Björns Junkjard

[Indianer]

Hello guys. I don´t know if or what might follow here, but in case it adds up let me open this thread.


I´ve hit a roadblock that I´d like your opinion on.

I tried to draw out a round bar oover the round edge of one of my RR anvils. The bar is too mighty for me, even with me as striker. So I am building a tool. I got myself a proper "warm-working-steel". Resilient and tough in warm condition, adamantly holding its shape to ~400°C/752F.

The steel was a round bar (d= 1,2'', l = 3,2''). I cut it lengthwise in half, now having |) and (|. They will form a clamp to strike upon, squeezing the workpiece between them. Now I need to harden the pieces.

The tempering requires holding them at 450, 490, 470°C| 842, 914, 878 for 45 minutes each because of their thickness. I have my forge and I have a thermometer for it... but I am unsure about how to hold the temp. I doupt I can reduce the gas pressure enough to get there. It is most important that the steel reaches 914, maybe 930 F. But under no circumstances must it get any warmer.

How would you approach this...?

All the best,
Björn

EDIT:

forge 1.JPG (36.19 KiB) Viewed 28653 times

The attachment halves 2.JPG is no longer available

[raito]

What's the diameter of the bar you're drawing?

[Sean Powell]

If it were production critical I'd outsource it to someone in the industry.

For home use I'd probably throw it in my oven on a self-cleaning cycle which is theoretically 471C/880F and call it good enough. I've come to discover that us engineers like very specific parameters to get the peak 99 to 100% of the performance but for hobiests getting 80% is pretty damn good. You will spend more time chasing down a perfect solution than it would take to re-build the tool in X years because of wear and deformation.

Sean

[Indianer]

Sean, thanks for the comment. Unfortunately, there is no such oven in my posession, or anywhere near...

raito, the diameter is 3,2''. It works...but much too slow. I can not crush any grains at this speed. It´s the same bar I make the tool from.

Behold the horror...

ouch.JPG (55.51 KiB) Viewed 28651 times

need to bang it straight the next time I get to it. My assistant was about to collapse the last time from bad "form of the day", so it stayed that crooked.

EDIT: And this is the steel:
Material Data Sheet

[losthelm]

At those temps you can try sending it out to a business that does heat treating or talk with someone that has a small kiln for glass or jewelry work.
lamp work beads and other glass work use the kiln for annealing and shaping glass with precision control on heating and controlled cooling rates.

[Indianer]

Hey guys, I tinkered with the thinning-solution today. Wanted to ask for your opinion on the construction plan.

It is:

construction plan 1.jpg (38.3 KiB) Viewed 28299 times

- U-tube to fit the railroad anvil, bearing a half-round bar and two aluminum pillars

- another half-round bar with a slot (planned location marked with black sharpie line)

- a ~2mm (12 ga) thick metal strip inserted into the slot and welded onto the bar (indicated by wrench)
- that strip suspended on a round rod
- the rod would then have a long slot drilled and filed into the aluminum pillars to slide up and down, as needed for stock thickness

That sound any reasonable? Thank you guys.

Best, Indi

[Sean Powell]

So the purpose is like this:
https://cdn.shopify.com/s/files/1/0225/ ... 1427577981

or maybe like this:
https://www.ebay.com/i/123753733176?chn=ps

The purpose of your proposed pin and slot is to keep the upper piece from moving axially but still move vertically and sit horizontal regardless of material thickness? But the 2mm thick strip is to keep is from shifting sideways or twisting? I think that the first time you hit the top flat and aren't perfectly centered you are going to twist the 2mm thick strip. If your work piece is not flat it will also slide sideways under impact. I would make your 2mm bar much thicker. Maybe even 20mm square!

I'm not certain 2 pillars is a good choice. If both have slots they need to be in-line. If you hit one with a hammer it will twist relative to the other and the pin will not move. Consider a single pillar with slot and then a longer bolt welded to the 2mm/20mm arm. Now you can add a washer, spring washer and nut on the other side of the pillar. You can adjust the spring so your arm moves but is not floppy.

I would not use aluminum for the pillar but it is easy to make the slot. Maybe you can find steel that already has a slot?

I would consider full round for the top cylinder. It will be easier to strike true.

Good luck!
Sean

[Indianer]

Hello Sean, thank you very much for your answer!

So the purpose is like this:
https://cdn.shopify.com/s/files/1/0225/ ... 1427577981

Yes, just suspendable on the anvil.

The purpose of your proposed pin and slot is to keep the upper piece from moving axially but still move vertically and sit horizontal regardless of material thickness? But the 2mm thick strip is to keep is from shifting sideways or twisting?

