Well used plane iron?

[pe2dave]

https://paulsellers.com/2022/10/rehardening-your-plane-iron/
Very useful (and complete) how to, on upping the hardness of your plane iron

 

[D_W]

Oh God, I'd be giddy to see the results his followers got from that with underhardened, overtempered and grown grain nonsense.

 

[Jorny]

For just the money spent on the torch he uses you get 5 or so replacement irons from Ray Isles. So the claim from Sellers that it is "economically still worth doing" is just plain weird.

 

[D_W]

For just the money spent on the torch he uses you get 5 or so replacement irons from Ray Isles. So the claim from Sellers that it is "economically still worth doing" is just plain weird.

there's a whole raft of little details that could make this whole thing successful if one is going to spend the money on a TS4000 and potentially house the heat and burn the igniter out of it willingly.

But, it's paul sellers. His throngs will go make some metal hot, have it unevenly heated, warpy, underheated and overtemper it.

The other part of this that's a false dilemma is that the average beginner is going to run across a bunch of half used plane irons and wear them out.

Lots of what he says here is factually incorrect, and others is the opposite of what you want to do - color temp viewing by eye in full outdoor light is absolutely the opposite and even the dippy challenge shows put guys outside when they're forging to confuse them.

But, it's paul sellers. complete with the dopey narrative about "the workers who just gotta pay the bills" as if this isn't a relatively high volume automated process.

"sally mcsofthands sits in a corner hardening and tempering one iron at a time, just like her grandpa did, and she's not a woodworker".

There is but one company that I can think of that hardened only part of an iron's length - Lie Nielsen when they were using water hardening steel and they couldn't control warpage (I could've done the work for them!!!...well, except I wasn't woodworking yet or doing any metal heat treatment).

The reality is, Paul is going to do a worse job than even the least expensive blanked plane irons that cost $2 each, and he's going to have his readers struggling to figure out why they can't get an iron to be well heated and evenly from edge to edge.

It would've been so easy to write this article about the same length, exclude the campy stories, the factual inaccuracies and give people something that would leave them with success.

 

[--Tom--]

Yeah but doing it properly would seem less accessible than warm it up with a blow torch and then dunk in some oil…..

Tempted to give plane iron making a go, feel that lapping it would be a bit of a pita without a surface grinder though

 

[D_W]

It's only a little different than what paul shows, but the parts that are different are critical.

I think with a torch, a steel can and slightly better understanding of metallurgy, it doesn't take much to match or better anything commercial. It doesn't take a person doing it long to learn it - in comparison to woodworking, is it easier to lay out and cut a neat mortise and tenon or harden steel properly? The latter is easier - but it's also easier to do a mediocre job and never figure out why.

W.r.t, your second sentence, everything always has a lot of nuances, but for the purpose of practical discussion if you don't want to go down rabbit holes, grind off most of the bevel on an iron, heat it at full heat only to the slot and get it into the oil evenly so it cools at an even rate and it will stay pretty flat. If you have steel or aluminum plates, you can make a three step quench - 5 seconds in quench oil, 10 seconds smashed in between flat plates and then finish the cooling in cold water or water and then toss in freezer. You'll have decent flatness that is easy to hand lap out and a very high initial hardness point which will lead to a better edge quality when it's tempered back and better long term stability.

The nuance part is the difference between various steels. I can't think of any practical reason for woodworkers to stray from good O1 steel, though. Once you get away from that to the water hardening side, to get really good results, you have to buy a fast quench oil and those are pricey.

The one thing paul got right is that the TS4000 torches are good. The part that he got wrong is that they make enough heat to evenly heat a whole iron out in the open.

Good quality O1, though, can be heated once a good bit past nonmagnetic quickly and quenched and it's 90% of what it will ever have the potential to be just doing that - if it's tempered accurately. toaster ovens have wide fluctuation in air temperature, so the iron needs to be stuck in between something that will absorb the ups and downs - could be a small container of pre-heated sand with the iron stuck in it, or between bits of steel or aluminum.

 

[Tony Zaffuto]

I don't want to disparage anyone moving our craft forward, however for Paul to encourage heat treating as a casual endeavor is just silly and can be potentially dangerous.

