Interesting Cennini references

http://www.noteaccess.com/Texts/Cennini/index.htm

Section one
Chapter XVI

 "get a leaf of druggists' glue, not fish glue,"

Chapter XXXI

"When you have got this done, take a little white lead well worked up with gum Arabic."

Section three

"Then, when you want to work, remember first to make this plaster quite uneven and fairly rough."

Section 5

"There is one size which is made of cooked batter, and it is good for parchment workers and masters who make books; and it is good for pasting parchments together, and also for fastening tin to parchment. We sometimes need it for pasting up parchments to make stencils. This size is made as follows. Take a pipkin almost full of clear water; get it quite hot. When it is about to boil, take some well-sifted flour; put it into the pipkin little by little, stirring constantly with a stick or a spoon. Let it boil, and do not get it too thick. Take it out; put it into a porringer. If you want to keep it from going bad, put in some salt; and so use it when you need it"

Section 5

How Goat Glue is Made, and How it is Tempered; And How many Purposes it will Serve.
Chapter CVIIII
"And there is a glue which is known as leaf glue; this is made out of clippings of goats' muzzles, feet, sinews, and many clippings of skins. This glue is made in March or January, during those strong frosts or winds; and it is boiled with clear water until it is reduced to less than a half.[102] Then put it into certain flat dishes, like jelly molds or basins, straining it thoroughly. Let it stand overnight. Then, in the morning, cut it with a knife into slices like bread; put it on a mat to dry in the wind, out of the sunlight; and an ideal glue will result. This glue is used by painters, by saddlers, and by ever so many masters, as I shall show you later on. And it is a good glue for wood, and for many things. We shall discuss it thoroughly, showing what it may be used for, and how, for gessos, for tempering colors, making lutes, tarsias, fastening pieces of wood and foliage ornament together, tempering gessos, doing raised gessos; and it is good for many things."

A Perfect Size for Tempering Gessos for Anconas or Panels.
Chapter CX
"And there is a size which is made of the necks[103] of goat and sheep parchments, and clippings of these parchments; these are washed [p. 67] thoroughly, and put to soak a day before you put them on to boil. Boil it with clear water until the three parts are reduced to one. And when you have no leaf glue, I want you just to use this size for gessoing panels or anconas; for you cannot get any better one anywhere."


A Size Which is Good for Tempering Blues and Other Colors.
Chapter CXI
"And there is a size which is made from the scrapings of goat or sheep parchment. Boil them with clear water until it is reduced to a third.[104] Know that it is a very clear[105] size, which looks like crystal. It is good for tempering dark blues. And apply a coat of this size in any place where you have happened to lay in colors which were not tempered sufficiently, and it will retemper the colors, and reinforce them, so that you may varnish them at will, if they are on panel; and blues on a wall the same way. And it would be good for tempering gessos, too; but it is lean in character, and it ought to be rather fat for any gesso which has to take gilding."

Section 5
To Make a Glue out of Lime and Cheese. 
Chapter C XII
"Ends the Fifth[107] Section of This Book.
There is a glue used by workers in wood; this is made of cheese. After putting it to soak in water, work it over with a little quicklime, using a little board with both hands. Put it between the boards; it joins them and fastens them together well. And let this suffice you for the making of various kinds of glue."

Section 6

on using sheep size, 

"any sort of work which you have to gesso, using a large soft bristle brush. 

Then let it dry. [p. 69] Next take some of your original strong size, and put two coats over this work with your brush; and always let it dry between one coat and the next; and it will come out perfectly sized."

How You May Gesso with Gesso Sottile Without Having Gessoed with Gesso Grosso First.
Chapter CXVIII
"Furthermore, it is all right to give any small-sized and choice bits of work two or three coats of size, as I told you before; and simply put on as many coats of gesso sottile as you find by experience are needed."

Leather Helm Crest: Part 12 Applying Gesso grosso

Here is what Cennini suggests you do to apply gesso to the leather structure.

1. size it two or three times
Done.

2. mix gesso grosso and lay it on in a thick paste, modelling it to the animal shape needed.
Done.

