Sharpening, Steel or both.

[G S Haydon]

With what I've recently seen regarding sharpening, does it mean that modern steels are a waste of time?

Chisel tests

My hunch is you need to sharpen property, this is the key. And if Buck Bros chisels can outperform PMV11 then woodworkers can divert funds to wood, hardware etc.

 

[Bm101]

So it's a mini pig sticker.

 

[D_W]

Three things in order:
* optimal sharpening for speed and time
* hardness and geometry
* alloy

There are two things highly alloyed steels do well in wood:
1) they're more stable and easier to make a tool with less follow-up (and in the rare instance it's needed, things like matrix steels can go ultra high hardness and still be tough). Yxr7 is an example for japanese chisels (but they're not expensive in japan, only to us).
2) if you're looking to plane long distances of wood, then there's truth that the alloying can greatly increase the length planed.

But the first bullet point saves the most time in orders of magnitude, and deficiencies for the lower can teach good habits. Have an iron a touch soft? Learn how to plane and take more off each pass so that the thin passes (that rely on high hardness) are just a few. That's a gain all around, free.

When you start putting blades in ideal situations (in machinery, etc, where the orientation never changes, or industrial process), then 3 (combined with 2) comes into play.

 

[Jameshow]

D_W why does thinner shaving put greater strain in a blade? It seems counter intuitive?

Knots tend to be the real killer!

I think doing the majority of work and then sharpen or use a different plane for the final passes?

Cheers James

 

[D_W]

Thinner shaving doesn't put more strain on the blade, but takes greater sharpness to lift. It's a sharpness indicator while geometry is an indicator of resistance to damage.

Knots batter edges for sure - a pointed apex will always have problems. A buffed underside (like described on the woodcentral article) shortens edge life due to clearance loss, but something like 20%. If there's anything causing chipping, it greatly improves edge life - the difference between hypothetical and practical on the ground. That was a surprise.

Softer irons are brought to life by the buffer because no easily bent apex is left and the buffer finishes them easily while we deflect them a little sharpening and the abrasive bites deeply.

You can use two different planes, or my preference is just sharpen once there's edge damage. A half dull smoothing plane with a nice fine uniform edge still leaves a great surface. It's the notching and inability to stay in the cut that spoils the surface with lines (nicks) or little ripples (plane not starting cleanly or staying in a cut).

Heavier shavings don't seem to damage plane edges, and may in some cases help edges start well.

(there has always been guidance to eliminate notching - even odate's book talks about adding a steep back bevel for chippy irons or planing teak). But rounding the bevel works even more, provides a much brighter finish and much longer edge life (and there's nothing really to remove, the tiny buffed tip is removed with each secondary honing.

It just feels a little funny because when you buff the lower side of the apex a little bit, clearance is reduced. The plane feels like it will be dull soon, but the surface is bright and it planes on for a while.

Just another free option in your toolkit.

All that said, if you really want to gauge just how sharp something is and just how perfect the plane setup, keeping a nice planing test board of a medium hardwood will allow you to compare. Exotic levels of sharpness will make bonkers thin shavings, and there's no way to argue that a 2 thousandth shaving edge and a 3 ten thousandth shaving edge is the same. In practical woodworking, there's not much of either of those - usually the 2 thosuandth type just for a few passes maybe followed up by a couple of passes half that on the very worst of woods. the 3 ten thousandth type is just a confirmation that an edge is very uniform and defect free as it takes little to get a shaving like that to split or fail to lift.

 

[Cheshirechappie]

Graham, I'm rather inclined to the view that once you've practiced keeping tools sharp for long enough that it becomes a fairly quick activity you do without having to think much about it, you can touch up a tool that feels it's dulling whenever you want. Also, once you've worked with your tools long enough, you know what they like by way of bevel angle to keep a working edge for a reasonable time. Then, pretty well all edge tools (except the real junk) are good enough for most woodworking, and worrying about exactly what grade of steel it's made from becomes unnecessary. You can concentrate on building the skills of making things, not on 'sharpening sessions'. That said, it's necessary to spend some time practicing sharpening to become reasonably quick and confident at it - but that's no different to planing, sawing, marking-out, or any other woodworking skill. The more you do it, the better you get, generally.

