Hardened leather armour 15th century English recipe

[Russ Mitchell]

I'm curious as to how the scabbard butts are different, and whether Gavin's stuff is the same stuff I had tanned a couple years back.
(Honestly, my big problem with the bowl shapes, is how do you keep extra material from screwing the shape?)

[Kilkenny]

I'm curious as to how the scabbard butts are different, and whether Gavin's stuff is the same stuff I had tanned a couple years back.
(Honestly, my big problem with the bowl shapes, is how do you keep extra material from screwing the shape?)

I've still got a bit of the stuff I got from you, Russ. The stuff from Kel is heavier and more consistent. I may have enough of each to give a try at this recipe, but again, it will be some time before I get there.

This summer the priority is trying to get a metric ton of home renovations done.

[Kel Rekuta]

I'm curious as to how the scabbard butts are different, and whether Gavin's stuff is the same stuff I had tanned a couple years back.
(Honestly, my big problem with the bowl shapes, is how do you keep extra material from screwing the shape?)

I presume purposely partial tanned scabbard butts are subjected to a quicker tannage with somewhat stronger tanning liquor. With experience a tanner could estimate rate of tannage and penetration depth. I sincerely doubt it could be done reliably in a home tanning situation. (Without digging a pit in your back yard and uncovering the process periodically.) See Gavin's comments about thickness. I recall the bends I had being 12-13 iron or more. They were tanned in India and might have been water buffalo. I suspect UK scabbard butts are less than 6 iron or 8oz leather. Huge difference.

I am not really sure what you mean by "extra material" Russ. Well sammed hide or rawhide moves like a cooked lasagna noodle. One can press it anyway one wishes given the right form. The half rolled lip around some surviving examples is clearly shaped by the form. I'll photograph the rim striations I noted when I examine the collection again in the next couple months.

[Andeerz]

Where will you be purchasing the scabbard butt leather? And where did you get that half-tanned stuff from India? I am terribly interested in getting my hands on some of that stuff to test some of these processes myself, perhaps help answer some questions, and make meself some kick ass leather armor pieces.

Also, Kei, about that shield you got to handle. You said it was likely made of a single layer of rhino hide... were both sides smooth, or was there sort of a rougher texture to the inside? If it is a single layer, do you know the process used to make this shield or have a good guess?

[Kel Rekuta]

Andeerz,

A couple things... I am in the wholesale import biz, supplying the allied leather trades (shoe, luggage, harness, pet accessory, fetish - whatever) with the tools and supplies they use. I just have weird stuff fall in my lap sometimes. A few bends of imported sole leather came from an historical shoe manufacturer testing an Indian tannery's products. Most were rejects due to the rawhide inclusions. He couldn't even use them for heel build ups because the rawhide snapped edges on cutting tools. (not knives - serious industrial tools) The whole batch of it is gone, except for a few pieces reserved for experiments.

I am currently sourcing scabbard butts. I got a lead this morning but nothing specific. I can tell you that if they become available they will not be cheap. Unless one of our Eastern European friends turns up a supplier no one else knows about, the UK tannery which supposedly produces the product periodically charges a pretty penny for it. Importing small quantities of leather (i.e. a skid of it) from the UK is dauntingly expensive. Starting to see the problem?

Then again, there may be a dozen butts sitting in a dark corner of someone's warehouse, relegated to the unsaleable shelves because the holder doesn't know what they are. It happens.

That's about all I have for you at this point. If it is commercially viable to bring some of these in - I guarantee you I will. The AA will be the first place I advertise whatever I don't hoard for my own nefarious purposes...

Oh yeah, the translucent Persian shield struck me as being a single layer but of rawhide exponentially thicker than any I've seen in 20+ years in the biz. Further research suggests it was rhinoceros hide, which was once available in Iran and other central Asian countries. The face was glossy, presumably from the pressing process, the back buffed. It was definitely lacquered in some way. Closer examination and study will be required as such items are faaaar outside my area of study at this point.

Since you are interested, I suggest you ILL a copy of John Waterer, Leather and the Warrior. http://openlibrary.org/works/OL5544934W ... he_warrior You will learn a great deal about this topic and gain valuable insights into working these materials.