3."This done, take some gesso grosso ground with size, liquid and flowing, on a brush, and you lay it three or four times over this crest with a brush."
When I had moulded the gesso grosso paste onto the leather, I then mixed water with the remaining paste in the bowl and painted it over the damp gesso. It smoothed out the rougher lumps and filled any splits that had formed while the leather flexed. I was not going for a smooth finish, as I wanted to replicate a scruffy, hairy surface.

4. "Then, when it is quite dry, scrape it and smooth it down, just as you do when you work on panel."
I used some sculpture tools to remove any lumps and smooth the surface a little.

5. "Then, in the same way, as I showed you how to gesso with gesso sottile on panel, in that same way gesso this crest. When it is dry, scrape it and smooth it down;"
I applied a layer of gesso sottile with a brush, but made it pancake batter thickness. I think this is much thicker than was intended. Again, I did this so the plaster would 'catch' as it dried and pull into a textured surface to give more of a look like a wavy, bumpy coat of fur.

To make a smooth item, I would mix new gesso grosso immediately after adding the rough layer, making this second, smaller lot with less dry ingredients in the water. I would apply a thin coat with a brush, let it dry, mix a new batch, apply it etc., until there were three or four layers. I would use a rough cloth to rub down the damp gesso grosso where needed. I would also make my layer of gesso sottile much more aqueous and spend time 'polishing' the dry surface with a cloth on a chock.

http://www.noteaccess.com/Texts/Cennini/index.htm

Leather Helm Crest: Part 8 Tow

In returning to an old question I had asked about tow, Cennini has the following to say on preparing gesso grosso:

'CLXIX How to Model Crests or Helmets.[211]
(after making the leather base)... Then take some of the regular size for gessoing, and size it two or three times. Then take some gesso grosso ground with size, and mix in some beaten tow, and get it stiff, like a batter; and put on this gesso, and rough it in, giving it any shape of man, or beast, or bird, which you may have to make, getting it as like as you can. This done, take some gesso grosso ground with size, liquid and flowing, on a brush, and you lay it three or four times over this crest with a brush.

1.    "...regular size for gessoing..."   As discussed in an earlier post, rabbit hide glue was not listed as the most common in use during this time period. It is, however, the most readily available form now. I will use it for this project and investigate other alternatives for future projects, to compare results.

2.    "...size it two or three times..." This could mean 'apply hide glue size to the outside of the leather base in two or three coats.' We often apply a coat of glue as a sealer to woodwork or leatherwork projects, to give better coverage of outer coats of paint. This may help to attach the plaster layer.

3.   "...Then take some gesso grosso ground with size..." We are going to use commercially available Plaster of Paris for our gesso grosso base. Since our plaster comes pre-ground in powdered form, rather than in blocks like Cennini had to deal with, we can go right ahead and mix in some powdered hide glue. He does not provide quantities or ratios. The text only implies that the size proportion is smaller than the plaster proportion.

4.   "...and mix in some beaten tow..."   I have found a few relevant descriptions for tow.

The Free Dictionary website says 

"n. Coarse broken flax or hemp fiber prepared for spinning.... ...[Middle English, possibly from Old English tow-, spinning (in tow-cræft, spinning craft, spinning)."

Word Reference.com says 

"tow /təʊ/    N

1. the fibres of hemp, flax, jute, etc, in the scutched state
2. synthetic fibres preparatory to spinning

Etymology: Old English tōw; related to Old Saxon tou, Old Norse tō tuft of wool, Dutch touwen to spin"

Dictionary.com says

"tow

2  [toh]  noun

1.

the fiber of flax, hemp, or jute prepared for spinning by scutching.

2.

the shorter, less desirable flax fibers separated from line fibers in hackling...

...Origin:  1300-1350; Middle English; 

Old English tōw-  (in tōwlīc  pertaining to thread, tōwhūs  spinning house); 

akin to Old Norse tō  wool

tow

3  [toh] noun Scot.

a rope.