The exception is those few people working very hard or abrasive woods regularly, and for them, perhaps there are some advantages to fancy steels. I think it was Karl Holtey, back in the late 1980s or early 1990s who first used A2, on the grounds that the planes he made were often used by people working tricky timbers, and he wanted to make planes even better performing than the vintage infills he'd studied quite extensively. Since then, various other steel grades have been tried, becoming fashionable for a while in some cases. The problem is that a tool steel that gives an edge that's noticably more abrasion resistant at work is also noticably more abrasion resistant when it needs sharpening, so you need not just fancier steels but fancier stones as well. Pays yer money, takes yer choice.

So, for me, invest some time in becoming quick and proficient with whatever sharpening regime you prefer, and the need for everlasting steels becomes (for most woodworking) far less pressing.

 

[D_W]

I'm sure the knife community was gaga about A2 at some point (that's long gone if it was true). I have a friend here who was slipping A2 irons to craftsmen at Williamsburg before they were ever available from Karl or others, but he was also interested in blade making (the coopers at williamsburg were using single iron planes with 1075 or something in it - single iron planes already have a shorter sharpening interval, and something like 1075 will have about 60% of the edge life of A2).

A2 is far easier to deal with commercially, though, which is probably the reason we see it. LN was using water hardening steel and could not get it quenched all the way to the slot without having warpage problems, so they didn't harden the entire distance below the slot for a lot of their earlier irons. My CW friend mentioned above suggested they switch to A2, and they sort of blew him off and later went to it. I'm sure he's not the only person who suggested it and at this point, they can't get heat treatment for O1, so A2 it is.

I have done a fair amount of testing of irons, and posted such here. I"ve also made irons out of (the list of what I've used for actual planing is probably 4 times as long as this):
1084
1095
52100
O1
AEB-L
XHP (likely PMV11)

AEB-L is the only one I have a little trouble with - it has the potential to be great, but there's not a lot of wiggle room with it when it comes to heat treatment (unlike XHP and O1, which both turn out to be pretty forgiving and consistent). AEB-L could be thought of as a finer grained steel than V11 with slightly greater toughness, a little less wear resistance, but still approaching 30%-40% more than A-2 (even in irons that I've made that aren't optimized are running around 65% more footage before dullness vs. high hardness O1).

But does any of it matter? Probably not. The draw for AEB-L in the group above is that it can be sharpened on oilstones, it's stainless and it has extremely fine grain - better than some steels that people consider very fine. No other stainless that I've seen comes close for grain fineness (it's far finer than A2, too).

what would I choose if I could only have one thing for all plane irons or chisels? 52100 or O1 - their performance is almost identical. The edge life increase with XHP/V11 is novel, but it doesn't show up in chisels (XHP's toughness isn't that great and abrasion resistance in chisels doesn't get you anywhere - but you still have to grind and hone longer with it - even on diamonds - anyone who's convinced themselves that it sharpens as fast as something like O1 is confusing sharpens finely to sharpens as fast - it grinds off slower).

Geometry, hardness and sharpening speed far far more important than any of the above. For tough woods, I like a soft iron that can be sharpened quickly on a buffer. Exactly the opposite of what I thought would be needed, but if I took a soft iron in truly tough wood, addressed the geometry with rounding, and someone else bought some kind of exotic high carbide high hardness iron and sharpened with a guide, I can better them any time over and over by manipulating geometry rather than switching steels.

 

[Jacob]

So rounded bevels OK then!
I've never claimed that a rounded bevel directly improves planing performance, but it does facilitate sharpening as it's faster and easier to be free handing away, not too carefully, rounding bevels unintentionally, as you gaze out of the window.
This in turn indirectly helps with planing as sharpening gets done more often, being less of a chore.
Conversely the sheer tedium of modern sharpening makes "edge retention" more valuable - it helps alleviate the problem of having to repeat the process of sharpening with jigs, flattening stones, etc etc

 

[D_W]

no, not just a rounded bevel

If you try to round over a whole bevel ala sellers, it'll still chip. The modification at the edge is much more drastic, and then no rounding behind it (the angle behind it is shallow).

