New batch of old axes (ID help request: Säter, DY)

[Square_peg]

These transitions can show metal changes (high carbon bit), heat changes from the quenching/tempering process or both. I have some ideas about the curve that I will share later.

Please do.

quare_peg,as you know i've an unwholesome obsession with this subject...Really looking forward to what you may come up with.

Jake, I think you've heard my hypothesis before and disagreed with it. And I respect your opinion on these things greatly so I'm likely wrong. But until I hear a better explanation I will continue to believe this. Science loves to be proven wrong and so do I.

Some of these curved lines are steel transitions. But others are a quench line. So how does a dip into a level body of quenchant result in a curved line? It's my opinion that residual heat in the head spreads out from the unquenched portion of the head. The center, being thickest, holds the most residual heat. This center heat is able to spread further back toward the bit, resulting in the curved line we see.

 

[ithinkverydeeply]

I do not claim to know anything at all about metallurgy or tempering but I thought it was something happening with the steel’s carbon near the surface of the tempered area...
Or was that what happens in a vinegar bath...
Where did I read that..?

 

[Fmont]

Jake, I think you've heard my hypothesis before and disagreed with it. And I respect your opinion on these things greatly so I'm likely wrong. But until I hear a better explanation I will continue to believe this. Science loves to be proven wrong and so do I.

Some of these curved lines are steel transitions. But others are a quench line. So how does a dip into a level body of quenchant result in a curved line? It's my opinion that residual heat in the head spreads out from the unquenched portion of the head. The center, being thickest, holds the most residual heat. This center heat is able to spread further back toward the bit, resulting in the curved line we see.

It's probably that and the fact there's more surface area of thin steel at the heel and toe. The quenchant is cooling up the sides as well as the front.

Either way, it seems to me a less than desirable heat treat. Perhaps the result of an abrupt process.

 

[Downwindtracker2]

I don't know anything about tempering axes, but I worked in a wire mill, we had three lead baths.We used liquid lead for washing, cooling, and annealing . The lead pans were at different temperatures. I suspect square peg's explanation is on the right track. They were likely using a higher temperature lead and dipping quickly to improve production. Nadex are using a single heat treatment and is able to sell their chisels at an affordable price compared to the double dip. It's that costly a process. So there would be incentive to speed up. This is just a W.A. guess.

 

[Ragnar Ökman]

According to Square_peg´s center heat theory phantom beveled heads and splitting heads with high rised concave cheeks should show tighter curves than flat wedge heads (material and heat treatment being the same). Do they?

 

[jake pogg]

Uhm...You guys all bring up some interesting points...The trouble is,the fact that it's Curved is not really that significant.
Uneven heating can be achieved in a number of ways,an induction coil is one;also uneven cooling(high-temperature salts,say).
The main question remains:Why would an acidic etch show contrast between Phases?!
Etching,normally,reflects the Carbon content,the more/darker.
So Why would all of a sudden the etch-line(of whatever curvature) reflect Phase Transformation?
And show it as darker area?

 

[jake pogg]

On a slightly different subject...Ragnar mentions an interesting concept,re-blading worn old axe-heads with some sexyl modern alloy...

Re-blading in general is something that any axe-freak community would,you'd think,discuss by now....But it's SO far back in the past,practicality-wise,that it hardly ever even comes up.

I've considered doing some of it,but it's just too much work for my "one-armed" operation...American axes(and that Sater is styled after them too)are too much mass for me to handle efficiently.
(That video from Norwegian Traditional crafts series really shows how much energy is required for the more/less traditional approach,that man uses a striker And an arc welder AND a PH as well....).

So,over the years i've had some ideas...One of them is as follows...
Photo:https://imgur.com/AN80AE1

It is a dozer track that had an ice grouser welded onto it using stainless rod.
Note how Sound is that weld(though it doesn't even meet,at the root).When that track broke,it broke the grouser along with it,the weld withstood a Very significant stress.

What if a guy attached a new blade to an existing,worthwhile old eye,by just such means?
Then it can be forged Or machined,and HT'd,and be restored to full functionality at no great energy+labor+tool-intensive expenditure.
And have that cool stainless stripe across it!

 

[Square_peg]

The main question remains:Why would an acidic etch show contrast between Phases?!
Etching,normally,reflects the Carbon content,the more/darker.
So Why would all of a sudden the etch-line(of whatever curvature) reflect Phase Transformation?
And show it as darker area?

I can't say why. But we see these curved lines even in Plumb mono-steel axes where it can't be showing a contrasting steel. And we sometimes see 2 curves, one showing contrasting steel and the other presumably related to the heat treat.