Exactly! I realize that I should have built my question differently. I tried not to overload it, but a few more technicalities would not have harmed.

Consider a single pillar with slot and then a longer bolt welded to the 2mm/20mm arm. Now you can add a washer, spring washer and nut on the other side of the pillar. [...] I would not use aluminum for the pillar but it is easy to make the slot. Maybe you can find steel that already has a slot?

Brilliant! I will do it that way.

Now you can add a washer, spring washer and nut on the other side of the pillar. You can adjust the spring so your arm moves but is not floppy.

Do you mean a washer like A: or like B?

Best, Indi

[Sean Powell]

Do you mean a washer like A or like B?

Best, Indi

C, Basic flat washer: https://images.homedepot-static.com/pro ... 4_1000.jpg

You COULD replace the spring with your washer B (Also called a Bellville Washer or a disk spring washer in American)

or with a curved spring washer https://www.globalspec.com/ImageReposit ... 6c8b10.png

Or with a a wave washer:
https://s.sears.com/is/image/Sears/PD_0 ... J250002-Z4

A picture is better than a description. This is what I would build to do what you are describing:

[Indianer]

Hey guys, another question before I can proceed here:

I thought I´d best weld the rod to the round bar. I intend to have the round bar hardened. Should I weld before hardening? The round bar is this warm-working steel. I´m concerned about the weld breaking from stress during hardening. If I made the rod from the same steel nothing should happen, right? Then again, weldability is supposed to be bad.

So, will I try to weld it to a rod of the same steel, or go for an entirely different solution?

Thanks again! Indi

EDIT for the links, I checked them and they are still valid in Firefox:
http://www.dorrenberg.es/download/acero ... 44_deu.pdf
https://www.stahlportal.com/en/stock/12344-x40crmov5-1/

[Galileo]

Preheat the metal before welding, then reheat to anneal or normalize the whole thing. That might help with heat-treating with a weld. That said, heat treating after a weld will show where your welding was lacking. Any air pockets will probably cause it to fracture.

If you heat treat before welding, you might mess up the hardening during welding. I have no experience in that regard. I've only welded on mild steel, and that was a couple of decades ago.

Mac should be able to weigh in - I believe he's heat-treated armour after welding on it.

[Sean Powell]

Hey guys, another question before I can proceed here:

I thought I´d best weld the rod to the round bar. I intend to have the round bar hardened. Should I weld before hardening? The round bar is this warm-working steel. I´m concerned about the weld breaking from stress during hardening. If I made the rod from the same steel nothing should happen, right? Then again, weldability is supposed to be bad.

So, will I try to weld it to a rod of the same steel, or go for an entirely different solution?

Thanks again! Indi

I'm sorry but the link doesn't open for me.

Weld cracking is a valid concern if the 2 steels have wildly different coefficients of thermal expansion AND if the weld material is brittle and has stress concentrations to start at. In this case you should be using a low carbon weld filler material that is ductile. The diameter is small and it's a circle to avoid corners.

I would suggest chamfering the rod for 1/4 of its diameter all around, pre-heating the round bar some and then making the weld in several layers by penetrating deep and layering it up. In this case more is better.

Good luck!
Sean

[Indianer]

Hey guys,

the above project is paused atm. I built an interim solution to draw out a knife that is in the making...all stuff for another day.

Today, I have a request: A few words on vambraces. Any ideas/ facts are welcome. I could use a few lines on the anatomical design. They are to become a preamble to a chapter I´m working on. I so far disregarded the following: Someone said, the shape was different over time and region. I don´t know how much, and in what aspects (major curves or just their subtlety?).

So far I am stuck with the following observations, mostly based on Wades collection pics; reference might be this one, or this, this, and this. Never wore a vambrace myself.

1. There are two halves to a closed design, the inner part being called 'door' or 'wrapper' (?).
2. For an arm in resting position (no torsion) the borders are usually directed to the palm and the back of the hand. The hinges/ leathers are usually on WHICH side?? Not enough references to determine that.

3. In both the ulnar-radial plane (plate bodies) and the plane from palm to back of the hand perpendicular to that, the plates bulge out on both ends and have a concave impression around the tendon section behind the wrist.
4. The concave dent is less pronounced at the plate intersection at the hinge (ALSO true for articulating leather strips?).

5. For solid arms (non-floating couters): When the arm is rotated, a vambrace doesn´t follow much, esp. of not articulated via sliding rivets to the elbow lames. Thus... 6.
6. The minimal radius of the concave dent equals the local ulnar-radial plane diameter plus clothing and room for the skin to breathe.