Origin: 1425-1475; Late English (Scots);

Old English toh-  (in tohlīne  towline); cognate with Old Norse tog towline."

This suggests that if I take some rope made from the most common material of 1440, being either flax, hemp or jute, and cut very small fibres up to mix into the plaster, I can use this to "...mix in some beaten tow..." I suppose it would be possible to use unspun flax or jute from another source, too.

This method is supported by the composition of an extant bird crest. This bird is listed as being "...constructed of gesso and coarse fibre, probably jute, over a hardened sculpted leather core..." 
http://www.invaluable.com/auction-lot/cimier-heraldique-pour-grand-heaume-de-tournoi,-40-c-ee0776023c

So, I shall mix some finely chopped jute rope and powdered hide glue into some Plaster of Paris to make gesso grosso, and then paint the thick paste on to the leather form. It finally makes sense!

Paint colours according to Cenninni

I am getting towards the painting stage of my first helm crest so it is time to start thinking about pigments. I have some ready ground pigments to mix into tempera paints and other forms of decoration, but want to check out what Cenninni has to say on the subject.

There is a long list of colours that Cennini instructs his readers to mix and use in specific styles of images. I like reading about the words he uses to describe different colour beards - ruddy, russet, black.

"Chapter XXXVI 

Know that there are seven natural colors[23], or rather, four actually mineral in character, namely, black, red, yellow, and green; three are natural colors, but need to be helped artificially, as lime white, blues--ultramarine, azurite[24]--giallorino"

He lists violet, blue, green, purple, 'ocher', ash grey, greenish grey, red and black made from a combination of lac, ultramarine blue, orpiment, pink, flesh colour, vermilion, red lead, white lead, verdigris, indigo, hematite, lime white, terre-verte, charcoal, malachite, turnsole, black, giallorino, cinabrese, sinoper, ocher, and azurite mixed with lye, water, egg yolks, egg whites, gum or size.

"This Shows you the Natural Colors, and How you Should Grind Black. 

Chapter XXXVI "

To find out the Cenninni's recommended method for mixing black relies on the purpose. He says to mix it on a hard flat stone using another, rounded stone. Amusingly, Cenninni says that if you were to grind it for a year, it would only improve the depth of the colour - I have an image in mind of a team of apprentices working around the clock, trying to beat the boredom. Once ground, it is to be stored in a pot of water with a dust cover over the top. He talks of using burnt peach stones, vine twigs and almond shells, as well as a black stone.

I will need a decent volume of both white and black paint for the badger crest. Hopefully the weather will stay good so I can work on it some more tomorrow.

Leather helm crest: Part 6 Preparing gesso sottile

About a week ago, I started to saturate some plaster of Paris to make gesso sottile. This is the second layer of gesso that Cennino Cennini recommends for the outside of a helm crest. In an earlier post I explored the chemical composition of gesso. Gesso sottile is a super hydrated version of plain plaster of Paris. By soaking the plaster, you are allowing it to take on more H2O (water), giving it the desirable property of a slower drying time. This means we will be able to add the final sculpting touches with more care.

Since this is the first time I have used plaster in this way, to sculpt rather than to make moulded objects, it is all a learning experience. I have no idea how well the plaster will stick to the leather, or how well the second layer of plaster will stick to the first, or how the paint will need to be applied. It will also be the first time I have made pigment based medieval paints. There will have to be some test pieces very soon...

Cennini suggests leaving your plaster to soak for 30 days, changing the water to ensure it remains clean. Other sources say this method is inexact - but it is the best evidence I have, closest to my chosen time period, so I have tried this method first. We can always try something else.

To make gesso sottile, I fill a bucket with water and poured plaster in. It is always recommended that you add plaster to water, not water to plaster. When making a gravy or sauce, this produces lumps but for plaster it works well. I mixed it gently and continued to add plaster until it was not absorbed immediately. I covered the bucket with another tub to stop rain, cats, frogs and leaves getting in. Now, we wait.

Leather helm crest: Part 5 Cennini's sand

To attempt Cennini's leather forming method, I have filled the stitched leather structure with wet sand.

