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making an aspis
Here's the file as .jpg. I'll try to upload it below


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Paul M. Bardunias
MODERATOR: [url:2dqwu8yc]http://www.romanarmytalk.com/rat/viewtopic.php?t=4100[/url]
A Spartan, being asked a question, answered "No." And when the questioner said, "You lie," the Spartan said, "You see, then, that it is stupid of you to ask questions to which you already know the answer!"
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Thank you.
Cheryl Boeckmann
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I’m returning with a few tips as to how to proceed with the overlapping slats method of constructing an aspis, as a response to some of the comments and questions to my first communique. My work schedule at the observatory constricts my time and thus this report is somewhat delayed. During Saturday I would rather be out on the mountain bike or at archery practice. Good thing the weather is lousy – even the cats don’t want to go out!

A Description of the Stages involved in constructing an apsis

First, a form needs to be made – for this I used the ring method and decided to make it concave. Since I had already made one aspis using the ring method, this went fairly quickly because only one side needs to be finished and I was now familiar with my main shaping tool namely an ARBORTECH ( see pic) carving tool that fits onto a 4” angle grinder. Also, while laying up the rings they don’t have to be complete rings but can be made up of halves, thirds or quarters. Also, clamps aren’t needed at this stage, it is easier and better to just use screws for each layer –when the glue is dry, recover the screws and use for the next layer. For carving guidance keep in mind that your finished product will be a set of concentric circles going from wide spacing at the face; going to closer spacing at the shoulder; to hardly any spacing towards the edge.
Second, wood selection depends on what purpose your finished aspis is to be used for. For an aspis that will be subjected to destructive testing such as the Biskupin Experience, an inexpensive wood such as any of the light firs can be used. For an aspis that is meant to be a keeper, Poplar is about the only choice. In either case, I suggest 4mm slats be cut from boards 5 to 6cm thick. This is thin enough to allow bending with little if any soaking (no steam bending or ammonia soaking is needed).
The tools needed will be: lots of C clamps, some Vice Grips of various lengths (see pic), >100 screws and washers, and a decent hand held jig saw. And don’t forget about a liter of carpenters glue.
The aspis will be constructed of two different parts – the bowl and the rim .
The justification and engineering precepts for choosing the slat-method for building the bowl:
1. Each curved slat tends to dissipate compressive forces fairly evenly, out towards the edge.
2. By criss-crossing 3-4 layers, these compressive forces are further directionally dissipated.
3. The criss-cross fibers with each slat tend to confound the penetrative energy of projectile points.
4. The criss-crossed slats can greatly retard splitting.
5. A tensioning surface of cloth, leather or metal is less called for.
Justification for the rim as a separate element.
1. The rim acts as a compressive band to contain the outward forces transmitted through each slats.
2. The rim can absorb quite a bit of energy applied to its edge without propagating this force to the bowl.
Well, at least this is what theory seems to suggest.