Thx and Best,
Indi

[Scott Martin]

Hi Indianer

I think that pictures would be useful, since I am likely not the only one scratching my head.

In general, the part of the vambrace that is not articulated to the counter I have always referred to as a wrapper (mac calls this a door).

Also in general, the hinge will be facing away from the body, on the same side as the wing or fan.

14th century arm harnesses generally have longer vambraces (closer to the wrist) than later period arm harnesses - in general gauntlet cuffs get longer and the vambrace gets shorter. This breaks down for things like bridle gauntlets, where the “gauntlet” covers the elbow. You will also find more “shape” to early (14th century) vambraces - later vambraces approach a cylinder or cone, rather than a “tulip” shape. If you look at “arms and armour of the medieval knight” there is a nice breakdown of an armour, including the arm harness toward the end of the book. This is probably a useful reference.

Arguably the best reference would be Claude Blair’s “European Armour” (1066-1700)

Others with broader armour chops can weigh in, hopefully this helps.

Scott

(Edit - dang autocorrect can’t hanfle leaving the word “vambrace” alone)

[Indianer]

Hello Scott. Thanks very much for these elaborations, helpful indeed.

Pictures: I feared as much. Let me try to conjure sth. up today... need to find a concept that reflects the written musings.
So long, Indi

[Indianer]

So, here it is. Basically what I cannot for the life of me determine is, blue or red?

vambrace.JPG (47.63 KiB) Viewed 27782 times

I believe I have seen both. Kinda hard to say when you never actually held one in your hand. Nor could I tell which option is better. I agreed for myself to opt for the blue option, with the plate margins along the axis palm-BotH.

Will this help illuminating the subject?

[Johann ColdIron]

The answer of seam line varies on type/timeperiod/location of vambrace as does side of hinge.

I build a later vambrace out of Wades collection in my Cuirass thread. Starting about half way down the second page.

viewtopic.php?f=1&t=186157&start=35

The seam on this set combined with the opening for the elbow made it sit slightly out board from your red dotted line.

The most important things I learned from the prototype I made in the thread, and need to update since I made the pair in 1050 are
:

The door should be thinner metal than the main plate. Wades is.
The door should be large enough portion of the total pattern to be springy so you do not have to fight the plate stud closure into the stud hole.
Door gets less springy once you add hems to the ends.
Door should swing directly into its location under the stud and not have to be pried under the main plate.

Looking down the inside of the vambrace both ends should be round not oval.
Shape should be snug but not Popeye proportions. Unless mail enters from the top at the elbow, then it may have more volume than you actual arm needs there.

[Scott Martin]

I looked through a fair pile of arm harnesses, and it appears that the hinge is generally outside on armour through the 15th century. Most 16th-17th century armour (where the vambrace is generally retained by a stud) the hinge moves to the inside.

From my "snap" answer you can probably guess at the era of armour I favour

Thanks John!

BTW, what proportion of the circumference is the "door" typically - I have been making this cover about 50%, while the main plate of the vambrace covers 55% or so (which means that it has the "overlap" for the hinge side as well as the "open" or "pin" side). This gives enough material to blend a tight seam, without getting crazy on the overlap, which is generally around 1/4".

As demonstrated, just because that's been what I have been doing doesn't mean that is what should be done!

[Indianer]

Guys, I wanted to wait for more possible input so as not to spam into my own thread. Over this I neglected to say "Thank you!" for your comments on this. So: Thank you!
So long, Indi

[Otto von Teich]

I just noticed this. I would use the blue for hard riveted couters with lames, thats about the only way it can be done and function properly. For floating couters on leathers I'd use the red, at least for 16th cent arm harness.

[Indianer]

Hi Otto, thank you for this!

I just dug around my own pics to find references for styles (milanese, gothic). I stumbled over some A62 (Sigismund) pic, seems like the right vambrace has been put on the wrong way around? Fan-side plate is inside on the right arm...seems off, is it?

A62 3.JPG

(86.69 KiB) Not downloaded yet

Another look:

A62.JPG (70.72 KiB) Viewed 26708 times

Left Arm:

A62 2.JPG (35.57 KiB) Viewed 27671 times

[Otto von Teich]

Yes, I think its off. I dont think thats the right configuration!

[Indianer]

The most important things I learned from the prototype I made [...] are:

- ....
- Door should swing directly into its location under the stud and not have to be pried under the main plate.