In the section marked 'CLXIX How to Model Crests or Helmets.[211]'
Cennini suggests that after drawing up your model design...
"And draw [p. 108] two of them, and sew them together; but leave it open enough on one side so that you can put sand into it; and press it with a little stick until it is all quite full. When you have done this, put it in the sun for several days. When it is quite dry, take the sand out of it ."

Steps
1  "draw two of them" - I have used more than 2 pattern pieces to form a 3D shape. It is possible that Cennini intends that only very simplistic forms are made from the leather with all protuberances, such as ears, chins, arms and legs, being formed from the gesso grosso layer. I chose to go with the second interpretation, which forms more of the final shape from multiple leather pieces, since this design would add a considerable weight of plaster/gesso for final shaping, otherwise. I guess this just means I have more alternatives to try on future crests.





2  "sew them together" - Done







3  "but leave it open enough on one side so that you can put sand into it" - If I were making a full animal to stand on top of a helm, Cennini's method would help make a  fully formed body shape. Since I am using a head as the base structure, it was possible to have a large opening at the base of the neck to fill with sand. I plan to form a leather cap on the crown of the helm, and stitch this to the lower edge of the neck. As I did not want this leather cap to deform from the wet sand or pushing with a stick, I chose to add it after the main structure is dry.

4  "you can put sand into it; and press it with a little stick until it is all quite full"  - Done. I could have used beach sand, but did not want to have to rinse the salt and impurities from it, and some beaches locally are protected by State and National Park. Further more, while recently living in a coastal town, I worked alongside and became good friends with some women who were Indigenous Australians - they have taught me that it is important to seek permission from the local custodians of the land before removing anything, including sand. Buying sand was a compromise because I could not gain permission to take from local beaches, and this at least gave me the possibility that the sand may have come from somewhere with permission. Yes, I am an optimist.

You can see the colour difference from the left image, with the dry leather, to the right image, which is now packed with wet sand. It took a bit of shaping to get the top to sit in an oval. Next time I would make a wooden disc to fit inside the top to hold the shape.


5
"put it in the sun for several days" - Done. I am not sure it will stay seated where I have put it to rest, so I may need to find a way to chock it up without putting pressure on the outside and changing the shape.

6
"When it is quite dry, take the sand out of it ." - Waiting, waiting...

Leather helm crest: Part 4 leather hardening

http://www.britishmuseum.org/explore/highlights/highlight_objects/pe_mla/a/archers_bracer.aspx

This item is made from leather and has been hardened using water, in a technique known as cuir bouilli. I wonder if the wet sand suggested by Cennini can be made to create hardened leather in this way?

Gesso from calcium carbonate vs gesso from calcium sulphate

In my last post, I briefly outlined what gesso was. I am still looking into how it came to be used and why type was chosen over the other. I used the websites listed in the previous post, particularly this e-book, and will refer to it again here.

Calcium Carbonate
Calcium carbonate was typically used in Northern Europe, most likely because this is where significant and accessible deposits were being mined during the middle ages. It is also known as chalk. Chalk is the remains of ancient sea creatures. It can be finely ground and to make chalk whiting. This whiting can be turned into gesso by adding a size.

Calcium Sulphate
Bulian and Graystone say it was typically used around the Mediterranean region, most likely because Bologna and Volterra have large deposits. Jerry Tresser also records that in the 1300s there was a large deposit being mined at Montmartre, near Paris. This most likely accounts for the common name of the refined product: Plaster of Paris.

The mined substance is known as gypsum. This is CaSO4.2H2O [Calcium sulphate dihydrate]

Gypsum was mined, ground up and burned to remove water and any impurities. Tresser says this process also changes the natural gypsum from yellow to white. When this dried product was ground again, it has the adjust chemical composition CaSO4.1/2H2O . It was, and still is, sometimes called Plaster of Paris. This powder is called gesso in Italian.

Gesso was used in 2 ways.
1. Gesso Grosso
CaSO4.1/2H2O + Size
Plaster of Paris, or gesso, was sifted and then moisten it, assumedly with water.