The trouble with the idea that the bevel makes strength is that it creates fatness where it's not needed, and it doesn't address where the failure actually occurs.

Confirmation bias and no actual examination causes people to come up with all kinds of goofy ideas (such as the idea that the convex bevel makes for a stronger edge - it makes no difference).

The geometric modification is more drastic and occurring over a couple of thousandths. It's sort of a difference between "common sense" and observation.

There's a good saying that I heard from a guy busting knife myths. You propose an outcome, then you test it and observe. If what you observe differs from what you expect, then the next time you run the experiment, what you expect should be what you have observed.

To fail to recognize the value of actual observations is a trap. If they're unexpected, you can explain them, and maybe even explain when they're not valid, but if observations don't match your expectations and you can't explain why, then your observations are you expectation in the future.

Here's another example:
* I planed about 50k feet of wood to test iron durability in the last couple of years. I rarely do this stuff anymore unless I think someone else will do a rubbish test and it will provide false conclusions (like the FWW style reviews of chisels deciding what's good by smashing a chisel an inch deep into a piece of wood - we don't work that way).

* When I did this testing, it's clear that V11 lasts about twice as long as *good* O1 in clean wood

* When I plane something other than clear smoothing, I don't see the same benefit. I do "actual work" most of the time and never perceived this 2-1 interval occurring, but planed 3 separate tests with V11 vs. various irons and the intervals remained the same in all 3 within literally a couple of percent (e.g., observation one may have been 101%, 2 would've been 98% - there wasn't much there to suspect more trials would change things).

* going back to regular work, I made a gaggle of XHP irons (they also tested about the same against O1). But when I went back to work, I didn't find them as nice to use in anything other than clear smoothing.

So, my first supposition was that V11 was marginally better than O1 in a durability test (there were other surprising observations - it does have less resistance through the wood and leave a brighter surface off of the same sharpening stone). It turned out to be 2 to 1 in long grain. Going back to working with it in heavy work seems to prove that OK, the first test is true. But in the cycle of actual work, I don't perceive the same benefit, because things come into play (like knots, silica, dirt). Those types of issues change the outcome because they're not involved in a standardized test.

I ran into a lot of resistance to the idea that XHP lasts twice as long in clean wood (especially if someone doesn't like Lee Valley), but knife folks have recently run (probably before I did my test) abrasion tests through a standardized machine and found the same thing - it's relatively long wearing, but the flip side is that it's not that tough.

if you don't care about chips in irons, then it doesn't matter - it lasts a long time, longer than "normal" irons. I hate chipping - at some point, it slows down dimensioning.

I have pictures of edges that will resist silica chipping, but people usually have irrational reactions like "you can't do things in thousandths".

We do things in thousandths all the time and have discretion to know where they matter and where they don't - we just don't ever measure them.

 

[D_W]

(I hassled LN customer service to try AEB-L, too - I'd like to put my flag in the end of the field to point to later if it shows up in their planes!!)

I doubt they'll listen to me, as that's only half of the problem. The other half is getting someone who will actually harden and temper it properly as it's cheaper than A2, but the hardening and tempering will be more demanding.

It also benefits from cryo treatment, but not for the same reason as A-2 - A2 has a problem with large grain and dispersed carbide whereas AEB-L has tiny grains and no such problem, but AEB-L has less carbon and the nitrogen/freezer treatment converts more austenite to martensite (translate, the change from really hot to suddenly cold that makes steel hard is done better if the final temperature isn't just open air, but much lower - the process goes further, thus the steel ends up harder).

The last kicker - AEB-L is extremely cheap, especially for a stainless, as it's in widespread use in your razor blades (or something like it is). It's half the cost of precision ground O1, or about $7 for enough to make a slightly thicker stanley iron. The step up in cost for a shade tree maker like me to get everything out of it, though (get it hard and fine and not chippy at all) is about $1800 for a small temperature cycling furnace though. Out of the question if it's not for profit.