I would like to put this up to discussion, out of curiosity. Why is that so? Greaves should be made so the rear has to be pried under the front, should they not? Also, I heard someone else state the same principle applied to vambraces. Is it because of some technical reason important during the making, or does it refer to the real thing you were leaning on?

it appears that the hinge is generally outside on armour through the 15th century. Most 16th-17th century armour (where the vambrace is generally retained by a stud) the hinge moves to the inside.

I am so sorry to inquire, but I need cleaning up here: When you say it shifts from outside to inside, do you mean it shifts from blue to red, or from red to red...just opposite sides..?

Thx guys. Indi

[Scott Martin]

Blue to blue, but opposite sides. 15th century and earlier the hinge is on the “wing” side of the arm harness, 16th century and later the closure (stud) is on the wing side.

Note that from the 15th century most are harnesses have the counter articulated onto the arm harness. This requires a solid vambrace between the articulation rivets, so a hinge on the “red” line is not an option.

[Indianer]

Thank you, kinda obvious...much obliged for answering anyway

[Scott Martin]

Many things are obvious once you know the answer. My apologies for not being more clear in my response.

[Johann ColdIron]

The most important things I learned from the prototype I made [...] are:

- ....
- Door should swing directly into its location under the stud and not have to be pried under the main plate.

I would like to put this up to discussion, out of curiosity. Why is that so? Greaves should be made so the rear has to be pried under the front, should they not? Also, I heard someone else state the same principle applied to vambraces. Is it because of some technical reason important during the making, or does it refer to the real thing you were leaning on?


Thx guys. Indi

The only real answer I have for this is that the originals that I have handled in Wades collection do what I described. Also with greaves you have both hands to work together to pry them into place. With vambraces, if you are doing them yourself, you have but one hand to do it. I found this a pain in the butt with the prototype. With the final product self locating the two halves together I can close them and set the pin with two fingers.

But you do want enough springiness to keep them from popping open when struck. Some of that can be the length of the pin you install. Also hemming both ends of the door plate adds to that resistance.

[Scott Martin]

To expand a bit on John's answer, I have found it easiest to built both parts of the vambrace (with the hinge) and match them closely, then pinch the holes for the pin so that the hole goes through both pieces and lines up when you close it. I then make a stepped pin for the "door" and ream out the hole in the vambrace. I tend to use 1/4" / 6.5mm barstock for the pin, so the hole needs to be reamed out to slightly over 1/4". If you use a 1/16" hole for your alignment holes, this works well for a "centgerpunch" for a roper whitney punch - 5/32" for the "door" and 1/4" for the main plate, and then use a 1/4" drill buut to ream it out the extra few thousandths of an inch so that it clears nicely.

This is similar to my article on pin closures here, which I should update having learned a few things in the last 15 years or so...
http://borealissteel.ca/spring-pin-construction/
You can ignore most of it, but the methodology for using a drill press to make the stud is appropriate here. Be aware that this is NOT a period closure method, all the pins I have seen look like they were just smashed into place, and for a helm there will be 2 pins, and a single rivet securing the pin assembly to the helm. I don't have as much practice as the medieval folks, and use different tools, so for me spending 30 minutes to make a pin that I can't screw up is worth the risk of blowing a vambrace that I took several hours (including hinges and hems) to build.

Hope that this helps

Scott

[Jason Grimes]

I have a very easy method to make and set pins, might even be the historical method. Punch the hole for the pin 1/32" smaller than the diameter of the rod you want to make the pin from. On one end of the rod I reduce the diameter by drawing it out a bit on the anvil. I try to be careful here and make the reduced end as even and straight as I can, although it probably doesn't matter much. I also file the reduced end down to get rid of the small divot that is created if you reduce the rod cold. You can skip that step if you reduce hot. I test-fit the rod to make sure I have enough metal to peen it over on the inside. Once the fit looks good I measure out how tall I want the pin to be and mark it. I hacksaw off the pin from the rod where I marked it, trying to keep the end as straight and level as I can. Clean up the cut end of the pin to remove burrs with a file and get the end as level as you can. Then it's just a matter of putting the pin in the hole and peening it over on the inside while resting the other end on the anvil (try to keep it as level as you can, otherwise you can bend the pin, etc). After this you can use a hacksaw or file to put a notch on the side, to help keep it from slipping out when the armour gets struck, if you want.

Should only take about 5 to 10 minutes to do. If you mess it up, just chisel or grind off the peened part of the pin from the inside and punch it out.

[Indianer]

Hey guys,

for a new drawing I want to make I wanted to start out with tracing the sallet form the pic below. Its from the Met: 29.156.45.