Add parchment size or hide size to this paste to make gesso grosso. This is the first layer Cennini recommends to apply over the leather crest shape. It is fast drying, but this means bulky sculpture protrusions have less time to sag or drip. This makes it a good material for roughing out the shape.

2. Gesso Sottile
CaSO4.2H2O + Size
Plaster of Paris, or gesso, was soaked in water for several weeks
Cennini says to soak it for 30 days. Jerry Tresser points out that this is an imprecise process, as it is not possible to tell when the gesso was been super hydrated. After reading a few other versions of this process, I think Cennini likely chose 30 days as a safe, standard soaking time to ensure the process was completed by this point.

The water is drained off and the paste is set into blocks to dry again. This powder was called gesso di bologna.

Mix it with size to make Gesso Sottile. This is used in the fine finishing layer of Cennini's crest making process. It has the benefit of being slower drying, allowing more time for fine detailing.

What is Gesso , Ground and Size?

Reading Cennini's instructions on making gesso left me confused so I went searching. The best results I found were at Qualitative Study of Cennini's Gesso for Illumination and Wood Coatings: Theory and Practice pp.142-144 The book is available for purchase as a hard copy or e-book. I liked this person's profile and their enthusiasm for the modern version of the process. Here is a summary of my new understanding of the materials and process.

What is a Ground?

When timber or leather are prepared for painting, it is sometimes useful to place a layer of substance that will enhance the surface texture and the appearance of the paint. Gesso is one form of ground. It is a white substance that is painted over the main structure. In the case of crests, Cennini recommends building a structure of moulded leather and applying several layers of gesso as the ground.

What can Gesso be made from?

Sometimes texts simply use the term 'white ground', which is not very specific but is a good umbrella term. The short answer is that there were 2 main substances in use as white grounds, though other less common materials were also suitable.  

Most Common

Whiting    CaCO3 

AKA Calcium Carbonate

- This is available at my local Eckersleys art shop

Plaster of Paris   CaSO4.1/2H2O

Derived from calcium sulphate

*Note* There are several versions of the usable product so I will add detail

This is available at all hardware shops and art shops

Less Common

Kaolin         A2O3.2SiO2.2H2O
Essentially, a clay, but with a wide range of uses and preparations
Synonyms 
- This is available at my local Eckersleys art shop.

Dolomite     CaMg(CO3)2
Magnesium Calcium Carbonate
- I have not seen this for sale but have not really gone looking
*Note* The term dolomite seems to be a synonym for Calcium Carbonate, even though the chemical composition is different.

What is Size?

Size is another word for glue - a very simplified description, but it makes sense in most contexts. Rabbit hide glue, or just 'hide glue', is available online from book making and fine woodworking websites. It comes as orange brown crystal flakes. Cennini recommends making the best size from the "necks of goats and sheep by trimming, washing, soaking and then boiling it," (Thompson, 1960, cited in Bulian & Graystone, 2009, p. 143, linked above). I will have a look at Cennini for the exact quote. This book also mentions two other "historic treatises" by Theophilus and Watin. Both have a preference for animal glue but none mention rabbit skin glue (Souza and Derrick, 1995, cited in Bulian & Graystone, 2009, p. 143). This implies that perhaps we use rabbit hide glue for most of our reconstruction projects simply because it is readily available at the moment, rather than it is readily available because of superior properties.

Using Cennini's methods to make helms?

Here's a slightly terrifying thought: When Cennini says when you are caused to make a crest or helm, his leather moulding process may actually create a SCA legal equestrian helmet.

http://www.noteaccess.com/Texts/Cennini/index.htm
'Whenever you have occasion to make a crest or helmet for a tourney, or for rulers who have to march in state...'
I had really only read the wording about crests, and glossed right over his mention of making helms using the same process.

