friendly conversation on A2 and chipping

[Jim Koepke]

I hope this adds to the discussion

Yes Chuck it does, particularly:

But there is a trade off. During heat treatment the chromium addition combines with some of the carbon in the alloy to form chromium carbides – tough, hard particles dispersed through the steel. These carbides are the primary contributors to A2’s celebrated edge retention. However, during heat treatment, the chromium carbides can grow quite large – large enough to affect your ability to hone the edge as close to zero-radius as you may want. And these carbides are held in place with less strength than the rest of the steel matrix which can allow them to pop out under the stress of honing or cutting leaving a small gap in the edge.

The part saying, "during heat treatment, the chromium carbides can grow quite large" opens up an area of inquiry.

They can grow... Does that mean sometimes they do not grow?

Is there still some mystery in the making of A2 or an area that is outside of human control?

Maybe there is a sweet spot in the process that has not yet been learned or maybe someone knows and isn't sharing.

jtk

[Kees Heiden]

So now we have plenty of indications that A2 can chip. Uddeholm sais so. Hock sais so. Plenty of users report problems. The reasons are the steel itself. The random patern of large chromium carbides make it unpredictable. Combine that with bogus certificates and dodgy suplliers. Heat treaters ain't all good boys either.

Buy A2 and take your chances. Or grind at a higher angle (not so great for chisels). Maybe we should forget about A2 alltogether especially now there is new steel on the market which promisses to be better. Anyone care to guess what PMV actually is? Knowledge of what is is might help to understand it better.

[Matthew N. Masail]

I honestly wish that someone would start making good old tough carbon steel blades like they used but with a modern like consistency which I'm sure can be done. Hock irons are great and all the ones I have perform the same, but they are HARD, not quite like the old steel.

[Tony Zaffuto]

I honestly wish that someone would start making good old tough carbon steel blades like they used but with a modern like consistency which I'm sure can be done. Hock irons are great and all the ones I have perform the same, but they are HARD, not quite like the old steel.

There are good old fashioned blades made! Ray Isles makes them (sold in the US-or used to be-by "Tools for Working Wood") is one. I believe Clifton in the UK still does.

As far as processing, if tool wrap is not used, a controlled/protective atmosphere is needed in the heat treat furnace and the composition of that atmosphere can affect final properties of the steel.

[ken hatch]

There are good old fashioned blades made! Ray Isles makes them (sold in the US-or used to be-by "Tools for Working Wood") is one. I believe Clifton in the UK still does.

As far as processing, if tool wrap is not used, a controlled/protective atmosphere is needed in the heat treat furnace and the composition of that atmosphere can affect final properties of the steel.

I would add LV for plane irons to that list.

[Matthew N. Masail]

LV O1 plane irons are very nice! still not the same stuff as a good vintage iron. The Ray Ils look good, anyone had an experience with them?

[Kees Heiden]

Yes, I have two Ray Iles O1 irons. In my #4 and my #6. In the 4 it performs perfectly allright. In the 6 which I use mostly on the shooting board I would like a bit more edge life. Sharpening them is uneventfull, I can't really feel much difference with the old Stanley irons. I sharpenede for a long time on waterstones but have now switched to oilstones.

But I don't think there is anything wrong with Hock O1 either which I have in a krenov type plane. Sharpens easy too. Chipping or folding isn't a problem with Ray Iles nor with Hock. They both know how to temper O1 steel.

[Derek Cohen]

There are good old fashioned blades made! Ray Isles makes them (sold in the US-or used to be-by "Tools for Working Wood") is one. I believe Clifton in the UK still does.

As far as processing, if tool wrap is not used, a controlled/protective atmosphere is needed in the heat treat furnace and the composition of that atmosphere can affect final properties of the steel.

I have done a bunch of plane and chisel blade tests over the years. One of the recent ones compared the LV Shooting plane (with 12 degree BU bed) and the LN #51 (with 45 degree bed). The LN used LN A2 blades at 25- and 30 degrees as well as a Clifton O1 (carbon steel) blade at 30 degrees. The LV used A2 at 25 degrees and PM-V11 at 25 degrees. Planing was controlled by the Stanley #52 shooting board, and the same hardwood was used for all tests.




Results are here: http://www.inthewoodshop.com/ToolRev...tingPlane.html

In summary, the BU blades simply outperformed the BD blades by a huge margin. The Clifton O1 blade came in dead last, also by a huge margin.

I really wanted to add a PM-V11 blade to the mix for the LN. When I did, it was apparent that the higher bed of the LN plane was a significant feature in the poorer performance of the blades. With a 25 degree bevel, the PM-V11 performed very poorly - less well than the A2 in the LN. However, with the bevel raised to 30 degrees, it performed on par with the 25 degree BU blade in the LV.

Conclusions are clear: all blade steels on a low bed are far superior in edge-holding and chip-resistance to blades in a higher bed. Higher bevel angles help in the latter setting.

There are also three studies comparing chisels on my website. The last one is probably more meaningful, where A2, PM-V11, O1 and White Steel were compared chopping dovetails: http://www.inthewoodshop.com/ToolRev...sCompared.html

Here PM-V11 and White Steel decimated the A2 and O1 steel.

Regards from Perth

Derek

[george wilson]

I am staying out of this debate since I have answered all the questions several times over the years. I have been hardening and tempering W1,A2,01 and D2 for over 40 years. Some for 50 years. I have listed the benefits and liabilities of these steels several times already. Except for powdered steels,when I want a good iron,I just make one.

Often,you just need to figure out how to sharpen these different steels to get the best results. I doubt that an LV or an LN iron is really going to be defective. If they chip,raise the bevel angle.

Matthew,you say you are doing everything by eye. Apparently not really gauging the angle you are sharpening at. Are you really sure of those angles? No insult intended,but from what you have said,I think you are a fairly new woodworker.

[Kees Heiden]

Cutting angle Derek, not bedding angle. The LN has a 45 degree bed, so the cutting angle is 45. The LV has a 12 degree bed and you sharpened the blades at 25 degrees, so you tested at 37.

I seem to remember that the LN A2 performed less well then the LV A2?

[Derek Cohen]

Hi Kees

I won't disagree with your interpretation. On the other hand, the two bed angles remain a constant, and one needs somehow to factor in the force vectors involved here. It is not the same as cutting angle, per se. That much became apparent when I looked at the effect of altering vectors by changing handle angles.

Regards from perth

Derek

[Kees Heiden]

That's about the ergonomics. It's about how it feels, and how effective your effort behind the handles is. Very legitimate stuff. But I don't yet see how that influences the movement of the steel through the wood, in a handplane. In a chisel the ergonomics and the user skill certainly influence the cutting action. But in a plane? With a reasonably skilled user? The iron is firmly attched in a solid construction pushed firmly again down on the wood. I think the cutting geometry of the edge is a lot more important.

[Brian Holcombe]

Have any of you guys tried the Tsunesaburo replacement blades? They are blue steel and iron....we get into alot of debates about A2 and so forth, but I never see much mention of this.

[Matthew N. Masail]

I am staying out of this debate since I have answered all the questions several times over the years. I have been hardening and tempering W1,A2,01 and D2 for over 40 years. Some for 50 years. I have listed the benefits and liabilities of these steels several times already. Except for powdered steels,when I want a good iron,I just make one.

Often,you just need to figure out how to sharpen these different steels to get the best results. I doubt that an LV or an LN iron is really going to be defective. If they chip,raise the bevel angle.

Matthew,you say you are doing everything by eye. Apparently not really gauging the angle you are sharpening at. Are you really sure of those angles? No insult intended,but from what you have said,I think you are a fairly new woodworker.

I'm sure, I have a few "devices" for checking. I don't got nuts about it, but within 1 or 2 degrees I am sure.

[Matthew N. Masail]

Have any of you guys tried the Tsunesaburo replacement blades? They are blue steel and iron....we get into alot of debates about A2 and so forth, but I never see much mention of this.

I got one. the one I have is fantastic for soft wood, holds up for a very long time and feel "slick" in the cut if that makes sense. works well for hardwoods too but it's not the same difference as when using softwoods. for Wenge I found a common stanley blade holds up better than the blue steel. only thing is that you can't grind them safely so in the future I'd get a hock iron or maybe try one of those Ray Il's.