 

[Square_peg]

What if a guy attached a new blade to an existing,worthwhile old eye,by just such means?
Then it can be forged Or machined,and HT'd,and be restored to full functionality at no great energy+labor+tool-intensive expenditure.
And have that cool stainless stripe across it!

Should work. And it would save a lot of coal.

 

[jake pogg]

I can't say why. But we see these curved lines even in Plumb mono-steel axes where it can't be showing a contrasting steel. And we sometimes see 2 curves, one showing contrasting steel and the other presumably related to the heat treat.

Yes,it's a mystery......I'd just like to emphasize that under NO circumstances i'm denying the possibility of that effect.
Actually i have zero knowledge of metallurgy on this(or any otherlevel.
I did ask around some very informed folks though,and the only feedback was puzzlement,no one can say why it would be so.

Should work. And it would save a lot of coal.

Yessir.And actually Any forging can be avoided,by shaping the bit before fabrication,by Reduction alone,and once joined it'll likewise only require machining.
And,since Ragnar brought this up in regards to exotics,if one used some funky air-hardening alloy like A-series et c.,you'd possibly not have to HT it either,after such a massive arc-weld so close to the edge of the blade...
(sharpening it afterwards being another story

 

[crbnSteeladdict]

On a slightly different subject...Ragnar mentions an interesting concept,re-blading worn old axe-heads with some sexyl modern alloy...

Re-blading in general is something that any axe-freak community would,you'd think,discuss by now....But it's SO far back in the past,practicality-wise,that it hardly ever even comes up.

I've considered doing some of it,but it's just too much work for my "one-armed" operation...American axes(and that Sater is styled after them too)are too much mass for me to handle efficiently.
(That video from Norwegian Traditional crafts series really shows how much energy is required for the more/less traditional approach,that man uses a striker And an arc welder AND a PH as well....).

So,over the years i've had some ideas...One of them is as follows...
Photo:https://imgur.com/AN80AE1

It is a dozer track that had an ice grouser welded onto it using stainless rod.
Note how Sound is that weld(though it doesn't even meet,at the root).When that track broke,it broke the grouser along with it,the weld withstood a Very significant stress.

What if a guy attached a new blade to an existing,worthwhile old eye,by just such means?
Then it can be forged Or machined,and HT'd,and be restored to full functionality at no great energy+labor+tool-intensive expenditure.
And have that cool stainless stripe across it!

In late 30-ties Kelly Perfects had electrically welded bits (not sure it those were inserts or resembled Vaughan's diagram)

From 1940 Vaughan catalog: Electric Fusion Process used to weld the pieces together

https://archive.org/details/SimmonsKeenKutterCatalog1939Part/page/n145
https://archive.org/details/VaughanFineTools1940/page/n5

 

[jake pogg]

That is Very cool info,thanks for that

(it may even have a bearing on that other subject,the "temper" line...)

 

[Ragnar Ökman]

Google gives us 528 page .pdf named Phase Transformations in Metals and Alloys (2. ed. 1992). I can´t take that much science even if it was in Finnish. It does not contain words etch or acid, but maybe it holds the secret.

I was thinking laser or electron beam welding or other low heat joining for already heat treated and finished super alloy blade bit. But then common sense and limited income always ruins these kinds of ideas.
I contacted a few local smiths about traditional re-steeling. At least one is familiar with it. Waiting for details.

 

[garry3]

In late 30-ties Kelly Perfects had electrically welded bits (not sure it those were inserts or resembled Vaughan's diagram)

From 1940 Vaughan catalog: Electric Fusion Process used to weld the pieces together

https://archive.org/details/SimmonsKeenKutterCatalog1939Part/page/n145
https://archive.org/details/VaughanFineTools1940/page/n5

That Vaughan weld is what I must have seen at a second hand store this winter. It looked like a TT boys axe, no stamp, red paint. Had the snot beat out of it with a deformed eye and it was coming apart at the weld just in front of the eye.The joint was kind of keyed if I remember right. They wanted more than it was worth and I went back that weekend just to get a picture and some one bought it.

 

[jake pogg]

Google gives us 528 page .pdf named Phase Transformations in Metals and Alloys (2. ed. 1992). I can´t take that much science even if it was in Finnish. It does not contain words etch or acid, but maybe it holds the secret.

Ragnar,since i was the one who brought in the weird terms,i'll try to put it simply:
When we choose to harden steel we Thermo-cycle it in a given way.
In the process of heating and cooling steel undergoes changes,going through so-called Phases,which in turn affect the micro-structure of steel.

With Carbon steel the common desired state is called Martensite,it's a Phase that allowed the steel to accommodate more Carbon atoms inside the structure,making it denser(we call this Hardness).

