What is Gesso?

Ned Chaney · Post by **Ned Chaney** » Wed Jan 17, 2001 12:14 pm

I've read several books about arms and armour and this keeps coming up. Last night was the latest. It usually reads something like "His shield was made from three boards of birch covered with gesso and leather and painted". What is, or was, gesso?

Edward

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The way to a man's heart is between the second and third ribs

Templar Bob/De Tyre · Wed Jan 17, 2001 12:35 pm

It's a coating currently used for canvas, consisting of ground shell and gypsum. They used a thick mixture to help with bas-relief on shields.

The Black Prince's shield (over his effigy) is prepared with gilded gesso.

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Robert Coleman, Jr.

The Noble Companie and Order of St. Maurice

Those who beat their swords into plowshares end up plowing for those who don't.

JGraham · Post by **JGraham** » Wed Jan 17, 2001 12:53 pm

You can pick it up at any art supply store - it's with the canvas and paints.

Jim

Templar Bob/De Tyre · Wed Jan 17, 2001 12:57 pm

Yeah...what he said. I meant to point that out...honest!

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Robert Coleman, Jr.

The Noble Companie and Order of St. Maurice

Those who beat their swords into plowshares end up plowing for those who don't.

Lu-shan · Post by **Lu-shan** » Wed Jan 17, 2001 2:19 pm

Historically, it was Plaster of Paris, calcium carbonate (Chalk) or gypsum powder in a glue (hide, hoof, etc) medium. Acrylic gesso is a modern substitute made with polymers.

The other comments are correct, as well

Cheers, Lu-shan

Ned Chaney · Post by **Ned Chaney** » Wed Jan 17, 2001 2:33 pm

So instead of the raised portions of the heraldic device being carved out of the leather they were built up with gesso? Or maybe carved out then built up? How does modern gesso hold up to repeated blows from Rataan weapons?

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The way to a man's heart is between the second and third ribs

Lu-shan · Post by **Lu-shan** » Wed Jan 17, 2001 2:41 pm

<BLOCKQUOTE>quote:<HR>Originally posted by edward atte flynt:
 How does modern gesso hold up to repeated blows from Rataan weapons?
<HR></BLOCKQUOTE>

I would think not at all. Gesso fills in cracks and smooths the surface nicely, but it will break under impact.

Bojei Temur · Post by **Bojei Temur** » Wed Jan 17, 2001 3:29 pm

The modern stuff's pretty durable actually. It's made to go on unsupported canvas. It's fairly indestructable after it's been covered with oil or acryllic paints.

I've repeatedly tested this - my mom's an artist and I can't remember my brother or I ever 'cracking' a painting. Also, my stepson (now 19) and his friends never hurt them when they crashed into the paintings when they were wrestling. Of course, darts will go through them....

I don't know if the period stuff was different or what effect being placed against a solid surface like a shield would have.

Lu-shan · Post by **Lu-shan** » Wed Jan 17, 2001 3:35 pm

Gesso is plenty durable on paintings as a sizing - that is what it is for, and it does a spiff job.

But in the context of heavy relief sculptures, I would not think it would hold up to beihg whacked with a stick. Too thikc and unsupported.

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"I have a magic cat's ass"

Vitus von Atzinger · Post by **Vitus von Atzinger** » Wed Jan 17, 2001 3:58 pm

Gesso can be made much thicker, and was used for moldings and high relief figures on panels and shields in period. I would advise you to purchase Cennini's 15th century treatise, which can be bought from
www.sinopia.com

Ned Chaney · Post by **Ned Chaney** » Wed Jan 17, 2001 9:24 pm

Gesso is plenty durable on paintings as a sizing - that is what it is for, and it does a spiff job.

You mean like a preperation over the wood to prepare it to be painted? So the paint would go on smoother and adhere better? I'm gonna have to get some cause I want my shield to look really cool!

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The way to a man's heart is between the second and third ribs

[This message has been edited by edward atte flynt (edited 01-17-2001).]

Ned Chaney · Post by **Ned Chaney** » Wed Jan 17, 2001 10:05 pm

Been thinking about this all evening and by george I think I've got it!! Canvas stretched over the wood, prepped with Gesso, then Painted with the heraldic device?? I'm gonna try this method. It would cover up the bolt heads that attach the handles. I'm also gonna try cutting my three charges (wolves heads) out of red leather and gluing them on. Whatcha think?

