Full Version: Building a boat-hull Boeotian
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As a result of discussions on Roman Army Talk (and the Greek board) I decided to build a "boat-hull" shield to try some "new" construction techniques. After some consideration, I elected to build a Boeotian vice an aspis, as I believe that the aspis developed from the Boeotian.
I recognize that many people disagree, and I accept that. certainly, I think we can all agree that the evidence is so patchy that it is unlikely we'll ever agree, achieve consensus, or find the "truth."
However, sometimes a good reconstruction can either support an hypothesis or destroy it, or provide data points towards a new hypothesis.

So first, my assumptions. These may not be facts, but they are the core data towards this reconstruction.

1) The Boeotian is descended from the "Diplon" shield and was, at some point, merely a piece of hide stretched over a frame.

2) The frame of the Dyplon/Boeotian was at least in basic form similar to that of the Masai and Zulu shields that I have handled--with an upper and lower rim or edge bound to a central core or spine (I call it the "keel".)

3) That the main facing of this style of shield is not bronze, but rawhide. I believe that I can support this in a number of ways--quotes from the Iliad, for instance. But this is an essential assumption, and if you don't accept that rawhide was, at least possibly, the facing on many shields from 700 BC to at least 450 BC, then nothing about this reconstruction will interest you.

3A Digression--why rawhide? Most importantly, rawhide can be stretched and formed to three dimensional shapes--like the bowl of an aspis and the front face of a Boeotian. It then dries hard--and light. It has been used by many OTHER societies as a shield facing--and some early shields from Olympia have "shield furniture" and even bronze rims, but were clearly NOT fully faced in bronze. Also, see below about Alcibiades's shield.

My theory also had to answer several questions.

A) If shields were hard, thick, and durable, how come there are numerous literary references to men being wounded THROUGH their shields? These seem to exist from Homer to Thucydides.

B) if shields were solid wood, why are there suggestions in literary sources that a shield can be beaten in, or collapse?

C) (Perhaps most important) If shields were heavy--and we usually interpret the aspis as a heavy shield--why is it almost NEVER shown in vase art "on the shoulder", whereas it is often shown extended at the full reach of the arm? is this an artistic convention? Or were the aspis and the late Boeotian relatively light?

And finally, although I chose to look for ways to make my Boeotian light, it had to be capable fo having a man sit on it--as men are often displayed sitting on their shields in 6th C. art. And I think that I should close these assumptions and suppositions by saying that I'm trying to recreate a shield of roughly 550 BC, and that I'm pretty sure that shield design and manufacture changed--very profoundly--after about 450 BC into a heavier and more rigid shield.

I immediately faced some design constraints. i had a period illustration of a shield that seemd to show that the outer rim was lashed or bound or laced--which went well, I thought, with my rawhide idea. I also saw that there were cross braces ont he inside of many Boeotians--often shown as dimensionless lines, as cord or rope. this suggested to me that the inside of a Boeotian was "under tension" which made sense to me as the owner of a Boeotian covered in rawhide would want to keep tension on the outer surface at all time--so that damp would not deform his shield. i use rawhide in the field in my other period--I know how a damp morning can affect it.

Finally, I knew from Aristophanes that shield makers were, at some period, also lyre makers. I had just read an article on how lyres were made in the 6th C. BC and knew that several lyre arms had been discovered intact, and that the arms were steam-bent, as least according to the archaeologists, and when the University of PA did a lyre reconstruction the steam-bent the arms. In addition, lyre construction involved a lot of wooden pegging and glue.
So one of my assumptions (#4 I believe) was that steam bent, glue, and pegging should all be important technologies in shield building.
Close examination of the aspides available to us (the Vatican, the one at Basel, etc.) strongly suggest that the face of the aspis--and this is a fairly fully developed aspis--was composed of strips of wood--willow, in fact--laid side by side and reinforced with a bronze band on the back. Someone (it may have been Paul Bardunias) christened this approach the "boat hull" aspis.
Finally, examination of coins and statuary suggested that the Boeotian had a "keel" or heavy wood mid-rib, based on the shape of the best preserved coins.

