Tempera Panel Painting/Gesso
Ian Johnson
shield constructed and painted using period techniques. Medieval
shields were decorated in the same manner as wood panels with tempera
paints on a gesso ground, and the device sometimes molded in the
gesso.
I would like to do this from the ground up, so to speak, making my own
size, gesso, and paint. I'm thinking of using this as a learning
experience to maybe go on to traditional panel painting, maybe
eventually do an icon with gilding, etc.
I would like to know if anyone has had any experience doing this. Are
there any guidelines for mixing tempera and pigments? Has anyone ever
tried making gesso? I have some good written sources, but advice from
someone who has been there would be helpful as well.
Iain McClennan
BBrisbane
Please contact Master John the Artificer at < jarti...@aol.com >.
Master John is a strong leader of the 'from the ground up' concept and an
expert at the manufacture of artists pigments, tools, and such. He will
certainly know how to make gesso and will be able to aid you throughout
your project.
Lord Brendan Brisbane
MoAS to the Principality of AEthelmearc
BBrisbane
To the Gentle seeking to make a period shield. Sometime ago, I know
not how far, there was a TI that presented a good article on doing what
you intend. I would suggest you might find someone with a large
collection of TIs and scann them? --- Lord Brendan
Kate was here
to try this myself. Slaking the plaster takes weeks. I did mine
in a bucket in the bathtub (my housemate still hasn't forgiven
me). The directions in Cininni and Thompson work and well too.
When you make your gesso sotile, substitute zinc oxide or
titanium oxide for lead white in the recipe. The substitution
works as well as the lead white, and won't poison you, your pets
or your loved ones. Armenian bole is available from Pendragon and
other specialty calligrphy supply houses in the US; it's not even
all that expensive. Rabbit skin glue is available from good art
or calligrphy supply firms; fish glue is harder (in my experience)
to get.
If you have a compost pile and means to keep small children and
animals out of it, the dutch process for making lead white is easy
and fairly safe upto the point where you uncap your jar and take
it out. The thought of anyone grinding their own lead white makes
my skin crawl, because lead pigment dusts are the primary culprits
in lead poisoning. Please please please cheat and use a
substitute! (I've been doing toxic substances professionally for
almost a decade: lead is bad stuff - there's a reason we took it
out of gasoline...)
Please do not contemplate making your own vermillion either.
If there's one thing worse than lead, it's mercury. Can you say
Minamata disease? Yuck! Ick! Gack! Please cheat and use
something less lethal to you and your loved ones! Mercury is the
only toxic metal for which there is NO chelation "cure" for
removing it from human tissue.
When it got time to build up layers of gesso on wood, use a thick
lamination of wood or wet the back side if the water in the gesso
mix seeps deeply into the wood. Not to have the wood all the way
wet uniformly is to invite bad warping (this is the unfortunate
voice of experience here).
For making the laminations of wood, find a place where no one else
will be around to smell the cheese glue in all its glory.
Unchanged cat boxes smell better.
Get a glass plate and meuller for mixing your pigments and your
gum water (well, I use gum water becuase I've had the best luck
with it). You can buy gum water pre-made from winsor-newton or
you can make it up from scratch. There's little difference
between the two; made-from-scratch has the added advantage that
you can directly control the strength of the brew. The
disadvantage is the mess.
I've made the assumption that you have Cininni and both Thompson
books (all avail from Dover) at hand, as well as Divers Arts
(Theophilous) and Vasari on Technique (also from Dover, I
believe). Mayer's _Artist's Handbook_ is an essential modern
reference as to old materials and modern substitutes. The
Calligraphers Handbook, editted by Child, has some surprisingly
good recipes in it which are pertinent to your project. Get one
of the several manuals on artist safety and read it before doing
anything.
Ian Johnson
> I have some thoughts to share, having been perverse enough
> to try this myself. Slaking the plaster takes weeks. I did mine
> in a bucket in the bathtub (my housemate still hasn't forgiven
> me). The directions in Cininni and Thompson work and well too.
How does slaked plaster differ from normal plaster? BTW, I found
slaked at Sinopia's www page- their price and a month's effort balance
out.