 

[Jacob]

I don't want to disparage anyone moving our craft forward, however for Paul to encourage heat treating as a casual endeavor is just silly and can be potentially dangerous.

Well you have to start somewhere and surely a casual endeavour is better than no endeavour at all!
Why dangerous, excepting obvious fire and burn risks?
n.b. I don't suppose he bought the expensive blow torch for just the one blade. Why not a cheaper propane torch, or are they not hot enough?

 

[D_W]

I don't want to disparage anyone moving our craft forward, however for Paul to encourage heat treating as a casual endeavor is just silly and can be potentially dangerous.

I wouldn't want to either. I think paul is promoting himself and worried more about keeping subscribers on his site than he is moving anything forward.

 

[--Tom--]

I’ve found 52100 with a DET cycle gives a more stable edge at low angles than O1. But that’s probably more noticeable at knife geometry than plane iron.
Challenge with doing DET is you get some decarb which would need lapping out.
Still have enough meat on my current irons to not need one. A year or two back I made an O1 iron for a record bullnose, as I needed one, that was still a pain to lap though.

 

[Jorny]

I would have a lot more respect for Sellers if he would just say: "I am not very good at this, so I do not try to teach anyone about subject xyz. You should check out this guy/gal, he/she knows how to do this." This is just like when he tries to make spoons or work with green wood. The results are terrible and it is clear that he is out of his depth.

 

[D_W]

I’ve found 52100 with a DET cycle gives a more stable edge at low angles than O1. But that’s probably more noticeable at knife geometry than plane iron.
Challenge with doing DET is you get some decarb which would need lapping out.
Still have enough meat on my current irons to not need one. A year or two back I made an O1 iron for a record bullnose, as I needed one, that was still a pain to lap though.

52100 has great toughness and fineness, and is more or less a different way to get to O1s wear resistance (that being slightly better than really plain water hardening steels).

But you'll find something really annoying with it in woodworking tools - as it wears, it enters the cut less easily. I have no idea why. The same thing is the case with chisels -side by side with a less tough chisel, and the less tough chisel will get through the wood in fewer strikes.

but take both of them and bend them, and the 52100 will dominate, which is why it makes great ball bearings and knives.

It'd make a terrible razor, though. It's baffled me - It's so tough that you can leave it almost completely untempered and plane with it, but the wear profile is still the same.

The three steels I've settled on for woodworking tools are O1, 80crV2 and 26c3 (pretty much chisels only, excellent hardness and decent toughness at high hardness, but very fast wearing in a plane iron - just like white steel).

If you post up a case when you make irons - in terms of what you're seeing and if there is a good quick way to hand lap, give me a heads up at that point. I usually spend about 10 minutes maximum lapping the back of an iron, cutting a bevel in from a zero bevel or close and polishing the back and honing. I've got a quirky setup that won't be very interesting to someone who only needs to flatten one or two irons.

A bullnose slater was literally my first plane iron, I still have the plane ,and the iron is fine, works well (starrett O1). That was on my mind as something people would succeed with starting - something that can be heated completely and evenly with one torch. A small marking knife or a bullnose iron, etc, is a great first shot.

 

[--Tom--]

Have you tried 52100 with a DET treatment first?

I see a lot of offhand comparison of steels, but HT has a big impact on end result. I could HT 52100 three different ways and it would seem like three different steels. Bit like the working characteristics of kiln dried vs air dried ash.

The steels you favour seem to have the most straightforward HT requirements, either a preference for lower alloying or challenges with getting everything into solution when using a forge for HT

 

[Tony Zaffuto]

Well you have to start somewhere and surely a casual endeavour is better than no endeavour at all!
Why dangerous, excepting obvious fire and burn risks?
n.b. I don't suppose he bought the expensive blow torch for just the one blade. Why not a cheaper propane torch, or are they not hot enough?

Jacob,

I own a powder metal manufacturing plant and though I know a fair bit about heat treating, I prefer not to engage process discussions. A few years back, a neighboring plant had an employee critically injured from a D2 tool that was heat treated improperly as well as not drawn back. The tool shattered like glass.

If a craftsman wants to learn/undertake home heat treating, small forges as available and with your wife’s toaster oven to draw, a decent job can be done.