 

[D_W]

Statement above shouldn't be missed, though - alloy is the very last consideration after everything else is handled, and by the time the other items are handled, alloy becomes insignificant. Fast sharpening, geometry, and then maybe speculating on hardness (finding irons in a hardness range that you prefer).

 

[Jacob]

no, not just a rounded bevel

If you try to round over a whole bevel ala sellers, it'll still chip. The modification at the edge is much more drastic, and then no rounding behind it (the angle behind it is shallow).
......

That just doesn't make any sense at all. How could rounding of the "primary" bevel have any effect on the strength of the secondary bevel (assuming I've got my modern sharpening jargon right! ).
Nobody, not even Sellers, tries to "round over a whole bevel" what would be the point of that? You've totally misunderstood the basic freehand process.
They may end up rounded over completely but only after a lot of sharpenings - it's a by product with no bearing on the sharpness of the edge. In any case many would take off the back of the bevel (a.k.a. "grinding a primary bevel") to speed up honing at the edge, so it would only be rounded towards the edge, could be flat or hollow ground further back.
Glad I'm not struggling with modern sharpening hysteria any longer!

 

[D_W]

jacob, you don't know what you're talking about. You care about what makes sense to you, not results.

There's a myth that flat bevels are stronger, or that convex bevels are stronger. They may be on crow bars.

The tip of a chisel has to be very steep to avoid chipping - much steeper than 30 degrees. Just back from that needs to be much shallower. It can be 30 degrees or 30 degrees convex if you want, but it's wasted energy in everything the bevel comes in contact with.

Period.

This isn't modern sharpening hysteria, it's doing something better than what you're doing - less effort, more edge life, sharper. Better all the way around.

You don't have to do it, but your dismissive attitude is annoying because you can't do fine work so needing to ramp things up to do fine work makes no difference to you.

There's also a ramp up in edge life for refinement. It's on the order of +50% longevity between starting with something like a fine india stone vs. addressing the tip with an ultra fine abrasive. These things elude you because they're not part of cutting test joints in salvage wood.

They may not elude other people in terms of usefulness.

The "hysteria" that I've implemented at low cost has gotten positive response instead from actual period woodworkers here in the states - people I don't know. I'm looking to find useful things for me. Those things will be useful for them. If someone is making fence posts, I've got nothing for that.

 

[D_W]

Interestingly, I was reading a forum that I don't post on yesterday, comparisons of expensive chisels vs. less expensive chisels. One of the very avid makers on the woodcentral forum jumped on board with this stuff when he tried the method in the video above and it salvaged narex chisels for work in hardwoods (the narex chisels aren't spectacular at edge holding until you get to their normally quenched and tempered tools - the others are austempered and not quite hard enough to have good edge strength, but the austempering process makes them inexpensive).

A tiny amount of edge modification (a very tiny amount) makes them stand up fine.

I saw someone (I don't know who it is) mention yesterday that they "unicorned" two of the lower cost narex chisels to get the edge failure under control.

What's interesting is that I proposed a method, described it, people use it and get results. I don't have to say that nobody allowed me to do this or that or it will be site work related, I just have to show it, someone else does it, they get results. It's better than free - it saved them money.

 

[JohnPW]

Is there any difference when sharpening chisels for hand pushed paring and plane irons?

And also how would Veritas 01 and PMV11 block plane irons compare for planing ebony? Would PMV11 stay sharp longer? It's not for surface finishing, it's going to be sanded, the iron only needs to be sharp enough for a clean cut.

 

[baldkev]

D_w, have you studied the edges with a microscope? Im definitely not a sharpening guru ( my site tools get a quick going over on a 1k diamond plate ) a couple of years back i learnt shaving with a straight razor. Part of that is stropping and honing the edge to keep it razor sharp. A lot of the razor guys actually check their edges with microscopes.
I got a couple of good stones and also some lapping film and diamond pastes, my first attempt was rubbish, a new ( cheap ) razor, turned up blunt. I tried and failed to get a razor edge. My second attemp was on an Ern Ator and that with the lapping film and good instruction ( youtube ) got me my first razors edge!!! I was so chuffed with myself!