> When you make your gesso sotile, substitute zinc oxide or
> titanium oxide for lead white in the recipe Rabbit skin glue is available from good art
> or calligrphy supply firms; fish glue is harder (in my experience)
> to get.
I'm still at the gesso grosso stage. I finally got a mix of plaster
and size (1/10 gelatin/water) that I can work with, but it has been
cracking a bit as it dries. I'm doing a buckler as a test project and
one that I wouldn't mind beating with a sword to see what happens. By
the time I get the gesso technique worked out, it's going to be plenty
heavy.
Have you played with making raised designs in gesso? What did you use
for scraping and smoothing?
> Please do not contemplate making your own vermillion either.
I considered buying vermillion, but it's expensive. Are there any
substitutes that have the same color? Where pigments are concerned,
I'm more interested in authenticity of shade than material.
> When it got time to build up layers of gesso on wood, use a thick
> lamination of wood or wet the back side if the water in the gesso
> mix seeps deeply into the wood.
Thompson and/or Cennini recommends sizing the wood first thing to
close off the pores. Is there still a danger of warping even so?
> For making the laminations of wood, find a place where no one else
> will be around to smell the cheese glue in all its glory.
> Unchanged cat boxes smell better.
Do you have a cheese glue recipe?
> Get a glass plate and meuller for mixing your pigments and your
> gum water (well, I use gum water becuase I've had the best luck
> with it).
What is gum water? Have you tried egg yolk?
> I've made the assumption that you have Cininni and both Thompson
> books (all avail from Dover) at hand, as well as Divers Arts
> (Theophilous) and Vasari on Technique (also from Dover, I
> believe). Mayer's _Artist's Handbook_ is an essential modern
> reference as to old materials and modern substitutes.
I have Ceninni and Thompson, I'll look out for the others.
Thanks,
Ian
Kate was here
Ian and all other good gentles:
>How does slaked plaster differ from normal plaster?
plaster of paris is a a ploymorph of the mineral anhydrite, with
a formula of CaSO4.(1/2)H2O. When you slake it, it takes in
water and cures into gypsum, CaSo4.2(H2O). Since it's in a
bucket while is sets, the presence of excess water prevents the
gypsum from hardening into one large plater block. The end
result is a very fine powder of gypsum. The time involved is
necessary to push the reaction all the way to completion
(normally, some of the original plaster-of-paris remains
unreacted; and because of the law of mass action, the rate of
reaction slows as the concentration of the plaster-of-paris
drops - that's why it takes so long)
Please don't try grinding up gypsum as a substitute.
It has too many impurities.
The trouble with buying slaked plaster is one of quality
control. Making your own is better if you want some control
over the purity of the final product.
>I'm still at the gesso grosso stage. I finally got a mix of plaster
>and size (1/10 gelatin/water) that I can work with, but it has been
>cracking a bit as it dries.
1) make sure that's animal-based gelatine
2) your water to plaster ratio may be screwed up. Too much and
too little water will both cause cracking. Your gesso mix should
be thinker than a milkshake (the real kind, not the MacShake kind)
but thinner than bread dough.
>Have you played with making raised designs in gesso? What did you use
>for scraping and smoothing?
Knives. Lots and lots of knives. I'll not fess up to using
spoons, forks, sandpaper and dental picks.
>I considered buying vermillion, but it's expensive. Are there any
>substitutes that have the same color? Where pigments are concerned,
>I'm more interested in authenticity of shade than material.
Cadmium red is a good color match and loads safer. It's not
harmless; but so long as you don't lick your brush, eat nor drink
when painting, nor store your paints and projects in reach
of pets and children, it's not bad stuff (the best way to get
cadmium poisoning is to smoke cigarettes a few decades). Cadmium
may not be mercury in terms of toxicity, but it's still worth a
heathy respect. It is expensive, as are all the cadmium pigments.
They last longer than the lakes, so the price balances out. (My
original tube of cadmium red is half empty; I bought it 8 yrs ago)
>Thompson and/or Cennini recommends sizing the wood first thing to
>close off the pores. Is there still a danger of warping even so?
