is all A2 created equal? and how do you regrind?

[David Wadstrup]

Hello,

I am relatively new to woodworking, and new to sharpening woodworking tools. Because of the kind of work that I've been doing over the past few months, I've only really been using handplanes. And, subsequently, my sharpening has been limited to their blades. Veritas' A2 blades to be specific. It was only last week that my chisel work has started to pick up, and hence, the need to sharpen them. What a difference! The sharpening of them is so much more butter-y, for lack of a better word. I'm able to bring up a burr almost effortlessly, and the sharpness of the blade is obvious. Why is this is not the case on my Veritas plane blades? It seems no matter how long I work, I never really bring up a burr. I can get them sharp, but never as unquestionably sharp as my chisels. Can anyone explain why this is so? I'm really curious.

I should tell you that my chisels are made by Blue Spruce, and are also A2. And that I use a Norton waterstone 1000/8000. According to Dave Jeske's website, his blades are tempered to 60 Rockwell, whereas the Veritas plane blades are 60-62. Is this the difference? Is it that the blades are just so much wider? I'm confused.

And, lastly, what system to you guys use to regrind your blades? I've looked at Tormeks, Baldor grinders, and bench top belt sanders. What is the best, easiest to use? Or can I forgo all of these very expensive options, and just use, say, a coarser ceramic stone? I've heard that they are very fast. How often would I need to regrind, after all? Once, twice a year???

Thanks for your help,

David

[David Weaver]

* It might be the width that's causing you trouble - or just a bigger bevel - narrower is always easier to raise a wire edge, and easier to flatten
* The A2 used in both should be similar quality, one might be harder than the other. I have noticed some variation in A2 irons, but it is within brands and not brand by brand (and has more to do with how an iron will release chips and leave lines, I don't generally use A2 in chisels)
* a cheap chinese grinder with a two-piece rest is fine if you are willing to invest a little time in making some setup blocks and spend $10-$15 on something to dress the coarse wheel that comes with it. I would not give up a grinder for a coarse stone. Buy it somewhere that will take returns in case there is something you don't like about the first one ,and exchange until you get a decent one. I used a ryobi dry grinder that had aluminum 2 piece rests for a while, they had finger tighteners - it was actually a reasonably handy little grinder. I don't think, though, that the current version has anything other than junky stamped one-piece rests. It takes little time to come up with the skill to use a stock two-piece rest rather than fooling with an expensive aftermarket rest. If the surface isn't big enough, you can always epoxy a piece of scrap steel to the two-piece rest.

I replaced my ryobi with a baldor grinder, but still had to get wheel balancers to get it as smooth as I expected. I think unless you want to support a US business (which is what I wanted to do in buying from baldor), you don't need to spend that kind of money from the standpoint of getting results - balanced wheels and a straight arbor don't require a US made grinder.

If you use planes and chisels fairly often, you will regrind much more often than a few times a year.

Everyone has an opinion about what's best and easiest to use. I have the tormek, a belt grinder, a dry grinder, a couple of coarse stones and a tabletop belt sander that I will use to coarse grind cambered irons. I could get by with any of them just fine, but I like the dry grinder the best.

[Mike Henderson]

David answered most of your questions. I'll add just a couple of things. I use a dry grinder - a Worksharp 3000 - to establish the bevel on chisels and plane irons. But almost any grinder will do. Then I use my water stones to put a secondary bevel, the angle depending on the use. I regrind when the secondary bevel gets too wide. When it gets too wide, it takes longer to sharpen the tool because you're working on a lot of metal. I don't have any rule on how big the secondary bevel has to be - it more depends on how much time I have. I tend to set aside some time and go through all my tools at the same time, selecting those with wide secondary bevels to regrind the primary bevel.

Mike

[Albert T. Tappman]

I've noticed the same thing with the iron in my Veritas #4 plane. I can't seem to raise a burr or get it sharp. I also have a Veritas low-angle block plane, and a LN #5, and don't have any problems getting those irons sharp using the same techniques. I've used a Worksharp 3000 and the same 1000/8000 Norton waterstone you have. I get chisels and other plane irons sharp, but have a problem only with the Veritas #4 plane iron. When I got the plane I put a secondary bevel on it with my Worksharp. It lost the edge with light use. I then reground the primary bevel on my Worksharp, put a secondary bevel on it with my waterstone, and honed a 10 degree back bevel with the 8000 grit stone. It still doesn't seem to be as sharp as my other plane irons and my chisels. I find the Veritas #4 frustrating to use. Besides the dull iron, there's too much backlash in the adjuster, and I have difficulty setting the blade depth. On the other hand, I'm happy with the Veritas block plane.