[Andeerz]

Thank you so very much for your response!

Dayummm... I hope your search for commercially viable scabbard butts and the like proves fruitful!

And that shield... when was it made?

Also, how hard and resilient do you think that shield is? Sort of a dumb question, I know... but I am curious as to how it felt in your hands.

Also also, thanks for the book recommendation. I will certainly get my hands on that John Waterer book in the near future.

[Len Parker]

Everyone seems to be thinking that the iron filings act as a sort of hardened barrier within the shield. But I was thinking they might act as miniature dowels penetrating the surfaces of the leather, helping lock them together just like joining wood with dowels and glue. Just a thought.

[Russ Mitchell]

micro-biscuits... the filings wouldn't respond to the glue, but they might help to transfer stresses between pieces...

[Kel Rekuta]

Might that be the purpose of the ground glass or marble then?

[Len Parker]

Exactly Kel. Glass, marble, iron would all serve the same purpose. They would give it structure and strength at small points across the entire piece.

[Kel Rekuta]

Hmm. I'll have to start saving the cutting slurry from the next marble tile job.

I've got a bend of partial tanned veg on order. No idea when it will show up but this is shaping up to do a long awaited commission. This is going to be one expensive round shield.

[Andeerz]

Oooo!

Kei, if you ever do another order for half-tanned leather, would it be possible for me to chip in and get myself some? Also, about how much per square foot is it if you don't mind me asking?

[Kel Rekuta]

Estimate has a four square foot piece at about $100. No surprise why nobody in N.Am. stocks it.
I ordered the largest piece they had uncut since I'm trying to reproduce a Persian shield. Good thing its an institutional client.

[Russ Mitchell]

Ridiculous. I'll just tan some myself this summer and be done with it.

[Andeerz]

Hmmm... not as bad as I expected!

However, I am curious as to if half-tanned leather is simply veg tanned leather that isn't left in the tanning liquor as long. If so, I'd imagine it wouldn't be difficult at all for a North American tannery to just botch a few batches intentionally, have those stored away somewhere and sell them as a specialty item, certainly for less than $25 a square foot! It's not like it would require new equipment or a totally different protocol, would it?

Then again, I'd imagine that making half-tanned leather is probably more nuanced than that. Otherwise, why would it cost so much?

That said, I wouldn't be too averse to chipping in for a shipment sometime in the future if anyone decides to get some! Also, Russ, I would certainly be interested in purchasing some half-tanned from you if you make enough extra to sell. If you do, can I call dibs, unless someone with a super mega awesome project needs it?

[Kilkenny]

If the material is half tanned using vegetable tannins, then I wonder just how much chemical reaction there is between the iron and the tannins. I would expect that the iron filings would not actually hold up to act as biscuits, but would react with the tannins. Interesting.

[Andeerz]

Kilkenny, you might be on to something. Perhaps any Fe(II) ions (not the elemental form that comprises most of the filings) present in the filings (there has to be some small bits of rust there...) might participate in Fenton chemistry or something, producing free radicals which could then chemically modify other things. Maybe the filings react with whatever substrate in which they are embedded (like a glue paste or something... I dunno how the filings are applied! Knowing that would help!), catalyzing the crosslinking of this or that or hardening something. Hmmm... Just throwin' that out there! And only a small amount of the +2 ion is needed, as it is a catalyst!

EDIT: Check this out! http://en.wikipedia.org/wiki/Bioadhesiv ... t_adhesion

So, the iron ions could maybe in theory lead to cross-linking of certain polyphenolic proteins or polyphenols (like tannin!) via free radical polymerization or something! Perhaps this could form polymers that enhance strength somehow... I dunno.... I'll look into it more.

EDIT EDIT: Some more... http://en.wikipedia.org/wiki/Polyphenol#Chemical_uses Hmmm...

[Baron Alcyoneus]

I've used tannic acid to color steel. It gave it a nice dark gray color.

[Kel Rekuta]

Hmmm... not as bad as I expected!