Third, bowl construction via overlapping slats. This is the hardest part of this whole process, which I found to be tedious and often frustrating. The problem is that most of the slats will be subject to a compound curve as they are pressed into place. This means that each slat will have one curved edge where it snugs up against the previous slat and this curve is hard to get perfect. Therefore, I would suggest that for any aspis destined for a Biskupin Experience or other destructive testing method, gaps between slats should not be of great concern. However, for a keeper aspis of poplar, every effort should be made to keep the spacing between slats as tight as possible. For my part, I made tight slat spacing a personal goal. The 1st aspis of southern pine had some spaces as large as 2 to 4 mm and these were caulked with thin strips of wood. The 2nd aspis of poplar was faster due to no need to steam bend and this allowed me to relax a bit and spend more time on shaping each slat, resulting in no gap greater than 1 to 2mm. Once whatever number of layers are chosen (3 or 4), keep them clamped in the form for as long as it takes for the wood dry – even put the whole thing out in the hot summer sun to cook. I didn’t do this and the poplar aspis is less than perfect due to some post form warping. It is more than a cm out of round – hard to see but it offended my sense of craftsmanship.
Fourth, once the bowl portion is complete it will require trimming and fine tune shaping. From the curve of the shoulder to the edge, wood needs to be taken away to reduce the thickness to about 3/5 of the face thickness. The tools I found helpful here are: a radius carving tool (spoon plain) and a carvers rasp (ring file) see pic. Small disc sanding pads (2-3”) known as sanding mandrels can also be useful. Also at this point it is time to measure the depth of the bowl and trim the edge if required.
Fifth, now the rim needs to be assembled and this is also tedious. This is where a round-as-possible bowl is desirable – if not, each section has to have a custom curve to it. Basically, the rim is made of 4 layers, each 5mm thick and each layer is made of 6 – 7 smaller arched pieces. Shaping each small section to fit the edge exactly also requires that each piece be numbered, and it location marked in place on the aspis edge. Once all rim pieces are made, they are layered like bricks so that none of the joints coincide with the joints of any of the other layers. When this assemblage is glued together it is surprisingly strong and when pressed onto the bowl it acts like the steel tire on a spoked wooden wheel. Finally, it is shaped to a slope of somewhat less than 1cm at its outer edge to 2cm where it joins the bowl and it projects out from the bowl no more than 5 cm.
Sixth, the bowl and the rim have to be attached to each other – a process requiring two stages. First, you need to confirm that the rim indeed will fit the bowl snugly by tentatively attaching it, pressing it on to the bowl without glue. Once they fit, take them apart and proceed with the internal furnishings to the bowl and whatever coverings you’d like to have for the bowl (paint, cloth, leather or metal). The top edge of the rim will cover the border between where your covering is and the wood of the bowl. Finally, the rim is pressed into place, with carpenter’s glue, and pinned with either wooden dowels or small bronze or brass nails.
Okay that’s it for my verbal description and I fear it probably has the clarity of smoked glass; therefore, for anyone who undertakes this form of construction, PMs may be the best way to answer any further questions.
Concluding remarks:
I have made 3 aspis (one by the ring method and 2 by the slat method) cores so far and each one I consider as a prototype and as such is not completely finished. There has definitely been a learning curve involved with each one. The fourth, hopefully to start in a few months, will incorporate much of what I think I have learned so far and will have proper bronze furnishings with leather bowl covering and thin bronze for the rim, with external and internal art work. When this all comes together a report will be provided.
Please keep in mind that I consider this construction approach as purely experimental based on the following criteria:
• my interpretation of the scant evidence available
• my evaluation of how to get the most protection - both penetrative and blunt force
• with durability,
• without too much mass,
• with the materials available to the ancient Greeks and finally,
• with a methodology that would be comprehendible to them.