Which Thompson book are you referring to? I'm looking at
Thompson's book on tempera painting (and not at his book and the
materials and techmiques of medieval painting), and his recipes
for prepping the wood are alright. (I confess that the other
thing we did wrong was to neglect aging the wood, and in this case
gave verification that haste makes waste.)
>Do you have a cheese glue recipe?
Cininni, p. 68 Use the curds from low-fat cottage cheese, or get
some skim milk, let it sour, and then use the curds. Work it into
the quick lime (CaO) thoroughly. Use it within the hour. The bad
smell is the reaction that cures the glue. Blech!
Avoid the temptation to purchase casein binder from an art supply:
commercial caseins are more soluable and more alkaline that the
real thing you can make at home, that is if you don't get evicted
for the smell...
>What is gum water? Have you tried egg yolk?
Gum water is water mixed with solid gum arabic "crystals."
Yes, I've tried egg yolk. Works well with malachite green,
darkens azurite blue just a smidggin. Yellows and scarlets do ok
with egg yoke. Don't use it with white or the darker reds:
the colors substract and it dries looking somewhat brown.
I use range eggs from friends. The grocery store eggs tend to
make the copper carbonate pigments go brown within a few years
(which will happen if there's too much sulfur in the egg).
For the nasty pigments, I prefer glaire.
I realize I forgot to mention that Thompson put out two books, one
an materials and one on tempera. For your purposes, Thompson's
tempera book will suit you better.
ttfn, Twcs
Ian Johnson
> 1) make sure that's animal-based gelatine
> 2) your water to plaster ratio may be screwed up. Too much and
> too little water will both cause cracking. Your gesso mix should
> be thicker than a milkshake (the real kind, not the MacShake kind)
> but thinner than bread dough.
The first batch I mixed was thick, but didn't go on very smooth. I
think I just didn't grind it in enough. The stuff that cracked was
too thin. Will extra plaster gesso keep in a closed jar, or will it
set up anyway?
Is knox gelatin animal based? Boiling parchment would be cool, but
the scribes would probably hate me for that.
Do you have some idea of the strength of this gesso? I would like to
be able to fight with the shield in the rare dress-up tourney. I
figure normal plaster would crumble under a few blows, does the
gelatin add a significant amount of strength? I was thinking of
molding the gesso grosso, then laying some thin fabric soaked in size
over it to prevent chipping, with several coats of gesso sottile added
on top.
> >Thompson and/or Cennini recommends sizing the wood first thing to
> >close off the pores. Is there still a danger of warping even so?
>
> Which Thompson book are you referring to?
In the Tempera book under the chapter on Cennini's gessos it says to
coat the wood with size then cover it with size-soaked linen. I'm not
too concerned about warping though, since I intend to curve it anyway.
Thanks for the info
Ian
Rick Cavasin
In article <317260...@magic1.org>, Ian Johnson <ijoh...@magic1.org> writes:
|>
|> The first batch I mixed was thick, but didn't go on very smooth. I
|> think I just didn't grind it in enough. The stuff that cracked was
|> too thin. Will extra plaster gesso keep in a closed jar, or will it
|> set up anyway?
|>
|> Is knox gelatin animal based? Boiling parchment would be cool, but
|> the scribes would probably hate me for that.
|>
There are a number of different hide glues available that are based on
animal gelatine. Kremer Pigments (1-800-995-5501) sells a number of different
types. If you dilute the glue with more than the standard amount of water,
you should get a useable size.
As to boiling parchment, a number of bookbinding supply houses sell parchment
clippings/trimmings for making size/glue.
Or you can do what Cennini suggests, and go to a parchment maker (ie. me) and
get some odd bits and shavings, and boil these down to make your size/glue.
I save both the crinkly bits from the edges of the skins as well as the
shavings for people who want to boil them down to make size. While the
crinkly bits work fine, straining out the shavings after boiling could be
problematic (I suspect they would resolve into mush). The Canadian Conservation
Institute uses both for making size, but I don't know how they deal with the
shavings.
um...how many pounds were you after?
Cheers, Rick/Balderik