Edward

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The way to a man's heart is between the second and third ribs

IainMcClennan · Post by **IainMcClennan** » Thu Jan 18, 2001 9:34 am

Gesso holds up better than you would think. I made a shield of birch covered with canvas leather and gesso, but first I made a test piece. I made a buckler with a textured gesso background with a sun in gesso relief surrounding the boss. The gesso on the edges quickly chipped away, but the sun on the flat of the shield remained intact. It didn't fail until it began pulling away from the surface of the shield.

If you want to use gesso, I would recommend using it only to model the charges of your device. Use a stronger solution (more glue less plaster), but keep in mind that the stronger it is, the more likely crack will develop when it dries. These can be filled with more gesso later, or you can experiment with a few batches. I made gesso by combining plaster and hide glue (also at art stores). Check out Cennini as Vitus said, and there is also a book on painting wood panels with tempura written in the 1930's that is very good. I don't remember the author, but Thomas sounds right.

Ian

Guy Dawkins · Post by **Guy Dawkins** » Thu Jan 18, 2001 9:48 am

Here is a link to THL Charles Oakleys' shield construction article. He covers a lot of what your asking. http://www.dnaco.net/~arundel/shield_article.html

Lu-shan · Post by **Lu-shan** » Thu Jan 18, 2001 11:37 am

Well Dang, I'll have to try this myself! It would be cool to have relief on a shield.

Lu-shan · Post by **Lu-shan** » Thu Jan 18, 2001 11:42 am

<BLOCKQUOTE>quote:<HR>Originally posted by edward atte flynt:
Been thinking about this all evening and by george I think I've got it!! Canvas stretched over the wood, prepped with Gesso, then Painted with the heraldic device?? I'm gonna try this method. It would cover up the bolt heads that attach the handles. I'm also gonna try cutting my three charges (wolves heads) out of red leather and gluing them on. Whatcha think?

Edward
<HR></BLOCKQUOTE>

Use hide glue for the leather, and glue it on before you paint. That should ensure the charges stay on fairly well. (in theory)

Vitus von Atzinger · Post by **Vitus von Atzinger** » Thu Jan 18, 2001 3:13 pm

The book that Ian is referring to is by Daniel V. Thompson. It is called "The Practice of Tempera Painting".
I once molded my device out of carpenters wood filler. It took forever but it was tough as nails. In period, a wood surface that was to be painted usually had a piece of cloth glued over the entire surface before the gesso was applied. Just remember, if you are going to use ground pigments that are tempered with egg, you will have alot of trouble getting your paint to adhere to acrylic gesso. Also, get a breathing mask.
My new shield for the Pennsic Pas will be covered in tooled 24 carat gold leaf! Muhahahaha!
Seriously guys, Ian has made some of the most beautiful shields anywhere- his methods are true and get great results.
-V

Hushgirl · Post by **Hushgirl** » Thu Jan 18, 2001 3:27 pm

What about weight?

Galileo · Post by **Galileo** » Sun Jan 21, 2001 6:29 pm

Gee, and here all this time I thought it was a response...

"Wanna go to the mall?"

"I gesso"

G--

Hushgirl · Post by **Hushgirl** » Mon Jan 22, 2001 12:30 pm

How much weight does it add? How does it affect the balance?

Vitus von Atzinger · Post by **Vitus von Atzinger** » Mon Jan 22, 2001 3:08 pm

The gold or the gesso?
-V

Hushgirl · Post by **Hushgirl** » Mon Jan 22, 2001 4:19 pm

The gesso. I mean, of course it would depend on how much you used, but on a given, extant sheild, how much did it add for the given application?

IainMcClennan · Post by **IainMcClennan** » Tue Jan 23, 2001 1:07 am

For my buckler, I think I ended up using a 2lb bag of plaster. Both sides of the shield were covered though, since I was using it to learn. If you just model the charges, it shouldn't be much.

Ian

Hushgirl · Post by **Hushgirl** » Tue Jan 23, 2001 6:38 am

T-Bob's sheild is a lot bigger than a buckler. T-Bob, you reading this?

Lodhur · Post by **Lodhur** » Wed Jan 24, 2001 2:38 pm

I used gesso mixed with some elmer's glue on my cuir bouilli scales. Especially on scales that I over-cooked. I has helped, some. None of the gesso has come off, even though I've washed the whole suit in the washing machine. I also used it to stiffen the canvas backing for the scales. Adds strength & prevents fraying in places where I had to pierce the canvas.