I gave up. I'll either try a Hock iron and chipbreaker, or just buy a LN #4.

[David Weaver]

What waterstone are you using?

Maybe there's a difference in carbides in the steels, which approach the hardness of the abrasive in common aluminum oxide stones. I've never noticed an issue with the veritas irons vs. anything else, but I am using a stone that will cut the carbides.

If you want to take the edge on the veritas irons over the top and your stones aren't up to it, sharpen them with the stones like you normally would and get the green chromium oxide stick (should be about 8 bucks or something) as a final step. Rub some on a piece of flat MDF that's about the size of a stone and use it like a stone. A little bit of oil (just a little) as a lubricant doesn't hurt. A sparing amount of the green stuff is plenty to do the trick.

[Gary Kman]

Hardest steel doesn't form a burr that I can see with a 10X loop. Neither my Record irons or Marples chisels. A burr is simply the steel bending over as it becomes thin. If it is hard, it continually breaks off. Grinding merely gets excess steel out of the way so you don't have so much to deal with sharpening. I bought a very friable white aluminum oxide wheel that I like. It wears quickly exposing fresh sharp edges and produces very little friction heat. Quickly is relative, they last me for years.

When I get to my waterstones I can't consistently get a good edge without a guide holding the tool at a precise angle.

[Fred Krow]

The composition of A2 is relatively standard however, the heat treatment can vary widely.

Some are Cryo tempered and others not. The temperature control in the furnace is also critical with the newer air hardening steels.

As mentioned earlier the type of stone used may affect raising a burr and ultimate sharpness.

Regards,
FK

[Russell Sansom]

1) My use of A-2 is a bit limited, but there occasions where it takes FOREVER to get the regrind I want on certain chisels. 4-10 times longer than the finest high carbon that are some of my daily users.

2) I use a Tormek because I grind to take off the absolute minimum steel with each regrind. A very shallow hollow makes for self-registering hand sharpening until a regrind is necessary. Usually, I can get 3 to 5 re-honings before the hollow is used up. Generally, I put on a secondary bevel a few times, then regrind.

3) As a relatively new sharpener you might appreciate the precision and the simplicity of the Tormek. Dry grinders have two problems for me ( that's "for ME." you might be different) overheating and hand-held-ed-ness. For example, it's pretty difficult to grind a skew chisel without tempering the delicate point.

I've gone through a couple sharpening styles in the last 50 years, ( oilstones then waterstones ), and this is almost the golden age of sharpening right here. There are internet movies and a tons of advice. Water stones like the Shaptons make things even easier. You can buy a 4" thick granite plate for $45, for goodness sake!

I find that the more assertive people tend to berate precise, careful sharpening (Heh...are you trying to produce chisel to go into a museum! What!!! Do you want to sharpen or work wood?). I find it comforting that my irons are not far off perfect even when they need a serious regrind. They subsequently require the least amount of time and steel removal to put them back in order.

The thing is to find sharp for yourself without taking too much stock in everybody else's closely-held beliefs. Once you understand how to get it, you can easily move from one method to another and assess what you do and don't like about it. It can be price, messiness, slow-ness, low-risk, consistency...etc.

[James Scheffler]

I'm having a similar issue with my latest Lee Valley A2 blade, which is one of the 2" Stanley replacement blades. I've tried going through the same sharpening sequence as all my plane blades, but it's just not getting that sharp. (I start with a Norton 1000/4000 stone, go through wet/dry sandpaper grits 1500 - 2500, and end with a leather strop with chromium oxide compound). This works great for the first three LV A2 blades I bought, but not so much with the latest one. I want to try again before I conclude that the heat treating was different on this one, but that's one theory I'm thinking about.

Jim

[David Weaver]

I would bet it's the size of the carbides (but I wouldn't bet much because I'm not a metallurgist). I thought this sounded interesting, because I use a LV iron and I get it sharp, but I'm sharpening with shaptons, and or a powered bit of leather using green stuff from LV.

So I looked up the effect of the cryo treatment, because the old LV irons were the one aftermarket iron that didn't receive cryo treatment (I don't know if that's still the case, hock, LN, and and now the IBCs have cryo written somewhere. Even shepherd said they cryo treated their irons, but the one I have still isn't very good so far anyway) to find it if cryo treatment made the carbides smaller. Maybe ron hock's book says something about this, I don't have his book.

