The Armour Archive

I fear that the big jump in my austinitizing temperatures may be more of a mistake than anything else.

In my notebook from '98-'01, I was doing experiments to determine the lowest practicable austinitizing temperature in a effort to minimize distortion and cracking. At that time my quenchants were either warm water or brine, and it was clear that high hardening temperatures were causing more trouble than low ones. I was getting pretty good results with a procedure where I let the metal cool to just above the Curie point before quenching. My benchmark temperature was 1425°f, which is crazy low, but it was working OK provided the piece had had time to fully austinitize.

My notes are sporadic for the time between '01 and the heat treatment of Toby Capwell's armor in '05. During that time I moved home and shop from Ithaca to Paoli, bought a kiln, wrestled with weird pyrometer numbers, changed over to AquaQuench, had thyroid cancer twice, and had a benign tumor removed from my colon.

My next notebook shows that when I heat treated TC's armor, I used a pyrometer reading of 1525°f as my standard, but my notes give no indication of why I did that. It begins to look like I simply lost track of what I had been doing in all the turmoil. I would hate to think that I had been so stupid, but I am having trouble finding a better answer in my notes.

Now, perhaps that paints a stupider picture of me than is fair. In the time between moving shop and building TC's armor, my notes show several examples of successful heat treating at 1525°f, so I did not really risk the entire armor on an untested protocol. It looks like the AquaQuench let me get away with hardening at a higher temperature, and I neglected to look back and see how that compared with what I had done previously. Since it worked, I just kept doing it that way.

This is not a thing to be proud of, and I present it as a cautionary tale. Don't be like me. Take more notes and look back at them sometimes.

Mac

It may not be quite so bad as I thought. Looking through my notebooks for specific examples I find...

--Aug 7 '01, I did a pair of cuisses at 1425°f and 1450°f . This looks like my first use of AquaQuench, and I seem to have done a couple of scrap lames as a test.



--Sometime between Sept 24 and Oct 9 of '01, I did a bevor at 475°f and then a set of three gauntlets at 1500°f (or so) By that time I was suspecting that the pyro was reading wrong.



--On Oct 10 I had borrowed another pyrometer to check my two kilns against.



--On the next page, I heat treat a Churburg 18 with two visors and a wrapper, all at 1475°f (which I suspect to really be 1460°f )
It is an interesting aside that one of the "pickets" on the helmet cracked while I was waiting for the kiln to cool enough to temper. This will be what drives me to get an old oven to "stop temper" in.



--On May 10 '02 I do a pair of legs and spaulders. 1475°f



---Sept 25 '02 sees three barbutes, all hardened at 1460°f -70°f



--There is an undated entry for a pair of sabatons and an hidden gorget The sabatons were both heated to "just under 1500" and I neglected to write down what I did with the gorget.



--The last heat treating entry in that notebook is a pair of English arms from Dec 10 '03. They are heated to "just under 1500"



So, it looks like I was gradually creeping the temperature up for a couple of years. I wish I had made more notes about "why" in addition to "what" I was doing. It must have made sense at the time, but it's difficult to reconstruct in retrospect.

Mac

There are no further notes on heat treating until about a third of the way into the next notebook....

--The first of these is about TC's armor, but it has neither a date nor temperatures (!)



--A couple of pages later we see that it is Apr 13 '05, and the only temperature note has me boldly heating to 1500°f-1550°f. I don't know if the question mark here means that I was unsure of what the gauge said, or if I remembered that the gauge was reading high.



--The last heat treat note about that armor is also undated, but it has a couple of references to hardening at 1525°f.



So.. somewhere in the hiatus between '03 and '05, I seem to have jumped from a hardening temperature in the high 1400s (which was probably really the mid 1400s) to the low 1500s (which was probably really the high 1400s) I don't have a good explanation for the jump, unless it is like I suggested earlier today; I just screwed up.

Mac

It well neigh time to get this show on the road.

The first thing to go into the kiln will be the cuisses.



We can see that they are not going to fit without some disassembly . Even if they did fit, this would be a poor way to do it. Laying on their sides like that is an invitation to warpage.



First things first, though. The straps have to come off and be saved for reference. They will not be reused, but their lengths will tell me how long to make the final ones. Note that the holes that are the correct tension are circled.



When I installed the temporary tabs, I put washers on the outside so that I could grind the rivets with impunity. Note, how the sparks are getting sucked into the dust collector. It's important not to let red hot washers get sucked in. That sets the dust bin to smoldering, which is exciting, but bad.



A sharp rap with a light hammer drives the rivets out.