The SCA Equestrian handbook says:
'A. Equipment Standards: All equipment must be inspected for use prior to engaging in equestrian combat activities.
1. Armor requirements:
(a) Helm.
(1) Helms must be of rigid materials (18-gauge mild steel or equivalent). Fencing masks are acceptable for mounted crest combat use only.
...
B. Glossary.
1. Rigid material: a. Steel of no less than 18 gauge, or aluminum of no less than 1/8-inch (3mm)....
d. Heavy leather (as defined above) that has been hardened in hot wax, soaked in polyester resin (properly catalyzed), or treated in such a manner as to permanently harden the leather.
e. Two layers of untreated heavy leather.'
It also lists:
'2. Non-brittle: Shall refer to material that will not break or shatter upon being subjected to a stiff strike.'
This implies that although a full helm may be made from Cennini's leather method, the gesso layer could be deemed brittle and unsafe by the Kingdom Earl Marshall.

Fortunately for the sane among us, the Lochac Equestrian page recommends nationally recognised modern helmets are worn at all times while riding. Thanks for looking out for us, Lochac. Perhaps Cennini was saying that this process could be used to create a helm and accompanying crest for parades, where the person would be marching or the helm would be on display. I am going with that option for now.

Crests for 3 purposes

Cennino Cennini has this to say about when you may need to make a crest:

'Whenever you have occasion to make a crest or helmet for a tourney, or for rulers who have to march in state...'

This clearly shows that crests were used for both tourneys and for ceremonial purposes. I am going to try to make a ceremonial or parade helm crest from the processes described by Cennini. I would also like to make a crest that will be suitable for combat. Since SCA combat is modified, I will attempt to cater for the two main types where crests may be appropriate - equestrian mounted crest combat and heavy combat. So, that implies I need to investigate up to 3 types of crest.

1: parade crest - 'for rulers who have to march in state'
2: tourney crests for equestrian use - 'a crest... for a tourney'
3: tourney crests for heavy combat - 'a crest... for a tourney'

I want to try the following methods to make the various crests
A: moulded leather covered in plaster and paint, decorated with feathers and spangles
B: moulded leather without plaster, perhaps still painted or details carved into leather.
C: latex moulded foam crest, painted

The methods for B and C are really interchangeable, and there are some other types of crest that could be suitable for both equestrian and heavy combat. Some seem to be made from feathers, which could fit the safety requirements for equestrian use (cause no harm to horses when knocked off and trodden on), and the safety requirements for heavy combat (no plaster pieces to get in combatants eyes, no rigid tall extensions above the helm that could cause neck injuries if struck).

Here are the uses I can see for each kind
A: parade, full Cennini process
- for use by fighters when being presented to the Crown in ceremonies
- fighters, at the start of a tourney in addition to standards/banners
- at demos to make a visual impact
- for riders in formation riding and during Mounted Games (Non-Contact)
- I would loooove to see a tourney where each fighter has a crest and they are all displayed and paraded around the field by pages
B: Moulded leather
- Mounted Games (Contact) Light [Crested Combat]
- Heavy Combat, if you don't mind it getting beaten up
C: Moulded latex or foam
- this kind of crest is already in use for Heavy Combat and Equestrian Mounted Games (Contact) Light [Crested Combat]

Let's have a look at the requirements for each kind of crest.
1: parade crests
- Must look good.
- Not going to be struck, so less safety requirements or need to replace broken parts.
- Gain visual attention and add to overall pageantry

2: Equestrian crest
Taken from http://sca.org.nz/equestrian/rules-forms.html
-'Nationally recognized approved safety helmets are recommended at all times when riding.' Many people may prefer to mount their crest on a modern certified helmet. It means there can be no drilling or changing the helmet to attach the crest.
-Taken from http://www.sca.org/officers/equestrian/pdf/equestrian_handbook.pdf
 '(b) Crests for mounted crest combat.
(1) Crests shall be at least 5-inches in height.
(2) The crest must be constructed so as not to present an undue hazard if a rider should land on it, or a horse step on it.
(3) The crest must be attached in such a way so as to be easily dislodged by a minimal force blow. Velcro or similar methods are recommended. '
-Also taken from http://www.sca.org/officers/equestrian/pdf/equestrian_handbook.pdf
Must be able to be struck by this and not become dangerous or be so destroyed that the owner cries at the thought of having to remake the crest-
'2. Weapon requirements.
(a) Single Handed weapons.
(1) Mounted Crest Combat. "Boffer" weapons are to be used in this activity.
a. Base material shall be schedule 40 ½-inch PVC plastic pipe. Both ends must be capped, but accessible to marshals for inspection’ to the requirement for end caps to the swords.
b. Minimum ½-inch closed cell foam padding over all striking surfaces.
c. Minimum diameter of 1 ¼-inch.
d. If quillions are used they should not extend more than 1 inch beyond the hand when held.
e. Thrusting tips are not allowed in mounted crest combat. '

