Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Turned Aspis Project in Progress
#16
More. FYI, the chuck was glued and screwed to the blank. This was the biggest piece Ed had ever turned. We rebalanced twice at the beginning because the wobble was dangerous. We finally figured out that two of the planks near the center were denser than the rest of the boards. That threw off the spin slightly. The piece always came to rest in the same position.
Cheryl Boeckmann
Reply
#17
Another pic. This is where we pulled the piece to turn it around. The exterior was sanded to 200 grit. (Ed normally works to 800 grit. This is where I broke the news to him. The wood would be covered in leather and perhaps faced with bronze sheet. And I would be making holes in it for the fittings. I thought he might weep. I couldn't blame him. It is a piece of art.)
Cheryl Boeckmann
Reply
#18
More. We spent a lot of time rebalancing the shield. Ed's goal was to remove as much material from the "mushroom stem" as possible, then saw the stem away. He worked until he could no longer control the gouge tool. Rather than force it and damage the piece, he stopped a little sooner than he would have liked.
Cheryl Boeckmann
Reply
#19
Last pic at this time. Once we cut away the "post", Ed chiseled and sanded away the interior. He stopped with a 15 inch (381mm) diameter flat circle in the center of the interior. The rest is hand sanding it away to achieve the interior pattern. That's when I took it home. I have removed about 1/4" (6mm) of material. The shield is still about an inch thick at the center. I plan on removing about another 1/4". (Better safe than sorry.) The aspis weighed 15 pounds (6.82kg) when I took it home. It'll lose another 3/4 pound (0.34kg) when I quit sanding. I'm using an orbital hand sander with 60 grit discs. I'll finish with as soft 200 grit pad to bring back the beauty Ed left me with. Pray for sun - I have to do this outside...
Cheryl Boeckmann
Reply
#20
WOW. I mean, really, "WOW!!" Seriously bowing to your determination on this one, Cheryl, very impressed and envious. Just having access to folks with know-how and equipment like that is amazing. But geez, don't mess up!

David, I wonder if it wouldn't be easier to make a lathe for one of these horizontal, like a big potter's wheel? That may be how the originals were done. Big disc of stone (or concrete!), mounted on a spindle, perhaps with a flat wheel at floor level so you can kick-spin it by foot. Or motorize it! It would hold a lot of momentum, and the wood block wouldn't need to be perfectly balanced because it would be light by comparison.

I also wonder if some clever work with cross-sectional drawings would allow you to rough-cut the slabs into arcs before gluing them together? Kind of like the plywood-ring method, but on a different plane. Less wood would be required, and it would be less work to shape it.

Go go go, Cheryl!!

Matthew
Matthew Amt (Quintus)
Legio XX, USA
<a class="postlink" href="http://www.larp.com/legioxx/">http://www.larp.com/legioxx/
Reply
#21
I'm lucky I found Edric. I'm especially lucky he was willing to try it. He usually works with much smaller pieces. I was surprised he was going to turn vertically. I was thinking "potters' wheel" myself. I will try to find my pattern and post it as a .pdf. If any one want to lay out shaped boards to save weight and time - go for it. Ed said he would be willing to do another one with conditions. He definitely would want to control the blank assembly. He knew he could get really injured if the blank wasn't perfect. He also cut me a break on price. So, another aspis would cost some bucks...
Cheryl Boeckmann
Reply
#22
This is magnificent Chery!Indeed a piece of art. You said you may cover it in bronze sheet? How are you going to do that?
The ancient shield may have been rather thin in places,so you must keep that in mind,together with the piece staying light but solid.
Khaire
Giannis
Giannis K. Hoplite
a.k.a.:Giannis Kadoglou
a.k.a.:Thorax
[Image: -side-1.gif]
Reply
#23
My dream is to have two interchangeable bronze sheet facings. One plain or with a painted design on it, and one with the Amazonomachy worked on it in relief. (I have some work to do.) I have found a metalspinning company that may work with me on spinning a face. Bronze is incredibly expensive right now, so I have to see what I can do. I can always face it in leather and paint it. I will face the rim in bronze no matter what (it dings easily). I can't use the shield as a spinning blank because it will break. The spinners use hard maple wood blanks on a tool steel base (I toured their plant).