Also, I do not consider my approach as definitive, but rather, as intriguing and as worthy of consideration. Hopefully, destructive experiments conducted by those with the man power to subject crude constructs of this approach against other construct approaches will help to clarify matters. I think this is all any of us can do until conclusive archaeological evidence is published. How about a find from the anaerobic depths of the Black Sea!
Also, I have and will conduct point of contact penetrative tests with a Gravity Impactor I have built with which I can demonstrate and publish (with small error precision) the amount of Kinetic Energy involved with about any projectile point I want. Of course, at this time I cannot demonstrate with mathematical precision blunt force KE and results with complete pieces of armor. This requires experiments such as the Biskupin Experience, which can provide numbers for mass and closing velocities
I hope my small experiments and suggestion have some bearing on our collective understanding with this most fascinating ensemble of armor for the Hoplite panoply.
Thank you,
John Dann
.

The photos can be seen by Picassa link:
https://picasaweb.google.com/RoxanaDann/...directlink
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Thank you very much John! A great article and it certainly inspires me to once try it myself!
How did you fill the holes left after you took the screws away? There have been shield core finds with wooden pegs attached on them, and in fact they were peculiar because the peg was protruding from the flat piece. This would suggest lamination like yours!

Khaire
Giannis
Giannis K. Hoplite
a.k.a.:Giannis Kadoglou
a.k.a.:Thorax
[Image: -side-1.gif]
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Hello Giannis
I am honored that you would like to try this method. Also shield core finds with wooden pegs...,I didn't know about this - very interesting - do you have a reference?
About filling the screw holes - the 1st experiment using southern pine left noticable holes so I used kabab skewers - dipped in glue pushed into the hole, trimed & taped with a hammer - then sanded down. The 2nd experiment with poplar was easer - most of the screw holes closed up leaving a much smaller hole & here I just used wood filler.
John
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The reference for the pegs, and also for the bronze links with rivets that i mentioned elsewhere is: Stamatopoulou V. "Hoplon, the Argolic shield and its technology" http://invenio.lib.auth.gr/record/18179
Khaire
Giannis
Giannis K. Hoplite
a.k.a.:Giannis Kadoglou
a.k.a.:Thorax
[Image: -side-1.gif]
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Any news on getting more than that one page the link leads to on this?
Paul M. Bardunias
MODERATOR: [url:2dqwu8yc]http://www.romanarmytalk.com/rat/viewtopic.php?t=4100[/url]
A Spartan, being asked a question, answered "No." And when the questioner said, "You lie," the Spartan said, "You see, then, that it is stupid of you to ask questions to which you already know the answer!"
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No, i have gained access to the library but i have to go to the unoversity to get it. And can only get it for some hours. Being in the army does not help though. I will tell as soon as i have news, i promise! I only hope that this is not going to be a disappointment!
Giannis K. Hoplite
a.k.a.:Giannis Kadoglou
a.k.a.:Thorax
[Image: -side-1.gif]
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Anything is welcome. I'd like to know more about those grooves.
Paul M. Bardunias
MODERATOR: [url:2dqwu8yc]http://www.romanarmytalk.com/rat/viewtopic.php?t=4100[/url]
A Spartan, being asked a question, answered "No." And when the questioner said, "You lie," the Spartan said, "You see, then, that it is stupid of you to ask questions to which you already know the answer!"
Reply
Hello All, I have seen a shield online with a diameter of about 24 inches weighing about 1 kg. Could that be used for re-enactment ? The shape, though smaller than your regular 32" and larger shields, looks fair to me. I must say that I am about 5.4" in height so a superlarge aspis would not work well for me.

M.VIB.M.
Bushido wa watashi no shuukyou de gozaru.

Katte Kabuto no O wo shimeyo!

H.J.Vrielink.
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Another question :

Where can I get the brass inner parts of an Aspis ? Are they for sale somewhere ? I mean the rings as well as the piece you put your arm in.

[Image: images%5CDS02D_1_l.jpg]

M.VIB.M.
Bushido wa watashi no shuukyou de gozaru.

Katte Kabuto no O wo shimeyo!

H.J.Vrielink.
Reply
Manning Imperial?
Visne partem mei capere? Comminus agamus! * Me semper rogo, Quid faceret Iulius Caesar? * Confidence is a good thing! Overconfidence is too much of a good thing.
[b]Legio XIIII GMV. (Q. Magivs)RMRS Remember Atuatuca! Vengence will be ours!
Titus Flavius Germanus
Batavian Coh I
Byron Angel
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Yes Giannis also said something like that. But since the shield I am getting is not an historical reconstruction but made of composite wood, and the guy making it will not put the straps on it as I requested I probably will make the porpax myself from a sheet of brass I still have laying about. It is not so much for re-enactment as for the departure of my professor of ancient history as well as secondary school classroom use.

M.VIB.M.
Bushido wa watashi no shuukyou de gozaru.

Katte Kabuto no O wo shimeyo!

H.J.Vrielink.
Reply
Quote:... as well as secondary school classroom use.
Ah, so your school children in the Netherlands are as unruly as the Scottish ones! :wink:
posted by Duncan B Campbell
https://ninth-legion.blogspot.com/
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Most definetely !! Wink

M.VIB.M.
Bushido wa watashi no shuukyou de gozaru.

Katte Kabuto no O wo shimeyo!

H.J.Vrielink.
Reply


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