Martensite is arrested by rapid cooling(quench)and so the changes to the micro-structure remain permanent.

Science is actually kinda undecided if Martensite is a Phase,a structure,or both,and so i was wrong to use the term Phase Transformation.Phases Cause the changes to the micro-structure,and that's what we're interested in.

So,the "temper-line" would exist if indeed we could see the difference in micro-structures,between differentially heat-treated portions of an axe.
Could do so with a naked eye,maybe with the help of an etch,et c.

Indeed,such thing can be.Under very high degree of polish we Can indeed see some things there.Under Uber High polish,like in the Japanese tradition,going into tens of thousands of grit,things get real interesting
But,none of them look like an axe blade(generally, hardened areaslook lighter in color and of course glossier,being denser taking higher gloss).

And,we're talking wire-brush finish on surface...AND,very mildly acidic etches...(knifemakers labor at it with things like Nitric and other intense acids).

So,a number of things do not quite compute.
But they instantly fall into place if there's a joint between two dissimilar alloys.
Presence of Carbon in alloy responds to etching immediately and very starkly.And since it's for that difference that we'd likely use that method,to have a hardenable edge...

But metallurgy is a mystery still,and sometimes hardened steel Does etch dark......

This is to quickly recap for you some previous discussions,sorry if it's longwinded...

 

[jake pogg]

think this is a case of that patented electric weld coming apart..
.https://www.ebay.com/itm/Vintage-An...121313?hash=item3408fd5c21:g:5egAAOSwxL1cu0xj

(caused perhaps by that freeze-damage cracking the eye?)

Sorry if this link somehow not ok for the forum,i dunno how to make a screen-shot...

I must say i'm impressed,this weld,done howsoever-electrically or otherwise,is a diffusion weld(forge-weld,vs an arc,or other kinds that liquify steel).
As such there's always a dissimilar structural boundary,and in testing such weld will Always part right along that boundary.
That's why normally forge-weld is positioned to take advantage of Shear forces(it resists those best),as well as it's area gets maximized by scarfing.
In that Hand-made above the weld seams are totally minimal for diffusion welding,they musta been Good,to have so few of them come apart...
(it must've been akin to today's technology where they spin sections of pipeline against each other to fuse the ends,forge-welding using friction...)

 

[Ragnar Ökman]

That is an interesting find and a good point on scarfing.
I got one reply (only one so far) on renewal of the Säter head from a blacksmith nearby. He offered to MIG-weld some spring steel for the new edge and abrasion resistant (HARDOX) steel to the poll. Said it would be stronger than forge weld due to less carbon loss. Waiting time till August and estimated price 130 €, so it´s not going to happen.

 

[jake pogg]

Yes,Ragnar,things are tough in Finland too...Axe-culture is receeding into the past everywhere,someday probably car parts and filling stations will be as scarce...

One thing i'd argue with that man about is the loss of Carbon.
Even at such high temperatures as welding,diffusion of elements takes quite a long time!
So if you're forge-welding a high-carbon bit onto a lower-C body,in whatever minutes that the weld stays at high-enough T some carbon indeed will diffuse across the weld-boundary into the body(solid elements,like gases,equalize,go from more to less).But that doesn't affect the axe in any way no matter what

Meanwhile,the outside of the steel that's exposed to the heat AND Oxygen,will not only loose carbon,it'll change completely into some form of oxide of iron...(aka forge-scale.
But even that effect penetrates only several 0.001"...A layer that a good firm stroke of a file takes right off.

You seem to be good at machining...Do you think you could mill an overlaid-type bit for the Sater,to be mechanically attached,like excavator teeth inserts?

 

[Ragnar Ökman]

It has crossed my mind to make a changeable edge piece for axe head. But there must be a reason you don´t see many striking tools of that kind. Maybe they break too easily or are too expensive to manufacture.
I have made a couple of knives out of flat bar AISI M-1 HSS. No need to forge, just grind away and send to heat treatment. It could work. Tight tolerance tongue and groove joint with cross pins or dovetail joint and press/friction/thermal fit.

 

[jake pogg]

Seems like i even remember something of the sort Done,in the world of "techy-contraption-y" axes...vaguely...
An axe is a tool ancient and very well distilled in it's engineering...I don't think the loads on the bit are That great,most moment would be in a direction very favorable to the joint.
I'd not be surprised if an accurately executed simple wedge-shaped joint(body male/bit female,to keep softer body from wobbling out),of some legit Morse-taper-ish proportions,would work pretty much on it's own...(maybe a small tapered pin for safety...)...