14th C arms in progress

[Leonardus]

Loosely based on these:



The cop .050 4130, everything else is .040. Criticism welcomed.

[ManOnFire68]

Looking nice! Did you do any sketches full scale or otherwise?

[Kristoffer]

Looking good. I would say that looking from the view where you stare right at the point of the elbow, I feel that you have exaggerated the shape at the wrist. I would not have shaped it that agressively there. This is not my century however so dont trust me.

I believe your elbow could do with a more agressive point to it when looking at it in profile.

Also, note how the front end of the vambrace of the original has a distinct angle and a "kink" on the inside at the wrist.

Are these supposed to have turning slots for the vambraces? I recall it being so, allowing for a tighter shape at the wrist. Someone else will probably chip in with more accurate information.

Edit: yes, the slots is there on the original. Yay!

[Leonardus]

ManOnFire68:

Thank you and no, other than drawing the patterns I have not. Would have been a good idea but it is hard to get a tracing of yourself by yourself. As a consequence, this set is going to end up too small for me to wear. I didn't make the meaty part of the vambrace large enough in diameter. I plan to finish these anyway and give them to somebody with slightly less chunky forearms.

Looking good. I would say that looking from the view where you stare right at the point of the elbow, I feel that you have exaggerated the shape at the wrist. I would not have shaped it that agressively there. This is not my century however so dont trust me.

Thank you too. Compared to the originals they are. But I'm fat with fairly large forearm muscles so they follow the shape of my arm pretty well. Except toward the elbow, where they needed to be larger.

I believe your elbow could do with a more agressive point to it when looking at it in profile.

Also, note how the front end of the vambrace of the original has a distinct angle and a "kink" on the inside at the wrist.

I dished these elbows and I was in danger of thinning the metal too much at the center. They were deep enough to articulate so I stopped. I'll raise the next set. The "kink" was there before I trimmed the wrist opening to slope from the fan side to the inner. I'll put it back.

General questions I have. Should the opening at the wrist have a round cross section or more oval? Do the articulation rivets in the cop need to be coaxial from side to side? I've been told no, but I'm not so sure...

Why are some lames I've seen on different arms straight at the cop side while others are "scalloped"?

[wcallen]

Why are some lames I've seen on different arms straight at the cop side while others are "scalloped"?

Generally I think the variation is due to various levels of laziness.
The "perfect" articulation would have very carefully formed "scallops." The arc over the center of the lame allows the underlap to remain exactly consistent and even along the full length of the lame when the lame is moved all the way out. The bumps on the end of the lame allow there to be material where it is needed to allow for a hole for the rivet. Some of the real ones actually have a hard corner between the end of the arc and the extension for the rivet. Modern armourers tend to avoid this to avoid the stress concentration point.

Some people don't bother to be that careful. A single arc on the inside of the lame will tend to have a much smaller amount of overlap between the cop and the lame at the center and more as it approaches the rivet articulation point.

The first design really does tend to work better. There are certain cop shapes that will put up with the extra lame material better than others. In your case, the scallops will help you.

Mac has done drawings showing this... actually we did the same thing a long time ago too. I bet some of them could be found on the AA somewhere.

Wade

[ManOnFire68]

Wade's right, I'm sure there has been more discussions and sketches in the past but here is a link to one of the more recent threads:
viewtopic.php?f=1&t=170292

I found the thread immensely helpful as far as articulation and lame design go.

Zach

[Gaston de Clermont]

You did that vambrace shaping cold? Mad props, man. Heat's your buddy, and will save you some pain there. I'd like to invite you to revisit your lame pattern. Because the cop side lames touch each other when the arm is straight, they may be a little tall. And in the thread ManOnFire68 pointed to above, you'll notice the patterns Mac suggests have a shallow arc to the base of the lame. It allows for a little hyper-extension of the arm.

The sharper cop adds a lot to the look. You'll have to raise it (or do some welding hack) to get that point.

I haven't found a good way to leave the cuff without a roll and wear the arm without a gambeson. Even carefully crafted, there are points were that thin edge will cut you; rarely deep, but you're always bleeding a little. A cheat I like is to fold the hem of the wrist inward before you start to shape the whole thing. It preserves the looks of the original and keeps your blood on the inside.

[ManOnFire68]

I would also like point out (if it's not already known) that most elbow points (on the well made cops) have an apex that is slightly more towards the rear brace side. Don't belive me? Take a good long close careful look. This design actually caters more to the shape of the human elbow. Just FYI.

Zach

[wcallen]

Make the lames work. Move in and out correctly and move the amount you need.

They didn't worry at all about lames crossing in the middle. It happens many times on real armour.