However, I am curious as to if half-tanned leather is simply veg tanned leather that isn't left in the tanning liquor as long. If so, I'd imagine it wouldn't be difficult at all for a North American tannery to just botch a few batches intentionally, have those stored away somewhere and sell them as a specialty item, certainly for less than $25 a square foot! It's not like it would require new equipment or a totally different protocol, would it?

Okay. Couple things that might end the speculation:

Two things affect tannin penetration - concentration and exposure time. Generally speaking, modern vegetable tanning is done in a series of vats containing progressively stronger concentrations of tannin. Time in each, agitation of tanning liquor, et cetera are a science at this point, not an art. There is no "unintentional botching" in modern processing plants. Third world countries - not so much.

Any vegetable tanned leather with untanned inclusions is highly undesirable because it snaps razor edges on cutting tools. Therefore, tanneries that wish to remain afloat in an extremely competitive market must avoid this. If their QA departments do their jobs, leather with inclusions is sent back to the vats. Simple as that. There is a very strong bais in the industry against stock piling product with a very low profit margin. Its all about turnover. Hence, you won't find a tannery with this stuff on the shelf unless someone specifically wants it.

A large percentage of the price of the product under discussion is due to the high cost of bringing small shipments of leather product from the UK to N. Am. From previous experience, this can be 25-50% of the value of goods. Add a very specialized niche market that demands consistency over time, a single producer and exclusive market chain... see where this is going?

If you don't want to pay the price for a very specific product marketed through a tight supply chain, dig a pit in your backyard or get a series of barrels to tan hides. Start collecting and grinding bark, oak galls, sumac, et cetera to steep your tanning liquor. Spend a few weeks experimenting like Russ has done. Then you might get something useful to experiment with.

The soap box is now available for your pontifical or speculative comments...

[Kilkenny]

chuckle. I've been gathering oak galls for months. But I've no desire to try home tanning, especially not in my little suburban development. I'm collecting for ink

[Russ Mitchell]

What Kel said.
Tanning leather can be a bitch. It is absolutely the last home hobby you should get into, unless you're sitting on multiple acres.

[Andeerz]

XD Thanks for the reply, Kei! I've learned so much from this thread!

Yeah... I won't have acres of land (if ever) for another 10 or 20 years yet... so, yeah. If anyone will be looking to get a batch shipped over from overseas, let me know. I might be in the financial position to chip in for some and help save on shipping costs.

If anyone here is willing to make some, that would also be cool... >.>

[Andeerz]

I know this is an ancient thread, but it's one worthy of an occasional digging-up as it has very useful information.

I just wanted to make a further speculation about the recipe that is the subject of the thread:

Though the application of hot hide glue is probably not going to make the entire piece hot enough to harden as per what we hypothesize is going on in "cuir bouilli", I would wager that the drying process itself would if by drying, the author means putting the entire shindig out in the hot summer sun for a few days. However, I do not know if the leather would have been moistened prior to glue application or how thoroughly moistened the leather would have been following glue application. And, from my experience, moisture is required for hardening.

Also, with regard to temperature, you might not need temperatures in excess of 180 to get hardening. You do if you want it to happen in a short time, but perhaps you could get away with lower temperatures if you expose it to a lower temperature for a long time. I dunno... gotta test this crap out myself. But I imagine leaving leather out in the sun makes it get pretty hot!

[Russ Mitchell]

Andeerz, any application of hide glue thin enough to actually penetrate the leather will by definition moisten the piece. Probably not on *both sides,* but the outside definitely.

[Kristoffer]

just a thought, could: "...and nayle hym to the scylde and lete hyme drye..." refer to affixing the leather to a form or last for the drying process?

Sounds reasonable to me. Nail the edge (hymn?) to the shield (mold?) and let hyme (could this be hide?) dry.

Edit: Totally missed that this thread has more then one page of posts. Blaming that I am on my mobile..

[Kilkenny]

Couple of things here. One, application of hide glue could be done from one side such that it penetrated clear through (we don't know the thickness of the leather her, do we?) and isn't the hide glue melted in water, not just molten cartilage ? (kind of hideous to think of it in that way) So the necessary moisture is introduced there...

Temperature where the chemical change that hardens leather happens is 167deg. F (thank you Marc Carlson), so 180 is more than needed, but you do need 167. Sitting in the sun is not likely to get you there.

I think the recipe does instruct you to nail the piece to the shield, and I think it means shield, not mold. He's using it to reinforce a (presumably) wooden shield.

I have no idea what the glass is there for - some medieval recipes absolutely do include junk that has no functional purpose...

[Russ Mitchell]

Much like gesso, Kilkenny, he's talking about *powder.* I'd need to actually try it, but I still believe that what they're trying to do is to get the hard material to soak into the leather itself. As the leather eventually shrinks, you get a composite material. This *would* work if the mix was VERY thin, and the hide was stretched SERIOUSLY tight.

Whether it'd be worth the effort, I've not the foggiest.

[Galleron]

In Middle English, schilde is the tough hide at the throat and neck of a wild boar.

[Mac]

G,

It is still called a "shield" by the modern hog hunter. http://www.youtube.com/watch?v=NZ1Mg0a7Tpw

Mac

[Andeerz]

Wow! This is awesome!

With regard to Russ's post...

I was thinking that the powdered stuff sounded an awful lot like some sort of plaster... not that I know if addition of such would actually strengthen anything. I have a feeling it wouldn't, at least if we are talking about glue, as the gypsum part is a filler and doesn't interact much with the glue. I wonder what that powder is. I don't think it's glass... wasn't old english for glass back in the 15th century glaes or something? Anyway, the use of iron, I think might be something akin to the use of iron filings in some cements like those mentioned here. Perhaps the powder of glaste is some sort of reactant that creates a cement of sorts as someone mentioned before on this thread I think... In any case, perhaps the objective was to make whatever was holding the layers of leather together not only strong and able to reinforce the leather perhaps, but also weather resistant, as I think such cements as those mentioned in the link I posted here might be more water resistant than hide glue alone. I dunno. Just food for thought.

Also, maybe the necessary stretching would be accomplished by simply allowing the leather to shrink on whatever form it is on (well, in this case, it would be stretching, since it would be prevented from shrinking due to being secured on a form). I can definitely say from experience that half-tanned leather shrinks pretty readily after exposure to water and drying, and if on the form, it exerts considerable strain, pulling extremely hard on whatever is pinning it onto it.

I don't think you would want too thin of a glue solution. I would imagine you would probably want to dilute it to the point of being watery, but no more than that, otherwise you would probably get too little glue into the leather to actually make a difference when all is said and done. I think whatever water is in the glue mixture is going to soak into the leather no matter what (so long as there is at least a little more than enough water to completely dissolve the glue so that it isn't a goo), and the rate of diffusion of glue into the moist leather will be greater the greater the concentration of glue molecules in the mixture (to a point). Also, the stretching of the leather would be key, as you implied, as would hot application...

[Russ Mitchell]

Glue can be used much like a tanning agent -- you start at a very thin concentration to guarantee penetration, upping the strength of the glue or tanning liquor as you go. Same thing can be done here: you're really not looking at anything ALL that much different from alum tawing.

[Kilkenny]

Much like gesso, Kilkenny, he's talking about *powder.* I'd need to actually try it, but I still believe that what they're trying to do is to get the hard material to soak into the leather itself. As the leather eventually shrinks, you get a composite material. This *would* work if the mix was VERY thin, and the hide was stretched SERIOUSLY tight.

Whether it'd be worth the effort, I've not the foggiest.

Russ, I understand it's powder. I don't understand the purpose

[Russ Mitchell]

Primitive fiberglass?

[Andeerz]

I'm very much willing to bet it's some sort of "cement" sort of thing, as the iron filings mixed with pulverized soda-lime glass (which, I don't know if it was actually prevalent in Medieval times...) and put with water might actually yield a cement when in the glue! I dunno. I need a chemist to bounce ideas off of... anyone here a chemist?

[Kel Rekuta]

Since this old thread was mentioned in a newer thread on binding a leather buckler, I thought it might be best to lodge this link here. After reading this article a while back, I am convinced the blood/spleen/hide glue/ash/marble dust/ground glass is substantially adhesive bulked up with fine particle fill of various types.

Enjoy. http://cool.conservation-us.org/jaic/ar ... 002_2.html