RE: "speckling" v "staining "

Hi Don,

FYI, your response came to me, rather than to the list, but I'm sending this
to the list. Yes, I use 37% formaldehyde. That seems to be a standard
concentration. I got mine from a local pharmacy who sold me a pint after I
explained what I was using it for. Cost about $15.

As for the respirator and cartridges, I got them fom Lab Safety Supply. Here
is the one I bought:
http://www.labsafety.com/store/product_group.asp?dept_id=1456&cat_prefix=5WA

You'll find the formaldehyde cartridges here:
http://www.labsafety.com/store/product_group.asp?dept_id=1461&parent_id=4287
2

And thank you for the kind words about my work. I completely agree about the
desire for a clean, safe, consistent workflow. This approach works for me.

Kerik

> -----Original Message-----
> From: Don Bryant [mailto:dstevenbryant@mindspring.com]
> Sent: Tuesday, September 13, 2005 8:05 PM
> To: kerik@kerik.com
> Subject: RE: "speckling" v "staining "
>
> Kerik,
>
> Thanks for the informative reply. It sounds very tidy.
>
> Where do you purchase your formaldehyde? Bryant Labs sells a
> 37% solution in small quantities, is thisthe concentration you use?
>
> I particularly like the approach to minimizing the exposure
> to formaldehyde.
> Where did you locate your respirator?
>
> For those of you that haven't seen Kerik's gums and gum-overs
> that are ever so smooth and lush. Not a trace of grit or grain.
>
> It is interesting to read about all of the variations used by
> different folks here. I might reiterate that my goal for gum
> printing isn't to discover the holy grail of sizing but
> rather a clean, safe consistent work flow. I'll keep trying.
>
> Don
>
>
> -----Original Message-----
> From: Kerik [mailto:kerik@kerik.com]
> Sent: Tuesday, September 13, 2005 1:10 AM
> To: alt-photo-process-l@sask.usask.ca
> Subject: RE: "speckling" v "staining "
>
> Don,
>
> Admittedly, I'm a little tired of the discussion, but FWIW,
> here's my 2 drachmas on the sizing issue:
>
> I size and harden using Livick's approach (at least I think
> that's where it came from). I make up about 150 ml gelatin
> size, depending on how many sheets I'm going to size. I
> usually use a 3% strength of 250 bloom gelatin.
> I heat it to ~130 to 140 degrees F (55 - 60 degrees C) on a
> small coffee mug warmer. This device keeps the sizing from
> getting too hot (which may or may not be a problem, but I'd
> rather not boil it). In order to reduce bubbles in the
> solution and the resulting gelatin "sparklies" on the print,
> I add Everclear to the sizing solution at a ratio of about 1:20.
>
> For a 14"x17" print I measure out about 10 ml of sizing, then
> I add the hardener to that. I prefer formaldehyde over
> glyoxal because I've had the yellowing issue with glyoxal,
> and enough has already been said about that.
> And I've not seen any hard evidence that glyoxal is a safer
> compound than formaldehyde. Lack of evidence is not proof.
> Formaldehyde is used much more widely, so it's health effects
> have been studied in much more detail than glyoxal. And the
> fact that glyoxal doesn't smell means that you don't really
> know when you're being exposed to its vapors, which may or
> may not be harmful. Both compounds work equally well as
> hardeners in my experience.
>
> I add the hardener at the rate of 1 ml per 1.5 gm of gelatin.
> This reduces to approximately 6 drops per every 10 ml of 3%
> size. I then coat the paper with sizing using a glass rod
> (aka puddle pusher) followed by a little hake brushing, if
> necessary. Using the formaldehyde in such small quantities
> results in very little odor in the room and very little
> chemical exposure for me. As a precaution, I use an
> air-purifying respirator with cartridges designed for
> formaldehyde when I'm sizing my paper. But, the next day
> after sizing and letting the paper dry in my darkroom, I
> detect no formaldehyde odors.
>
> I work mostly with Fab. Extra White and get no staining or
> speckling problems. I also use Rives BFK and Whatman's
> watercolor. While BFK can be susceptible to some
> staining/speckling, this is a rare occurrence for me.
>
> I've not tried chrome alum or glut. I'm from the "if it ain't
> broke, don't fix it" school, so haven't found the need to
> fiddle with those compounds.
> For me, this is a very simple, reliable approach to a smooth
> and even sizing with very little chemical exposure. If you
> pump your own gas or drink chlorinated water, I suspect that
> your exposure to potential carcinogens is many times greater
> than sizing paper in this way.
>
> All that being said, USE THESE CHEMICALS AT YOUR OWN RISK AND
> USE THE PROPER PERSONAL PROTECTIVE EQUIPMENT. One of Clay's
> mean lawyers told me to say that. :-)
>
> Kerik Kouklis
> www.kerik.com
Received on Tue Sep 13 23:37:11 2005