These cross nicely (as one example):
http://www.allenantiques.com/images/A-2 ... -lames.jpg
On this arm:
http://www.allenantiques.com/A-27.html

There are cop geometries where they will tend to cross more than others (narrow cops are a good start).

Wade

[Leonardus]

Zach and Wade, thank you very much. I now have a much greater understanding of what I need to do in the future. I missed Mac's thread somehow. I made my lames "scalloped" just because I had seen that elsewhere. I noticed that it made fitting the lame much easier, but I didn't know why, exactly.

Oh, and Zach. If you have a good picture you could post that illustrates the apex being higher, I'd be grateful.

Thank you also, Gaston. It was all done cold but it was easy since the metal is only .040. Sadly, heat is not available to me at this time. I always wear an arming coat and I think it will protect me well enough, though it is just two layers of linen. My current arm armor provides much more of a cut threat. If that proves untrue, I'll take your suggestion. My blood really likes the environment better on the inside. A friend of mine was concerned about the overlapping lames but I explained that my elbow will be well forward of the pinch point when they get together.

I haven't had much time the past few days, but I did manage to do an upper vambrace today.



Sorry to seem a bit dense and whiny but, this knee pretty much represents most of the armor I have been able to touch and manipulate personally. It needs 5/8" travel up and down the rivets to function. There seems to be very little properly made armor around here. Even at Pennsic, what was for sale was disappointing. I'm sure I didn't make any friends saying that...but what is, is.

[wcallen]

These are images of a very simple cuisse and knee:
http://www.allenantiques.com/A-169.html
They include some images of the knee fully (or almost) bent.
Stare at them for a while. There are a lot of subtle differences between it and what you are playing with. Then not so subtle differences.

This one is different in many ways from the one above, but it also works in a reasonable way:
http://www.allenantiques.com/A-200.html
Even some measurements (something I don't seem to have the patience for).

Wade

[wcallen]

Hmm. Indianapolis, Indiana. I don't know if/when there will be a next good opportunity for me to come up to the KY area and give a presentation, but maybe watch out for it. I did one with Days of Knights last year, and a "private" one the year before. Or, if you just like driving a lot, I am sure that we will find a date for another get together in NC this year.

I find the ability to actually get your hands on real armour and play with it invaluable. It can often make all of the difference.

Wade

[Tom B.]

There seems to be very little properly made armor around here. Even at Pennsic, what was for sale was disappointing. I'm sure I didn't make any friends saying that...but what is, is.

If anything your comment is an understatement of the issue.

I have helped Wade setup the couple of hands on study sessions he has done here in KY.
If we do so again I will make sure to to post here on the archive.

[Mac]

General questions I have. Should the opening at the wrist have a round cross section or more oval?

The wrist can be an oval. If there were no forearm turning joint, the wrist would have to be pretty close to a circle to let your hand pronate and supinate. The turner lets you make the wrist opining be more like the shape of the wrist, because some of the rotation can happen through the whole lower cannon turning.

Do the articulation rivets in the cop need to be coaxial from side to side? I've been told no, but I'm not so sure...

The closer the pivots are to being coaxial, the "nicer" the lames will move. The problem is that that's not really the best place for them to be with respect to the organic joint. In an elbow, the pivots will typically happen at a place where the sides of the cop are just shy of being parallel, so they will not be coaxial. In knees, they are even less so.

Mac

[Leonardus]

This update took longer than I would have liked. Made a good bit of progress lately. Aside from a couple of fit tweaks and putting a roll on the vambrace, they're ready for heat treating. Nobody noticed apparently, but I put the articulation rivets too far into the fan. That made for asymmetrical lames and changed the axis of rotation. Looks wierd but seems to work OK while wearing it.

Since I didn't make the cops deep enough, I had to get a little more movement from the rerebrace and the turning lame.

Looks OK straight...


Big gap extended. I bossed up the hatched area. I haven't done the turning lame yet.


Better.







Starting over with lessons learned. Raising instead of dishing, with heat!

[Ilkka Salokannel]

Thanks for your post.

I am going to be working on a similar arm in the near future. So thanks for the pics, details and inside view of your results. They will help me, when I get to doing mine.

Looking nice.

Are you going to put the indent in the wing?

[Leonardus]

You're welcome. Just be sure to note the lames are an example of how not to do it! I think I'll skip the fan indent on this pair.

[ManOnFire68]

Keep up the good work!

[Leonardus]

Thank you!

I did heat treat, polish and strap these. I was originally pretty sure they wouldn't fit me but as it turned out, they do fit so yay! My heat treat setup is crude, an old kiln lid and some firebrick with a weedburner for heat. Quenched in near boiling water and tempered at 400F for 45 minutes. No warping. Springy without being brittle. 4130 is your friend.




And a new project.