3: Heavy Combat
On talking to several heavy fighters, marshals and senior marshals it seems that the biggest points that come out of discussing crests are
* Why would you wear something that would get broken?
* Why would you wear a crest at all? This seemed to be a case of there not being a specific requirement for a well known event (such as Tournament of the Thirty) and the disadvantage of having a thing on your head during regular fights seemed to turn people off. The idea came up several times that if other fighters were wearing one, they might be happy to try one too, but until that time it didn't seem worth it.
* The crest would need to be easily distinguishable from the plumes used by Plumed Participants. Crests with feathers could only be used in parade and tourney scenarios. It may be up to the marshallate to allow other forms of crest in wars.
* The plaster shattering could cause a safety risk by getting in combatants eyes
* The people who were interested in using a crest to add pageantry to their game were also willing to drill mounting holes in their helms. Everyone else was mildly horrified.
* People love talking about high power magnets. Some people were willing to put power sources in their helms in order to attach the crests by magnets. Y'all are mad. Very entertaining.
* Typically, the boys did not like the idea of wearing peacock feathers at all. Oddly, most people seemed fine with ostrich and duck feathers. Perhaps they have become commonplace in the SCA.
* A lot of people had heard of the latex foam crests in use in the US and the general sentiment was that the modern construction was not really an issue because they were very durable.
* The crest needs to either be specifically and safely destructible (such as for a specific tourney, maybe where points are gained for targeting the opponents crest) or able to withstand blows of reasonable force from inch and a quarter rattan weaponry. This could mean that the crest is dislodged, which means it doesn't have to survive the full force of the blow. It could also mean that a moulded leather crest might be popped back into basic shape to survive through a tourney.

Using historically authentic methods, materials and processes is of great import to me. The parade crest is to fulfil this desire.

We do play in the SCA, and that brings modern safety requirements and combat rules into the scene. Reality also brings things like cost and availability. The goal of the Royal Artisan project brings another - inspire people. Some people in the SCA will be inspired by an historically accurate, beautiful piece, while others will be keen to make something that is easy to use in combat without needing to reshape, replaster and refeather the thing after every use. I am hoping that by attempting a combination of crests they may be more accessible to the wide range of people we have playing in Lochac today.

The Great Cennini!

http://www.noteaccess.com/Texts/Cennini/index.htm

While his name reminds me of top hats with rabbits and waist coats, Cennino Cennini was actually an Italian man who recorded a great many construction processes during the late middle ages.

Here is what Cennini has to say about making crests:

'CLXIX How to Model Crests or Helmets.[211]
Whenever you have occasion to make a crest or helmet for a tourney, or for rulers who have to march in state, you must first get some white leather which is not dressed except with myrtle or ciefalonia,[212] stretch it, and draw your crest the way you want it made. And draw [p. 108] two of them, and sew them together; but leave it open enough on one side so that you can put sand into it; and press it with a little stick until it is all quite full. When you have done this, put it in the sun for several days. When it is quite dry, take the sand out of it . Then take some of the regular size for gessoing, and size it two or three times. Then take some gesso grosso ground with size, and mix in some beaten tow, and get it stiff, like a batter; and put on this gesso, and rough it in, giving it any shape of man, or beast, or bird, which you may have to make, getting it as like as you can. This done, take some gesso grosso ground with size, liquid and flowing, on a brush, and you lay it three or four times over this crest with a brush. Then, when it is quite dry, scrape it and smooth it down, just as you do when you work on panel. Then, in the same way, as I showed you how to gesso with gesso sottile on panel, in that same way gesso this crest. When it is dry, scrape it and smooth it down; and then if it is necessary to make the eyes of glass, put them in with the gesso for modeling;[213] do modeling if it is called for. Then, if it is to be gold or silver, lay some bole, just as on panel; and follow the same method in every detail, and the same for the painting, varnishing it in the usual way. '

So, he refers to other parts of his writing that tell a student about
*  'the regular size for gessoing'
*  'gesso grosso'
*  'gesso sottile'
*  'bole, just as on panel'
*  'varnishing it in the usual way'
There must be information on these processes in other portions of his text. I will get a-searching.

The phrase 'take some of the regular size for gessoing, and size it two or three times' confuses me. Does the second use of the word 'size' refer to a volume measurement? As in, take some powdered glue and divide/multiply it two or three times. Could that be it? I am still deciphering how the other use of the word size, meaning a glue, often bought as flakes made from rabbit hide.

Or does the text mean 'take some of the regular size...' [the glue you usually use] 'and size [glue] it [the crest model] two or three times' [with two or three layers of glue]

In the section marked 'CLXXIV How to Gild a Stone Figure', Cennini says
'take gesso grosso and size, tempered in the same way you gesso the flat of a panel or ancona, except that I want you to put in, according to the quantity, one or two or three egg yolks; and then lay it over the job with a slice... And apply this gesso two or three times with a slice, and let it dry out thoroughly.
When it is perfectly dry, scrape it and clean it up, just as you do on panel or ancona. Then take gesso sottile or gilders' gesso,[244] and temper and grind this gesso with the same size, just as you do for gesso on panel, except that you must put in a certain amount of egg yolk, not so much as you put into the gesso grosso...'

This implies that that gesso grosso is the coarser, rougher first layer of plaster that is used to make the basic form, while gesso sottile/guilders gesso is the finer or maybe more desirable coloured plaster for the outer layer. The text on making a crest doesn't specifically say to use gesso sottile on crests, however. It appears that he says to mix the gesso plaster and powdered size (glue), but only add egg yolks if forming the gesso over stone, not for forming over a leather base.

The part below of Cennini's text further explains gesso grosso and gesso settile.

'How the Flat or a Panel Should be Gessoed With the Slice with Gesso Grosso.
Chapter CXV
When the ancona is quite dry, take a tip of a knife shaped like a spatula, so that it will scrape well; and go over the flat. If you find any little lump, or seam of any sort, remove it. Then take some gesso grosso, that is, plaster of Paris,[109] which has been purified[110] and sifted [p. 70] like flour. Put a little porringerful on the porphyry slab, and grind it with this size very vigorously, as if it were a color...'

On re-reading this, Cennini is saying to take some dry flakes of the size and some dry plaster and grind them together, as you might when making a paint from ground pigment. Woo! I can do that! I am going to extrapolate further, that the purifying he talks of is some sort of process to remove any impurities like grains of rock or sand. Perhaps means running it through a rough mesh or picking out by hand, before using a fine sifter, like you would with flour. I have not seen metal wire mesh or a sifter from the medieval age. Some cultures use reed mesh in cane frames today, or open weave fabrics pulled taught over a frame or bucket to sift.

'How to Make the Gesso Sottile or Gessoing Panels.
Chapter CXVI
Now you have to have a gesso which is called gesso sottile; and it is some of this same gesso, but it is purified for a whole month by being soaked in a bucket. Stir up the water every day, so that it practically rots away, and every ray of heat goes out of it, and it will come out as soft as silk. Then the water is poured off, and it is made up into loaves, and allowed to dry; and then this gesso is sold to us painters by the apothecaries. And this gesso is used for gessoing, for gilding, for doing reliefs, and making handsome things.'


So that just leaves the question - what is 'beaten tow'?

Plenty to go on with anyway. I will keep digging.