I'll try to illustrate my building techniques as well as some of the contemporary vase-paintings that influenced it. I wish to admit up front that I used bronze nails to attack the pine strapping on the face--no fastener would, in fact, be required to hold the strips in place because the rawhide does all the work once it's on--but I had no rawhide when I reached that stage and I needed it to be stable. Aside from that corner that I cut, all the rest of the construction is dowled, mitred, and chiseled, and in as many cases as possible I used techniques that are at least speculated to have existed--but I didn't hesitate to use a power tool to remove wood, where a hand tool would only have done the same in a great deal more time!

Here's my initial design diagram for my steam bender.

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Here's his finished product.

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Now that I had all the steam-bent parts, I had to mitre them all together with a chisel. I put the cross pieces into the rims first. Note--my steam-bender mis-made the rims, so that they are too narrow and not cthick enough. However, if I ordered new ones my cost would have been into the $1000 range before any work was done--and for my experiments, I could survive with flat rims. But please note--everything I'm going to do on this project would have been easier with 2 inch wide rims!
So yes, Giannis--I KNOW they look odd. Smile

Here's the first cross piece mitred into the top rim piece.

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Here's how deep I cut the keel into the cross pieces.

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Those holes you see are where I'll lace the rawhide cover onto the shield--in about 40 hours of work...

Here's the in-cut.

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First cross-bar in place.

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Cross bar and round tensioner (the item that gives the Boeotian its distinctive "cut-outs") in place and pegged.

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Close up!

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Pegging the keel to the cross bars.

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The frame or rim and keel system all together, pegged, glued, and stable.

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At this point, the whole system is under tension, and I SUSPECT that if I were a better woodworker, I could have done the whole thing with friction.

Now I'm putting the "willow strips" on. Mine are pine or spruce, and they are the only stripps I could get--ridges screen door edge at $1 a foot. They worked splendidly, and in summer time, I'd split my own ash, the way we do making baskets. But please ignore the stripe effect or the ridges.

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The underside, showing how well fitted the "boat-hull" is. It doesn't need to be watertight--just tight enough to support the hide, or bronze.

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Cross section, showing how thin the shield face will be--about 8mm.

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Tomorrow, I'll finish the wooden face and sand it to the final shape before laying on the rawhide...
Ahh! So far, it weighs a little under 6 pounds. With rawhide, porpax, and antelabe,. I suspect I'll still get in under 5 kilos, and you can already stand or sit on the face. It is remarkably stable for something so light. Still a long way from finished, however.
Her's the shield with the "decking" complete. Note that I have decked right over the "cut-outs" or tensioners. Just to save time.

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Edge on. Looks shallower than it is--a camera angle, I guess.

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And you can stand on it Smile ) )

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And you can stand on the "planking"

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The inside, all woodwork completed.

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Final form:

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The tensioner with the "cut out"

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Now I decided to add a layer of linen--just to save money, because a layer of rawhide will run me $100.

Sanded and ready!

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Linen on. Looks pretty good.

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But nothing is ever quite as easy as it seems.

I was measuring my 85% complete shield for a porpax and discovered that the porpax goes right in the middle--not on either side of the middle. So I had to add a new support--I steam bent it myself in ten minutes. Of much lighter wood, and Oh, that was a painful lesson. I've over-built this as to weight. Everything could have been much lighter.

However, one thing Aurora and I have constantly asked ourselves is why the original porpakes--especially those from Olympia--have dozens of tiny nail holes that runn all along the "decorative" brass supporting band--instead of a couple of heavy rivets at the base of the porpax where it takes the strain when it is on your arm.

BUT--it suddenly came to me today that if you have a boat-hull construction and the "keel" runs UNDER the porpax, then every pair of holes would provide you with tiny rivets or nails going THROUGH the keel and into the "planks" which would run across the keel--a different design from this one, but one I'm now convinced would work better. Sometimes I can only learn by doing.

Here's the new cross "beam.'

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Next--the the tub even now.
Nice work Christian!