If I can't get it spun, I thought about making a form in my backyard, pressing my shield (protected) into wet concrete, and dishing bronze sheet into the depression. I don't know about that, yet.

Attached is an Arch E size pdf of my shield drawing. It is full size with a cross section.
Cheryl Boeckmann
Reply
#24
Did you make the shield thicker near the rim? I ask because it doesn't appear in the pdf.
The Spanish group Athena Promachos have many decent bronze covered shield.
Khaire
Giannis
Giannis K. Hoplite
a.k.a.:Giannis Kadoglou
a.k.a.:Thorax
[Image: -side-1.gif]
Reply
#25
No. It is not thicker near the rim. There is a little more strength through the diagonal change from the rim to the dish, but not much. I modified Matthew Amt's old "ring" method sketch. I hope not to have to fight much with the thing! In my impression of Athena, I intend to rely on Zeus' aegis :wink: .
Cheryl Boeckmann
Reply
#26
Quote:My dream is to have two interchangeable bronze sheet facings.

Hah, that's no fun! Definitely make 2 whole shields!

Quote:I have found a metalspinning company that may work with me on spinning a face.

Cool beans! Gonna be a heck of a tooling cost, though...

Quote:Bronze is incredibly expensive right now, so I have to see what I can do.

You won't an actual historical alloy of copper and tin. The closest is phosphor bronze, 95 percent copper and 5 percent tin (plus a dash of phosphorous), but it apparently is not made in pieces more than 12 inches wide. Silicon bronze is easy to get (if not "cheap") but has no tin at all. "Commercial bronze" is really a low-zinc brass, 90 percent copper and 10 percent zinc, but probably looks fine. (The scrap I've been using for all my stuff is likely commercial bronze, but I don't really know! Nice stuff to work with, looks great.)

Quote:If I can't get it spun, I thought about making a form in my backyard, pressing my shield (protected) into wet concrete, and dishing bronze sheet into the depression.

That probably won't work. It'll make a terrible mess of the surface of the metal, in any case. Better just to throw a heavy canvas tarp onto the lawn and dish the metal right into the ground! Basically a variation on the sandbag technique. Shape a rubber mallet to sligtly round the face and remove the edges, and dish with that. Once it gets to a bowl-like shape, check the fit on your wood blank, maybe dusting the wood with chalk to make marks on the spots that need more dishing. I'd probably do the bowl and rim from separate pieces, for the first try. Gonna be a heck of a chore annealing the metal, too, but do it frequently.

You can practice on scrap steel, like old shelves pulled out of trash piles. Learn a lot about techniqe without wasting good bronze!

Khaire,

Matthew
Matthew Amt (Quintus)
Legio XX, USA
<a class="postlink" href="http://www.larp.com/legioxx/">http://www.larp.com/legioxx/
Reply
#27
I spent last evening finishing the dishing on the interior of the blank.


Attached Files Thumbnail(s)
           
Cheryl Boeckmann
Reply
#28
Hmm. Back to downloading files. Anyway, I spent about seven hours total shaping the interior.
Cheryl Boeckmann
Reply
#29
So, here's the final blank. Now, it's back to work. I hope to hook up with the metal spinners soon. I am going to gather the supplies needed to fit the interior. I'll post more pics when I get past the next few steps of assembly.


Attached Files Thumbnail(s)
   
Cheryl Boeckmann
Reply
#30
Aren't you just a tiny bit tempted to just oil the wood and show off that great wood grain?

What do you reckon the weight to be of your blank? Poplar isn't dreadfully heavy, as woods go.
M. Demetrius Abicio
(David Wills)

Saepe veritas est dura.
Reply


Forum Jump: