O1 vs. A2 steel preferences

[Dustin Irby]

I'm getting ready to purchase a LV BU Jointer and was wondering if there's a huge advantage between an O1 vs. A2 steel blade. I currently sharpen with Norton water stones, so don't know if there is an issue there. Any advice/opinions are welcome. Thanks!

[Wayne Morley]

No there is not a huge advantage for either steel, both are good. There are however tradeoffs. It is generally accepted that the A2 steel will stay sharp longer than the O1 with the tradeoff that it is a bit harder to sharpen. The toughness of the A2 steel is in part due to carbide crystals in the grain structure, but the tradeoff is that the crystals tend to break off when the edge is sharpened at less than about 30 degrees.

Your Norton stones are up to the task of sharpening both steels, so this is not a consideration. The cost is the same for both, so this is not a factor.

Given the tradeoffs I would choose the O1 steel, because it will give you more versatility in selecting a bevel angle. This versatility is part of what makes the BU configuration attractive.

Of course opinions will vary.

[David Weaver]

The quality of the steel and the heat treatment in one vs. the other is more important than the type.

A good A2 iron will stay sharp for a very long time and surprise you with its toughness. A not so good one will lose large carbides and leave lines on your work long before the rest of the edge is dull.

A good high carbon steel iron that's nice and hard will also wear a long time, and the edge will wear in a way that leaves a nice surface, even as it gets duller.

[Don Dorn]

Interesting question - not sure I have a difinitive answer, but most of my planes are A2 because they came that way. They sharpen easier than I thought they would. For the two Stanley planes I have, I use Hock irons that are O1. They sharpen very easily and stay that way far longer than I thought. I also bought a LV Low Angle Smoother years ago and chose O1 and again, sharpens easy and keeps an edge along time. Therefore, when I took delivery of my new LV BU Jointer about two weeks ago, I ordered it with O1. I didn't want to mess with what works - it sharpened perfectly and quickly - and I'm very impressed with it's performance. It gives nearly transparant shavings (not that I want that very often) that make me smile every time.

If you look at the hardness, O1 is pitched to be 58-60 and A2 is 60-62. Therefore, at the extremes, an O1 blade is about 94% as hard as the A2. That explains to me why they keep an edge so well. I think many have talked themselves into believing that O1 is "soft" and A2 is "hard". Good luck and let us know which way you go.

[Tim Put]

Rockwell Hardness is not so simple and not so linear. It's is neither correct nor infact particular coherent to say that 01 is "94%" as hard as A2.

Further, I find the difficulties of A2 and low bevel angles to be exaggerated. I have a 25 degree LV A2 iron, when new I did have chipping troubles, but after a couple of grinds (probably less than 0.01") they stopped.

That said, there's nothing wrong with O1.

[David Weaver]

In my anecdotal experience, I would call 62 hardness "twice as hard" for edge holding purposes as is 58 hardness - at least.

It should also be noted that terminal hardness for O1 is in the 66 or 68 range or something. It works very well in the low 60s if it's good quality steel.

LV could easily make the HCS the same hardness as the A2, but I would think that people who have arkansas stones would probably complain, and those of us who use aluminum oxide, diamond or ceramic based abrasives wouldn't probably notice the difference in how fast the HCS vs. the A2 sharpens.

I'm pretty well convinced that anyone who doesn't like A2 for sharpening:
* may be using stones that can't cut the carbides
* wouldn't be that excited about sharpening the very hard high carbon steel blades, either.

but that's just an assumption, and you know what they say about those.

[Derek Cohen]

I'm pretty well convinced that anyone who doesn't like A2 for sharpening:
* may be using stones that can't cut the carbides
* wouldn't be that excited about sharpening the very hard high carbon steel blades, either.

David, I think you are on the right track there.

I do think that the choice between O1 and A2 will come down to (a) the wood you tend to use most (whether the wood is more abrasive than average) and (b) how good you are at sharpening.

In my experience O1 and A2 get equally sharp. Depending on your honing media and stratregy, A2 does not have to take more than a little extra effort, but you are repaid with a longer edge holding. I tend to use Shaptons and hone microbevels, which works very well.

The angle at which A2 is best honed is not an issue with a BU jointer plane since you will be aiming for about 35-50 degrees. In any event I have used A2 at 25 degrees for years on a shootingboard withoutr any issues about edge retention.

I tend to gravitate towards A2 because of our local woods being hard and high in silica, which makes them more abrasive and hard on blades. That is my situation and yours may be different. I guess if I worked softwoods only, and used oilstones only I would question the use of A2.

Regards from Perth

Derek

[Steve Dallas]

I'm getting ready to purchase a LV BU Jointer and was wondering if there's a huge advantage between an O1 vs. A2 steel blade. I currently sharpen with Norton water stones, so don't know if there is an issue there. Any advice/opinions are welcome. Thanks!

The choice between A2 and O1 is an artificial one.

If you have a bona fide need, why stop at A2? Kunz makes cutters for Bailey pattern planes in HSS. ECE makes HSS cutters for its planes as well. These steels check out around 62 to 64 Rockwell and are extremely abrasion resistant. One shouldn't let one's affection for a pet tool supplier influence their choice if there is a real need for a tool steel to hold up to unusually tough species. A2 or O1 will get you through a couple of projects a year, no sweat; buy either one and don't worry about it. If you are really into the craft, like to work hard, have an affinity for tropicals, I'd build my bench plane arsenal around tools for which HSS cutters are available. To me, it's less an issue with chisels but your 4, 5, and 7 will really take a beating if you are totally getting after it on a regular basis.

Stanley and Record also used to manufacture HSS cutters for their customer base in Australia and New Zealand. Kunz and ECE have not forgotten those woodworkers, but you can buy these here in the States as well. Poseur warning: they are not cheap, nor that sexy, nor particularly photogenic.

[David Weaver]

Kunz makes cutters for Bailey style planes in HSS.

Eh? I guess you can't really post a link. I'll go google.

[Dale Sautter]

If you have a bona fide need, why stop at A2? ...

Or CPM-3V if you're up to it. John Payne01, the guy here who makes those "Unbelievable New Chisels (http://www.sawmillcreek.org/showthread.php?t=140221)" said that 3V was coming for plane irons soon too, here (http://www.sawmillcreek.org/showpost.php?p=1426277&postcount=34), so you may want to send him a PM to inquire. He sold me a 2" wide D2 iron for like $25... tough stuff... 3V is even tougher. Last week I used diamond powder/paste to lap 3 CPM-3V irons (that I purchased elswhere) and John's D2 iron. One of the 3V irons will be honed @ 20 degrees for a low angle application... I just wouldn't try that with A2. Anyway... fwiw... ;)

[Steve Dallas]

Eh? I guess you can't really post a link. I'll go google.

Traditional Woodworker in the US and many, many suppliers in Europe (most probably don't have websites). I'm surprised more people aren't aware of the availability or even the existence of these cutters. "Drop the Lee Valley catalog and Move Away" comes to mind. Whole big world of woodworking out there - don't let the guys shilling on the internet for their favorite supplier shrink your world.

http://www.traditionalwoodworker.com/index.php

Go to the Kunz bench planes and then click on the replacement cutter links.

They carry the HSS replacement cutters for a couple of ECE planes as well. In Germany, the full line used to be available in HSS, though I think they still do HSS for the full bench plane line.

Last time I was 'down under' , less than two years ago, the used tool dealers had scads of the Stanley HSS cutters available. They're there.

[David Weaver]

Traditional Woodworker in the US and many, many suppliers in Europe (most probably don't have websites). I'm surprised more people aren't aware of the availability or even the existence of these cutters. "Drop the Lee Valley catalog and Move Away" comes to mind. Whole big world of woodworking out there - don't let the guys shilling on the internet for their favorite supplier shrink your world.

http://www.traditionalwoodworker.com/index.php

Go to the Kunz bench planes and then click on the replacement cutter links.

They carry the HSS replacement cutters for a couple of ECE planes as well. In Germany, the full line used to be available in HSS, though I think they still do HSS for the full bench plane line.

Last time I was 'down under' , less than two years ago, the used tool dealers had scads of the Stanley HSS cutters available. They're there.

I don't think most people on here have such a problem with "one supplier". I sure don't, I've just got enough experience with kunz stuff to realize most of it isn't worth the raw materials it was made from, and never would've thought of them for HSS. There's no reason to take a slap at people or suppliers when they're not exactly selling junk.