From what I see I think it's been taken as should: From a distance with a wide lens, then zoomed in (that right, yes?). Which would mean it's a good one to trust as proportions go, and I could readily trace it. If anyone sees a distortion I should mind and correct, please let me know. Thank you! And have a great weekend.

Indi

[Scott Martin]

I think that this is one of the ones that was made for Maximillian, and most folks (who have chins) won't fit into this as designed. IIRC Tom B had a picture of this with his head in it, and then Maximillians head - and it would only Fit Tom after major jaw reduction surgery.

Close sallets are one of the fiddliest projects possible - I think that JAG has some choice (and probably not suitable for print) things to say about reproducing them.

Scott

[Mac]

I think that this is one of the ones that was made for Maximillian, and most folks (who have chins) won't fit into this as designed. IIRC Tom B had a picture of this with his head in it, and then Maximillians head - and it would only Fit Tom after major jaw reduction surgery.

Close sallets are one of the fiddliest projects possible - I think that JAG has some choice (and probably not suitable for print) things to say about reproducing them.

Scott

I held with that rather uncomfortable opinion as well, until recently. It turns out though, that this and the other Helmschmeid closed sallet both work better if you assume that they get tipped back a bit on the head so that you mostly look out the breaths. The upshot here is that I think we have been misunderstanding these helmets.

Mac

[Indianer]

Hey guys :/

I need some advice on welding and don´t know any other place to ask. Couldn´t find anything on youtube for that small scale either

So I am trying to Mig-weld (flux-wire, polarities inverted accordingly) M4 nuts to angle irons, right onto the holes. The angle irons are 1/13th'' (~2mm) thick.

The nuts are galvanized, so I am wearing a mask.1) [see graphic] The screw is M4 too. I´d go with a smaller bolt instead to keep nut and bolt from sticking, but using an M4 screw lets me counter-nut it on the other side of the angle:

|| M4 screw
= M4 nut <- weld
------- angle <- here
_ Washer
= counter-nut
|| end of screw

- Trying to put the filler wire into the nook between plate and nut gets me nowhere. Eventually I burn the nut, but I won´t build up a weld puddle in the corner.
- I got a few nuts to stick by running 1/4'' bead from somewhere on the angle iron towards the nut. It´s solid, but the outcome is unreliable in terms of success or not. Plus, it's messy.

Anyone have pointers on how to do better, or suggestions on how to adjust 2) the machine?

Thank you guys. So long..

1) Putting the stuff in vinegar and removing the zinc coating causes the entire metal bodies to rust before I even brought it down into the basement for welding.

2) I mostly fiddle around with more or less heat, so a more shallow or more bulky weld.
Second option is adjusting for material thickness, which so farI tried from 1,8 to 2,2mm with less or, resp., more bulk. The thicker I choose the faster the wire feed.

[Scott]

I'm not sure that I am understand what the issue is that you are having. Is it that you are burning through the thin angle iron? I have issues with burn through when trying to weld to sheet metal using my wire-feed welder, especially thinner than 14#.

Here is how I would approach welding a nut to thinner metal. I would take a block of copper (like a piece of 12# or thicker) and drill a hole in it the same size as the hole in the target metal. Then I would put the bolt through the copper, then the metal, then the nut. Then weld the nut to the metal. The copper backing will help to prevent burning through the thin sheet.

Good luck!

- Scott

[Indianer]

Hi Scott,

indeed, I burn through pretty much everything - angle iron if I start some distance away from the nut, and nut...always. That doesn´t mean though that afterwards I had a weld between nut and bolt. They might be burnt, but sure not welded. For some miracle, even though the nut melts, the thread usually stays intact. I will make a pic of the few I got to stick...that´ll help.


EDIT -------------------------------------
So, first, I welded an M4 screw onto an M4 rod - good.

good 2.JPG (52.76 KiB) Viewed 26708 times

So I used about the same setting for the rest of the work..plus many deviations for tryout.

I tried to weld a long M5 nut onto the same M4 rod - bad.

bad 1.JPG (82.67 KiB) Viewed 27119 times

At some point, I get them to stick...but they are not centered then, which means I need to find a better jig to hold them in place. Anyway, the welds are thin, porous, and need many passes to become one thicker, solid joint, which involves manifold cleanups.

good 3.JPG (80.04 KiB) Viewed 27119 times

Even more shabby are the aforementioned angle irons...and this is one that got lucky. You see, iron plate melted where I ignited the arc, and - EDIT nut EDIT -molten where I dragged the puddle.[next post]