Here, I was thinking about how to support the knees in the kiln. I thought about making a fixture to support them in a partially flaxed position, but in the the end, I opted to lay them flat on a fixture I already have.





This is how they will sit in the kiln.



Before going any further, I traced the outlines of the main plates so that I have a reference to return them to if they warp.



Likewise for the demigreave and demicuisse.



These assembly marks will help to keep me from trying to put them together wrong months from now. Don't laugh. If you have never made that mistake, it's only a matter of time.



This is what I have settled on for the wires. The wire that goes from end to end will be the "let in" loop, and the one at the end will be the "take out" loop. The let in is long, and it will probably fall over when it is hot, but by that time it will have done its job. The take out is shorter and stiffer so that I can be sure to snatch it with the hook. It's on the top, so that the entire assembly will enter the quench symmetrically. To do otherwise invites warpage. As it is, the wing will brobably do something weird, but with luck it will be easy to fix.



It is important to do "cold runs" to test whether or not the wiring will do the right thing. When the pieces are hot is not time to find that out. Here is what the knees will look like being slung into the kiln. The support fixture will be in there already.



And this is how they will come out.



The cuisses will go in horizontally, and lay on their fronts. I have the let in loop attached to a brace that supports the back flap.



The take out loop is arranged so the that the cuisses will enter the quench vertically. I have used two thicknesses of 16ga wire here. When the wire is at the hardening temperature, it will be a soft as butcher's twine, and I felt like one thickness was going to be too floppy.



I expect to see Zanetto and Grettir tomorrow as they swing by on their way to Wade's Hoopdoodle, so I will probably harden these on Saturday.

Mac

Excellent!

Mac wrote: This is not a thing to be proud of, and I present it as a cautionary tale. Don't be like me. Take more notes and look back at them sometimes.

Mac

If anything, I'm going to be more like you, and start taking more and more records of stuff. I suspect you're seriously underestimating just how thorough your record-keeping is compared to everyone else's slapdash approach.

Suzerain wrote:

Mac wrote: This is not a thing to be proud of, and I present it as a cautionary tale. Don't be like me. Take more notes and look back at them sometimes.

Mac

If anything, I'm going to be more like you, and start taking more and more records of stuff. I suspect you're seriously underestimating just how thorough your record-keeping is compared to everyone else's slapdash approach.

More notes is always better than fewer notes. That gives you the option of ignoring them if you like. Seriously, though, the very act of writing a note helps you remember, even if you never look back on it.

Mac

I got the cuisses and knees hardened this evening. My first impression is that it went well. There is a bit of curling up of the cuisses, I think, but that should not be too hard to fix.

All the parts were hardened at 1450, and quenched in 13% Aqua Quench at around 95 to 100. They were rinsed off in room temperature water and then put in the shop range at (what is said to be) 450 for ten minutes. That will make them stable enough to ignore.



Tomorrow, I will have a careful look at them and start the final tempering and warp remediation program.



Mac

Wooo!

That has to be a relief that the first run went well. Lets hear it for deliberative process!

The scale doesn't look too bad. Must be doing something right.

Today I did the final tempering and the first phase of warp remediation.

My bracing of the cuisses was pretty ineffectual. Somehow, I lost track of what effect the hinges have on the whole thing. As we can see, they curled up a bit.



Having disassembled things a bit, we can see that the main plate is now narrower than the tracing I made yesterday.



This will have to be shoved back during the tempering. I usually cut an aluminum brace and jam it in, but today I had a clever idea. I made the brace in two pieces, so that I could shape each end properly without having to pry it into place to check the fit.



Using a measurement I took from comparing the cuise to its tracing, I mad a mark to indicate where the brace needed to be screwed together.



That turned out to be a bit ambitious for one go, so I drilled another hole with the brace about half way to my mark.



The bottom needed to be wired to keep it from spreading along with the top.



I put the cuisse in the kiln at about 750 for a few minutes and checked my progress. This pic shows the cuisse in between dips into the kiln. I have rebolted the brace to a greater length, and sprung it back into place.



It went back into the kiln for a few minutes, and the results were good. I repeated the procedure on the other cuisse. It was not a badly curled, and I was able to do it in one go.

The knees had curled in a bit as well, but not very much. They are not as strong as the cuisses, because they do not have hems. This lets me use thinner braces.



Both knees got a similar treatment.

Here is what everything looks like now. There are still some things that will need correction, but that will probably happen under the hammer.



Mac

Do you not need to overcompensate in the bracing? I would have guessed that even with bracing during tempering, that the shape may still have some elasticity drawing it back to its post-quench shape.