And sheesh...100 bucks? For something from Kunz? Wouldn't dream of it unless I heard someone else was supplying it to them.

You can get an entire full-sized ebony or ironwood continental smoother with an HSS iron from mujingfang for $50, and from personal experience, it is *very well* made. That knocks emmerich out, too. If muji ever decides to reorient the slot in their bench plane irons, it'll be all over.

I recall the ASW blades being about $100-120 when they were available, and there were M2 irons on the aussie ww forum for about $50 plus shipping IIRC - and thick, too.

I only perked up because I thought coming from kunz, they might be reasonably priced, especially given the kunz reputation for tools *much worse* than any stanley types, except maybe rivaled only by the plastic handled stanley planes.

[Derek Cohen]

I can amplify the point about the Mujingfang HSS blade. I bought one locally for about $20 and, althought designed for a woodie, it fits my Stanley #3 perfectly. Excellent blade.

Regards from Perth

Derek

[Steve Dallas]

I don't think most people on here have such a problem with "one supplier". I sure don't, I've just got enough experience with kunz stuff to realize most of it isn't worth the raw materials it was made from, and never would've thought of them for HSS. There's no reason to take a slap at people or suppliers when they're not exactly selling junk.

And sheesh...100 bucks? For something from Kunz? Wouldn't dream of it unless I heard someone else was supplying it to them.

You can get an entire full-sized ebony or ironwood continental smoother with an HSS iron from mujingfang for $50, and from personal experience, it is *very well* made. That knocks emmerich out, too. If muji ever decides to reorient the slot in their bench plane irons, it'll be all over.

I recall the ASW blades being about $100-120 when they were available, and there were M2 irons on the aussie ww forum for about $50 plus shipping IIRC - and thick, too.

I only perked up because I thought coming from kunz, they might be reasonably priced, especially given the kunz reputation for tools *much worse* than any stanley types, except maybe rivaled only by the plastic handled stanley planes.

Whatever. I mentioned two manufacturers - Kunz and ECE. HSS from either one is fairly pricey. It is what it is.

If you need them you now know where to find them.

[Dustin Irby]

Well, thanks for the help folks. I can always depend on knowledgeable responses here. I plan to be doing most work in oak, poplar, cherry, walnut and pine. I decided to go with the O1 since I don't consider myself an expert sharpener... yet. I'm sure I'll end up trying the A2 or some other steel eventually.

[george wilson]

Last week I had to skive down some really tough and soft sea ray skin(also known as shagreen) I have planed down leather before when I needed it very thin. This skin was chrome tanned,and very difficult to skive. I used my LN block plane to skive it. I have both an 01 and an A2 blade for the LN plane. I couldn't quite get the A2 blade sharp enough to plane the spongy leather,but was able to get the 01 blade sharp enough to do it.

This was a demanding job for any steel to cut. I had even taken it down to the book binder's shop in Williamsburg,where my friend Bruce is the master. He has a special skiving jig made in Germany,that uses razor blades to skive leather. It wasn't doing too well either on this leather.

This is an example that shows that 01 will get sharper than A2. I had wished that I had a blade made of 1095 water hardening steel for this job. It will get the sharpest of all. Maybe I'll make a blade of 1095 for this plane. Thing is,the sharper the blade can get,the least time it will retain that edge,it seems.

[Larry Williams]

If it's an older LN blade, it is 1095.

[Tim Put]

I couldn't quite get the A2 blade sharp enough to plane the spongy leather,but was able to get the 01 blade sharp enough to do it.
...
This is an example that shows that 01 will get sharper than A2.

Not quite. What it shows is that with your (primarily aluminum oxide based; "ceramic" stone followed by Simichrome MSDS (http://www.gesswein.com/catalog/techinfo/msds/pdfs/Simichrome_Polish.pdf)) sharpening methods, O1 will get sharper. Simply put, chromium carbide (and vanadium, tungsten, titanium and silicon carbides) are harder than the abrasive you're using to sharpen them. If you want A2, M2, CPM-3V or any other high alloy steel as sharp as O1, you need to use at minimum CrO2, or better still, diamond.

[george wilson]

The guys at LN told me the blade was 01. I called them about another matter.