For a quick look at my plant, google “metaltech-pm.com” (I’m sole owner). Bear in mind the website has not been updated in 4 years. Since that time, I have added three robots and a fully automated cell. Still interested in this industry, google “gasbarre.com”. That’s my son-in-laws company. He’s CEO, and that’s their family business. If looking, search the portion of their site for “gasbarre thermodynamics”. They are the largest comprehensive manufacturer of powder metal process equipment in the world.

T.Z.

 

[Homeless Squirrel]

I wouldn't want to either. I think paul is promoting himself and worried more about keeping subscribers on his site than he is moving anything forward.

"YouTube" which about say's it all as way too many Wanna be's trying to flog there soul on there trying to keep up with YouTube's garbage system with ranking/points and cash and you end up with just YouTubers playing to the Camera instead of any Quality info.
Have many doing Sea Fishing stuff end up being a waste watching

 

[Jacob]

"YouTube" which about say's it all as way too many Wanna be's trying to flog there soul on there trying to keep up with YouTube's garbage system with ranking/points and cash and you end up with just YouTubers playing to the Camera instead of any Quality info.
Have many doing Sea Fishing stuff end up being a waste watching

Well yes very true. But I don't think Sellars is as bad as many. He is generally very practical and debunks the fantasy woodwork gurus. His design work is a bit cr*ap and he doesn't know how to use oval bolster mortice chisels, but nobody's perfect!
I really don't think his heated plane blade is likely to shatter and cause injury.
Might even be worth a go though I've never felt the need. Most likely outcome it'd be worse than it was before, but it's a learning curve!

 

[D_W]

Have you tried 52100 with a DET treatment first?

I see a lot of offhand comparison of steels, but HT has a big impact on end result. I could HT 52100 three different ways and it would seem like three different steels. Bit like the working characteristics of kiln dried vs air dried ash.

The steels you favour seem to have the most straightforward HT requirements, either a preference for lower alloying or challenges with getting everything into solution when using a forge for HT

Yes. As far as I know, DET generally gets things away from a spheroidized - or at least coarse spheroidized condition that's easy to machine but doesn't result in good hardness on a standard schedule.

I've tried about 6 different things with 52100. If you treat it like you're ignoring the chromium, it will come up short in hardness. Not like a stainless but sort of the same type of thing - it's probably a matter of getting some of the carbon in solution before hardening. Once you solve that, it'll get to very high hardness without having to undertemper it, but it still has the same initial sharpness that O1 does but the very edge wears in a different pattern.

I thought AEB-L might be nice and wear really finely, but it does the same thing a little bit. These things don't matter on knives, so I think AEB-L is the bees knees for a basic stainless knife that needs to be in the chisel hardness range. I won't delve far into what I did to get high hardness out of it other than to say pre-quench, a lot of heat and a very short very high heat in the open atmosphere and a quick quench. 52100 likes the same thing.

For someone working from a garage, to dissolve chromium carbides without a furnace, it's probably better just to find bar stock that's not delivered coarse spheroidized like buderus and some other mills deliver it.

As far as the steels that I like ending up being simple, I wish AEB-L did better. It's actually quicker for me to heat treat than most carbon steels because it doesn't get any normalizing heats or grain refinement. Just a prequench probably around 1800F and then a higher heat and a fast quench. It definitely wears longer than 80crv2 and O1, but like 52100, it doesn't pick up a shaving as easily in fine work.

To see what i'm talking about, you have to make two irons for the same plane and then do a durability test. If they are about same hardness and last the same number of feet and plane the same weight, they're in good shape for comparison. But as you get into their dullness cycle, you'll notice that O1 picks up a shaving more easily. They both fall off the cliff at the end and stop cutting. A2 also has this behavior, but it has a little bit more edge life - I would describe it as longer wearing than O1, but the period of longer wear is one that you don't want to use, anyway.

I wouldn't have noticed any of this (I thought AEB-L once I solved getting it above 60 was going to be a real charm - and it does have good wear and the images of it show almost no visible carbides at all).