Great to see the details of this process! I would not have thought of correcting warps like that.

I have not found spring back to be much of an issue. When the parts come back out of the kiln after tempering, the braces practically fall out.

In truth, I don't know as much about this business as I would like to. Indeed, I can't even remember where I got the idea from. The upshot is that if you apply a stress to the steel while it is in the tempering temperature range, it will creep to relieve the stress. I suspect it is one of those time/temperature things, and that the steel will creep faster at higher temperatures.

You can do this by hand, and with a torch. I have done it before, and will probably do it again. You can clamp the work in a vise and twist it the way you need it to go while playing a flame over it. When it gets into the tempering temperature range, you can feel the steel yield. I suspect that remarkable things can be accomplished this way in experienced hands... all without much adverse effect on the hardness.

Mac

Tableau wrote:Great to see the details of this process! I would not have thought of correcting warps like that.

I have been sort of inventing these techniques out of inspired desperation. It is my sincere hope that others will see what I am doing and invent more.

Mac

I am just taking a moment here to write about the sad passing of Will McLean (Galleron). Will died yesterday morning after a mercifully short battle against a very aggressive cancer. I have known "G" since college in '78. He was a friend and a patron for thirty five years. I can barely turn a notebook page without finding sketches for something I built for him.... or now, sadly, things that I will never build for him.

Just last weekend, Will attended a local living history event, wherein he portrayed a grievously wounded squire returning from Agincourt. He was frail and jaundiced, but determined to have one last hurrah as a reenactor. I set up his tent for him in Friday's beautiful autumn sunshine, and then took it down again in Sunday's intermittent drizzle. It was as though the weather had done it's best to give him a good event, but then could not keep from weeping to see it end.

His armor and equipment are still sitting in my shop, where I had room to set up the canopy to dry. The canvas is dry now, and folded up in its box. The silica-gel desiccators are recharged in back in the boxes with the armor. His swords sit on the chest that contains his hats, his ceramic ware, his "beloved dagger", and the other goods that no reenactor can be without. A lancegay with a pennon bearing his arms stands propped in a corner next to his pavilion tree. Everything is ready to go back to G's house, but G is gone....


I imagine that I will come to grips with the idea of a World without Will McLean, but for now, I cry when I think of it.

Mac

I'm so very saddened to hear the news Mac.
And terribly sorry for your loss.

Oh man. I am so sorry to hear this. I have lots of fond memories of Will; particularly from the Pas' at Pennsic I attended.

Here's a couple of pics of the Late Master G in his armor. Unfortunately, none of them show the nice bascinet that Jeff W made for him. I am sure that many people who do not recognize his name will say "Oh! That guy!"



Mac

Yesterday, I returned my attention to to warp remediation. Although the width of the bottom of the cuisse matches the width of the corresponding place on the knee assembly, there is a discrepancy in the shape.



This smooths itself out when all three bolts are in place....



.... but I really want it to be a nice "relaxed" sort of fit. To that end, I figured that playing a propane torch over the problem areas while everything was assembled up would do the trick. Hanging the cuisses from chains let me do that at a convenient level.



Unfortunately, even after repeated attempts, the parts would not just lie down and behave themselves. This sort of repair with the torch usually involves overcorrection to allow for springback, and I think that is the problem here. I need to get more area hot to make this work.

So, I have put the braces back in and bolted everything back together. I plan to put the entire cuisse assemblies into the kiln at about 750°f - 800°f and see if that does not subdue the trouble. The kiln is warming up now, and I have laid some "furniture" on the kiln floor to keep the cuisse from rolling on its side.




Mac

That trick worked well. The parts now fit in a relaxed sort of way. This pic shows the overlap with one of the bolts removed, and the other two loosened up.



Mac

This afternoon I must turn my attention to making the mold for a pewter funerary badge for Will McLean, which must be ready by Saturday.

With luck, I can be back to the armor in a day or so.

Mac

Mac wrote:This afternoon I must turn my attention to making the mold for a pewter funerary badge for Will McLean, which must be ready by Saturday.

With luck, I can be back to the armor in a day or so.

Mac

As much as I enjoy the progress of this harness and seeing/reading about the way you do this, the pewter badge is more important. Take your time and please make the very best badge. Every one attending the funeral will hold it in regard an think about Master G while looking at it.

Mac friend,
You are a great example to be followed.

The armour is coming along very well but we all knew that it would. You are indeed a master!

That is so excellent of you to do that for Will. I am sure he would love that. Really wish I could be there as I am sure many of us do. He was an amazing gentleman. I think you are right that many recognize him well in his harness. It really is iconic.