 

[D_W]

planing ebony of any kind, I'd sharpen a block plane iron and a paring chisel similar, figuring you want the total bevel on a block plane for ebony to land around 60 degrees or so (bed plus bevel) if you're planing a surface. If you're planing to remove stock, then you can tolerate a little tearout (esp. on ebony since it doesn't really have any "straws" orientation and when it tears, it just sort of crumbles at the surface).

Veritas tempers O1 far softer than V11. I'd have no preference on ebony if you sharpen and modify the tip of the iron with a buffer. If you sharpen to a pointed apex, then probably the V11.

If you avoid chipping, LV's V11 will probably stay sharp more than twice as long as their O1. It would be nice if they offered both at the same temper (hardness), but they seem to position the O1 as soft for people who want it to be really easy to sharpen.

I sharpen all chisels except mortise chisels with a shallow final bevel (about 25 degree final bevel) and then buff over the tip. It'll stay sharp nearly forever.

If you want to do this trick to the bevel up iron, then it effectively controls tearout around +5 degrees (as in, if you want to buff the tip of an iron so that it will hold up and stay crisp in a bevel up plane, 55 degree apex total plus buff will behave just like 60 degrees, but it will feel sharper and the shavings will look different, like they're waxed.

How you get to the 55 degree is just final bevel plus bed.

The answer isn't quite as simple for bevel down planes as people seem to have some trouble managing clearance on bevel down planes buffing the bevel side, but I do those (when warranted) with a final bevel around 23 degrees, then buff. It sounds very shallow, but the buffing rounds the very tip over abruptly like this:

http://www.woodcentral.com/articles/images/958b.jpg

and damage doesn't occur to the edge. too much buffing and clearance is lost. I never had much of an issue with it, like I said, but it's puzzled a lot of people getting the touch right.

http://www.woodcentral.com/articles/images/958m.jpg

Note in the same piece of wood with the same iron how much better the buffed iron (buffing over a 23 degree final angle) held up than the 32 degree flat bevel - the apex got battered by silica on the latter - the former ignored it.

 

[D_W]

D_w, have you studied the edges with a microscope? Im definitely not a sharpening guru ( my site tools get a quick going over on a 1k diamond plate ) a couple of years back i learnt shaving with a straight razor. Part of that is stropping and honing the edge to keep it razor sharp. A lot of the razor guys actually check their edges with microscopes.
I got a couple of good stones and also some lapping film and diamond pastes, my first attempt was rubbish, a new ( cheap ) razor, turned up blunt. I tried and failed to get a razor edge. My second attemp was on an Ern Ator and that with the lapping film and good instruction ( youtube ) got me my first razors edge!!! I was so chuffed with myself!

Yes on the microscope. the images above are mine - I sold natural stones for razors for a little while and got a metallurgical scope as I thought it was the only ethical way to grade them (Too much woo in japanese natural stones - the microscope sorts out the posers in a hurry). I used a cheaper microscope earlier on to sort out sharpening straight razors for myself - it's funny how a woodworker will go to them and think you can just sharpen them with a plane blade and the edge "ain't having it" at 16-18 degrees - it has to be sharpened first and then "sharpened lightly" for a while to really get the apex crisp, and then the apex has to be stropped or it'll dent easily when shaving or deflect.

I have an article on wood central that shows some of the comparative edges with flat bevels and rounded bevels

Searching For Unicorns In A Field Of Abrasives And Wood

And ran some standardized durability tests for plane irons (it's really only fair if you ensure that all of them are sharpened to the same level at the start as mediocre sharpness only puts edge life around 2/3rds of totally sharpened edges. Those are incidental things learned, not something I was looking to prove.

 

[baldkev]

Im going to have to read the unicorn link tomorrow, im a bit bushed for one day! I found it amazing just how much small things affected an edge. I touched up a razor on the lapping film, then ran it over a balsa strop with diamond paste, but i must have done something wrong because it was sharper straight off the lapping film ( arm hair test )

 

[D_W]

John, my suggestions above are if you really want to plane something well and eliminate failure (and end up sharpening a lot less). Nothing is obligatory, but it's possible to sharpen less and have more predictable results.