80crV2 is just a better 1084. 1084 is easy to heat treat once you narrow down what stops grain growth, there's less tolerance for heat and time, but that's not much of a problem - when you're at the forge, the faster you can go paying attention, the easier it is to pay attention. 80crV2 warps less, wears longer and so far as I can tell, there's nothing better about a tool with 1084 vs. 80crV2 aside from perhaps if you wanted to explore the outer reaches of hardness, 1084 may get a point harder.

All of this is way above the head of the sellers article, but partially explains why I settled on three easier steels after chasing "less easy steels". The three I like seem to return good edge quality throughout the wear cycle - 26c3 in chisels (does fine in planes, but I can't see a reason to use it unless someone wants a 65/66 plane iron - which again, I don't see the benefit of other than novelty), 80crv2 and O1 in chisels. I can make a passable chisel in O1, but 26c3 is at least a notch better.

-------------------------

too with AEB-L - the toughness is really high. It will deflect an edge a little at high hardness (like 52100), and so will 80crv2 at the initial edge. That's a habit in wood that I don't really like. On a knife, it's probably preferable. So I leave 80crv2 at a harder temper, and the same with AEB-L. They do well at 325-350. O1 and 26c3 do not in woodworking tools.

 

[D_W]

TLDR on the steel above w.r.t. paul's article. It's possible to avoid all of that stuff, find a steel or type of plane iron and come up with literally a one or two step process with much better results than paul gets without having to learn much.

O1 would be preferable because it can fully harden at a slower transition than some of the vintage stuff. 1084 is often suggested if you ask someone who makes knives, but 1084 itself can have wildy uncontrolled grain growth very quickly and it needs to quench really fast (veg oil won't do it, and water will result in cracking) and have a cold tail quickly (more warp potential) to get to good hardness. It's probably similar to the steel in a lot of laminated irons, though.

 

[D_W]

Well yes very true. But I don't think Sellars is as bad as many. He is generally very practical and debunks the fantasy woodwork gurus. His design work is a bit cr*ap and he doesn't know how to use oval bolster mortice chisels, but nobody's perfect!
I really don't think his heated plane blade is likely to shatter and cause injury.
Might even be worth a go though I've never felt the need. Most likely outcome it'd be worse than it was before, but it's a learning curve!

Paul sellers is the "i'm not very good, but there are worse than me who will sell you stuff - I just want you to pay my site because why would I want to push tools and only get part of it" kind of guy.

You could get an even match for the factory heat treat on your first try with the right instructions. Paul's aren't the right instructions.

You can better factory heat treat within a few tries, but it's like anything else, you have to be willing to understand what's going on and observe results.

I suspect paul has hit or miss results at best and doesn't scrutinize his plane irons, and the campy story about people at the factory not caring might've been the case for late marples, but it's off the mark in almost every other case. The OWT that heat treat is inconsistent on older tools is based on limited experience. It differs from one manufacturer to the next, but not much within manufacturers during the same time period.

Marples mentioned because they are the only tools I've ever gotten where tools have arrived unhardened. But never in the older ones. It take a huge miss for that to occur - like the quenching step on an induction heating line has no water running through it and nobody cares, nor does anyone notice anything in grinding because the grinding is done by a machine instead of by a job grinder (who would've thrown anything that grinds like butter in a bucket for junk or redo).

I've never had a stanley iron that wasn't properly heat treated, and I couldn't say with any honesty that I've ever had a modern bench plane iron that wasn't hardened very close to all the way to the slot. Lie Nielsen story relayed from the CW toolmaker where they do actually use hand tools, and when they got halfway through the irons, LN relayed that warpage was a problem hardening the entire length of the back and they didn't think anyone would generally get to that point. With their typical customer (me included) they're probably right. That issue is history since they moved to A2, which is a favorite of toolmakers because it doesn't move much.

 

[D_W]

Torch question from above about TS4000 vs. anything else. The TS4000 torch is sort of mid output and high temperature. It does get a hotter flame than most other torch types. Some are smaller (and maybe get as hot) and some push more gas through the tip but don't make a flame as hot. if you're going to heat treat something, you want a small shelter to house the heat and you want as much point heat as you can get at an acceptable volume so that you aren't slowly bringing steel up to temperature in the open atmosphere.

I've got a separate "proper" double top burner stainless forge, which will make 10 times as much heat or more than TS4000 tips, but it will not get as hot.