RPM

Work is proceeding in the Memorial Badge. Mold making is one of those things that proceeds asymptotically to completion. It goes rapidly at first and then gets slower and slower. Yesterday morning, I had the mold cavity roughed out and was pouring four or five test casts and making changes accordingly. That rhythm of allows for fast work, because the mold never gets too hot to handle.

By sometime in the afternoon, I was pouring ten or fifteen casts to see where the next modifications were needed, and mold became pretty warm.

Last evening, I had come to the point where I needed to make thirty to fifty pours in order to find the three castings that told me what had to happen next. This meant that I needed to set the mold down for a half an hour to cool after each iteration.

I have just made the changes that were indicated by the last casts of the night, and I have the mold "in the cooker" to warm up and dry out before pouring it again. If all goes well, I should have it working satisfactorily this evening. It's one of the little known facts of the craft, that by the time you are ready to cast the fifty pieces that will be the first "run" of a new object, you have already cast the mold between three hundred and a thousand times.

Mac

Very interesting stuff. How did you learn about stone mould making? Off the top of your head, do you know if bronze can be done in the same material, or do people use a different type of stone?

I would love to see this process. You have some amazing knowledge there Mac! I suspect if I tried it that was I would have learned the hard way and damaged the mold. I'd love to see the complete badge once you have a few minutes if that is possible as I will not be able to see them in person.

Thanks for sharing your knowledge of this. I hope sometime to try this out. I did some cast AL work and some sandstone with pewter. I'd love to get into it again.

RPM

Master G's arms are "azure three hourglasses or", and after discussing several options, and making a few sketches, we settled on a badge that was a single hourglass.

Here is the notebook sketch of how it will sit in the mold.



and here is the mold blank, with the hourglass sketched out on the face.



Some way into the process, I decided it would be cool to try to represent the sand and the glass differently, and have openwork within the glass. That complicated the thing quite a bit. It meant bringing all the metal down through the columns, as well as getting several streams of metal to come back together in an orderly way at the lower end. This last thing turned out to be a lot of trouble. There was a tendency to capture air in the lower glass, right in the middle. If I had had all my wits about me, I would have seen that coming, and left the center bottom thin, and force the streams to coalesce and force the air out bottom. Unfortunately, I thickened the bottom in the back of the mold early on, and left no way out except between the halves of the mold back. That turned out to be pretty fussy, and took the better part of yesterday.

Here is what the finished badge looks like.



In order to allow folks to pin it to modern fabrics without damage, we will be supplying the badges on a ribbon with a straight pin. Anyone who wants to pin theirs on in a more authentic way can easily do so.



This is a fussy mold. I was too impetuous at the start and ended up with a thing that must be cast at a higher temperature and with a higher failure rate than I would prefer. It also requires a lose grip or else the retaining clip fails to cast. This makes the pin a bit flashy and complicates the clean up. If this were a regular item in our line, I would spend another day "tuning" the mold, but we don't need than many of them, and we need them now. I cast up about 150 of them last night, and have about 2/3 or them cleaned up this morning. The rest will take another forty five minutes or so after breakfast.

Mac

This is very beautiful.

Mac,

Right I remember seeing his arms on his pennoncel blog.

Those are awesome! You did a great job in making those! I think they are indeed a great tribute to Will. It will be neat to think of all those people there wearing his badge.

Wish I could help you out with clean up. Sounds like something a person like me could help out with.

RPM

Beautiful work Mac. And a worthy tribute to a friend.
And the hourglass image is quite meaningful. Aside from being Master G's arms, the hourglass reminds us all to stop, ponder, and appreciate while we can.

That won't be lost on anybody, I'm sure...

Ya know, I always thought the hourglass was a sort of creepy thing to have as a devise. If you wrote it onto a story, it would be "foreshadowing".

Marianne made up a bunch of ribbons last night, so it was pretty easy to get the first fifty done and delivered to chez McLean before noon.



We'll get the remaining hundred pinned up this evening.

It's a pity we didn't think of this a couple of weeks ago... I think G would have enjoyed collaborating on the design.

Mac

Tableau wrote: Off the top of your head, do you know if bronze can be done in the same material, or do people use a different type of stone?

I suspect that the "wonderstone" would hold up to the temperature of molten bronze, but it would have to be preheated well above the melting temperature of the locating pins. You would need some other method of assuring alignment of the parts.

In any case, I don't think the method would be well suited for small stuff with detail. I suppose that the surface tension of the metal and the impermeability of the stone to air would be trouble. You would want to limit your self to stuff that was at least as heavy as an arrow head.

Mac

Those are beautiful.