First, THANK YOU MATT AMT! Last night, in the last moments before putting the rawhide on, I went back and re-read Matt's website (and what a great website it is) and accepted his warning that rawhide shrinks and has enormous power when shrinking at face value.

Second, I believe that I was right six months ago when I claimed that the "cut-outs" were there because of the way rawhide behaves when shrinking. In a nutshell, heavy rawhide doesn't shrink at a uniform rate across the hide--the thinner "belly" shrinks at a very different rate from the thicker shoulders. By placing a torsioner int he "cut out" that allows the rawhide to be tightened along a radius instead of trying to get it "out to the side" on an oval, you can have a deeply dished convex surface on your Boeotian and still stretch the rawhide tight.

There's another factor/artifact of the creation process. On Matt's website, you can see one of his shields bent under the strain of rawhide contraction. The WHOLE POINT of the Boeotian shape (as I suspected) is to crate a frame that resists that shrinkage. If that frame had long sides (an oval) one or both of them could easily collapse inward under the pressure of the rawhide--snapping the rim or simply distorting the finished product. I suspect that a perfectly good oval shield could be built by decking over the cut-outs (as I did initially) and leaving the torsioners there as braces--but the belly of the rawhide would then have no place to be "collected" as it shrank, and so there'd be bumps in the surface--OR the oval would have to be flatter and less convex.

My first boat hull is 95% dry and solid as a rock. I am worried that the last 05% of drying may warp the frame, but I don't THINK so. Weight is heavier than I'd like--it is 9 pounds now and hasn't got a porpax or antelabe. But I don't think I could get ANYTHING through the face of it. Not on the first try, anyway!

Now some pics. This is the rawhide over the shield. Luckily, when I was getting ready to tear my hair out, I remembered that I had another set of bent wood "rims" and I used them as "clamps" as I fitted and cut the hide.

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See how the hide already wants to buckle at the "cut outs". Nothing to do with the actual cut out--but cutting the leather here relived most of the strain!

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ready to start cutting holes and lacing.

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This will give an impression of the thickness of the hide--about 3/16s and more than 1/4 at the shoulder. (3mm)

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All laced together, so loose I thought I'd have to cut it apart int he morning and try again.

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Ditto. I know it looks tight, but it was NOT. Note--I also thought that the hide was already dry. It had miles ot go, but the tabs on the outer edge were already too crisp to take shape. It should have gone back in the tub after the lacing holes were done.

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This morning. 95% dry, I think.

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The edge. Next time, I may lay on a rawhide rim.

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The interior--now so tight nothing flexes, and a couple of planks are a little out of true from the pressure, but in general, it's nice.

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Glad my "potato chip" experience has helped! One immediate word of advice: IT IS NOT DRY YET. A day or two is not nearly enough, especially if it's in a basement. A week or so in a dry upstairs room, with some sunning on dry days, and you'll be closer to "dry", but I'm not sure how long it would be until I really trusted it! Even after a few weeks, transitioning from basement to upstairs can do weird things. We faced a Roman scutum with goat rawhide, got it neatly fitted and glued on, and after an hour or so out of the basement, the facing started wrinkling, bubbling, and peeling off! We glued and weighted it down again, stitched it securely around the rim, and it's pretty much behaving now, but it's still not as flat as when it first dried. Weird!

I'll be watching your experiment! Really nothing I can add about your methods, except that I hope they work. I can't help thinking that the shape of the Dipylon shield was the RESULT of using rawhide over some sort of semi-flexible frame or backing, that the backing or framework was designed to "aim" the shrinkage to a workable shape (not concave like mine!). Who knows, maybe the frame started out rectangular (with cross-braces?), and as the rawhide dried it pulled everything into a shape with convex top and bottom and concave sides? The older ones look pretty flat, so you wouldn't need much "decking" to make a dome. I'd probably try a wickerwork "deck" for making a dome shape, like we presume for a figure-8 shield. At some point, someone may do enough of these expensive and time-consuming experiments to find the trick, and I have a feeling it will involve a surprisingly lightweight framework. Or a much heavier frame that is simply a form, not a permanent part of the shield?

Good luck!!

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