Anyway, what all of the bits and pieces said was that cryo treatment did three things:
* stabilized the carbides that are already in the piece, stress relieving
* forming precipitates of carbides (much smaller than the original carbides) in the metal matrix that toughen the steel more (and in our case, presumably add additional wear resistance - most plain steel irons are tough enough for planing without carbides if they are properly hardened)
* stress relief of the material as a whole

None of those things sound like they would change the initial thing that keeps most people from getting an A2 iron sharp - the inability to effectively cut the big hard carbides

Maybe the carbides are bigger in the LV irons to begin with because of either the material or a difference in the heat treating process. I haven't noticed. I get the sense that the cryo treatment is more important for milling cutters where the carbide content (and the variety of the carbides present in quantity)is much higher than it is in a woodworking iron.

[Larry Frank]

I would easily take the bet on the carbides. I doubt if the size is an issue.

Heat treating A2 is fairly complicated. Careful temperature control is required with austenitizing, quenching, tempering and cyro treatment. Different sizes and thickenss have be be handled appropriately to get the same properties. I would call who ever you got the blade from and talk with them about your problem and see if they have some suggestions.


The cryo treatment is to complete the transformation from austenite to martensite. In tools steels such as A2, not all of the austenite will transform during the quench and the cryo treatment will complete the transformation to martensite.


(Yes, I am a metallurgist.)

[Terry Beadle]

I recommend you use diamond as an abrasive for all cryo A2 steels until you get to the final grit ( 8000 ~ 12000 ). The diamond will deal with the toughness that is added to the steel molecular structure. My experience is that I definitely get a small burr with diamond. I've used this on a Shepard tools thumb plane blade with good results. The LN blade has similar results.

There's just something about diamond being the hardest media that gets the shape of the cutting edge down to the brass tacks and the final honing on a good quality polishing stone puts the shine to it. IMO I don't think YMMV.

Good luck and keep us posted.

[James Scheffler]

I'm having a similar issue with my latest Lee Valley A2 blade, which is one of the 2" Stanley replacement blades. I've tried going through the same sharpening sequence as all my plane blades, but it's just not getting that sharp. (I start with a Norton 1000/4000 stone, go through wet/dry sandpaper grits 1500 - 2500, and end with a leather strop with chromium oxide compound). This works great for the first three LV A2 blades I bought, but not so much with the latest one. I want to try again before I conclude that the heat treating was different on this one, but that's one theory I'm thinking about.
Jim

Just an update. I resharpened the A2 blade today. After spending an extra long time with the higher sandpaper grits, it got to a comparable level of sharpness as a Hock O1 blade that I had lying around. It just took longer (as expected).

I wanted to do a comparison between the new LV blade and one of my other LV A2 blades, but as luck would have it they didn't need to be sharpened today. I think the new one is harder than the older ones, but I can't be sure until I do both at the same time. I'm curious about the edge retention on the new one. I've hardly used it yet.

Jim

[Chris Fournier]

A2 is a recipe for tool steel. Does your grandma cook like my grandma? No. There are variances from mfgr to mfgr and from batch to batch.

[Don Dorn]

A2 is a recipe for tool steel. Does your grandma cook like my grandma? No. There are variances from mfgr to mfgr and from batch to batch.

Thanks for making that so understanable - and with one short sentence. I could have read an entire article and not taken that away.

[Larry Frank]

Steelmaking today is not like how your grandma cooks unless she has a computer to calculate the additions, automated equipment to weigh out additions and complete logging of all the events used in making the steel. The control of the chemical analysis is very tight and the additions are more exact.

I certainly do not make steel like grandma cooks and you should be glad because I have been involved in making steel for critical automotive applications like axles, springs and gears.

Are there some differences from batch to batch - of course. However, the effect on the properties due to the chemical variations is small. I would tend to think that the variation in heat treatment is probably a bigger part of any variation in the physical properties.

[Jim Falsetti]

Jim,

Just another data point confirming your experience. I recently acquired two rusted Stanley bench planes, a #3 and a #5. As part of the rehab, I bought a LV A2 blade for the #3, and a Hock A2 for the #5. Flattening the back and sharpening the LV A2 took significantly more time, and required more effort, than the Hock A2.

Jim