>>> sizing in particular because development was much >>>>> closer to normal when I >>>>> did a single coat of gum on unsized paper right out >>>>> of the plastic bag. I'm >>>>> speculating that the humidity either prevented the >>>>> gelatin from hardening >>>>> completely or it allowed the gum solution to soak >>>>> into the sizing a bit >>>>> rather than sitting on top. Despite the problems, I >>>>> believe a good time was >>>>> had by all. Although I always want things to go >>>>> smoothly during the >>>>> workshops, it's good for the students to learn how >>>>> to deal with problems >>>>> when they come up. >>>>> >>>>> Kerik >>>>> www.kerik.com >>>>> >>>>> >>>>> Original Message: >>>>> ----------------- >>>>> From: Christina Z. Anderson zphoto@montana.net >>>>> Date: Tue, 26 Sep 2006 08:08:22 -0600 >>>>> To: alt-photo-process-L@usask.ca >>>>> Subject: brush vs tray size for gum >>>>> >>>>> >>>>> Hi All, >>>>> This weekend was time for sizing paper, and since I >>>>> was doing small sizes >>>>> (11x14's) I decided to tray size instead of brush >>>>> size to see if it had any >>>>> added benefits to brush sizing. >>>>> >>>>> I was sizing with gelatin glutaraldehyde as usual. >>>>> I did use a piece of it >>>>> right away, same day, and had no problem with the >>>>> sizing not being hardened >>>>> and producing "magenta squares" as did Carmen. >>>>> However, I was using glut >>>>> that I bought from a medical supply house (now >>>>> available at the >>>>> Photographer's Formulary) and not Black Magic. The >>>>> gelatin on my paper was >>>>> not slimy in any way so I know it was hardened. I am >>>>> still not sure why >>>>> Carmen got that problem, and am wondering about the >>>>> suitability of Black >>>>> Magic, therefore, with its added sulfite. It sounds >>>>> like the same result I >>>>> had when I tried Terry King's advice to use >>>>> unhardened gelatin and got >>>>> black >>>>> squares. >>>>> >>>>> With tray sizing and cautions with glut, I gelatin >>>>> sized the paper first, >>>>> and then the next day I soaked the sized paper >>>>> OUTSIDE in a tray of 50ml >>>>> glut to a gallon of water. That worked well, but I >>>>> would only tray size if >>>>> the hardening part could be done outside to minimize >>>>> fumes produced by the >>>>> surface area of a whole tray of hardener, whatever >>>>> type--glut, gly, >>>>> formaldehyde. (When I brush size I keep the solution >>>>> capped inside a >>>>> thermos >>>>> and pour out a cup at once.) The gelatin paper went >>>>> in "slimy" feeling, and >>>>> went out unslimy. >>>>> >>>>> The paper works fine but I learned a couple things: >>>>> paper tray sized with >>>>> gelatin will sink to the bottom, not float as does >>>>> brush sized paper >>>>> (except >>>>> Arches) so if I am going to leave the paper soaking >>>>> for a while it needs to >>>>> be face up. I learned that the hard way. Back to >>>>> floaters and sinkers, Mark. >>>>> >>>>> The paper does curl less than brush sized, but it >>>>> doesn't seem worth the >>>>> added trouble of trays. This is the only benefit I >>>>> can see. Oh, maybe more >>>>> evenness of sizing? I don't know this one >>>>> yet...will have to print all >>>>> papers. >>>>> >>>>> My husband set up an ingenious "clothesline" for >>>>> me--a rung ladder on its >>>>> side has plenty of hanger-ready rungs. >>>>> >>>>> I learned another thing the hard way: I printed 4 >>>>> prints on the unsized >>>>> but >>>>> shrunk paper with a cyanotype layer, put the paper >>>>> through the hot gelatin >>>>> sizing process and didn't THINK that the >>>>> 140-whatever degree gelatin would >>>>> shrink the paper even more and make registration a >>>>> B---H but you bet it >>>>> did--warped and shrunk. Luckily only 4 prints >>>>> ruined. DUH. Or, as Clay >>>>> says, >>>>> DOH. >>>>> >>>>> The bottom line is that brush sizing is sooo much >>>>> easier and works well and >>>>> uses way less gelatin--I sized 24 11x14s with a a >>>>> liter of 3%, and normally >>>>> I can do that many 16x20s with the same. I don't >>>>> think even with small >>>>> sizes >>>>> I would tray size... >>>>> >>>>> That's all my truly exciting weekend experience! >>>>> >>>>> Chris >>>>> CZAphotography.com >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> -------------------------------------------------------------------- >>>>> mail2web - Check your email from the web at >>>>> http://mail2web.com/ . >>>>> >>>>> >>>>> >>>> >>>> >>>> __________________________________________________ >>>> Do You Yahoo!? >>>> Tired of spam? Yahoo! Mail has the best spam protection around >>>> http://mail.yahoo.com >>>> >>>> >>>> >>>> -------------------------------------------------------------------- >>>> mail2web - Check your email from the web at >>>> http://mail2web.com/ . >>> >>> > >
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