Chisels and edge chipping

[Christopher Juncosa]

TL;DR: I bought what I thought to be a nice chisel but it doesnt hold an edge well and the edge chips very easily. Should I take it back and try another brand, or is this the life of a chisel?

So I have three garbage chisels, Stanleys, plastic handles, probably $9 for the three of them. They work great however, and I sharpen them regularly and they perform admirably for 99.9% of my work. I needed to pare out lots of troughs on white oak and none of the chisels were narrow enough so I excitedly went to get a new tool to do the job. Unfortunately I wanted to get working so my option in nice tools in a B&M is my local woodcraft. They had a couple chisel options but not many really: Stanley SH, Marples Blue handles, Pfeil, Standard Woodriver bench chisels, and new fancy Woodriver socket bench chisels. I liked the octagonal handle of the Pfeil and feel in hand, plus the sales guy was raving about it, so I went with the Pfeil.

In use however, I have to say Im really disappointed. I set it up before use, back was super flat, sharpened and took a super fine edge. But man, just went dull on me real quick after any paring work. And Im talking like not even the equivalent of one dovetail. OK fine, resharpen - great edge, keep working - same thing. Granted its end-grain paring of white oak, so a little slack for it there, but my junky Stanleys were outperforming it on the larger sections they could fit into. The final kicker was any chopping I had to do, or aggressive paring, ended up chipping the edge. Not huge gouges, but the end looks like its serrated and has little micro-teeth. Any prolonged use after the initial sharpness wore off would create the chipping.

So the questions are ... is this normal? Is this the life of a premium chisel? This one is 8mm (5/16-ish) so its not huge. I have a 90 day return window so it can go back, and it probably will. I was hoping to really like it and grab a few more. Is it a bad example of an otherwise nice chisel/product? Give Pfeil another shot? I have half a mind to order the LN 3/8" socket (what seems to be the consensus favorite) and limp along till it gets here and just keep rolling with that product.

What do you guys think?

[Brian Holcombe]

Raise the bevel angle.

[Warren Mickley]

There are a lot of variables here, but I suspect there is nothing wrong with the chisel. There are a few things you could do to investigate: sharpen the chisel and try it on other species to get a feel for it, try your old chisels on the present white oak., etc.

Here in Pennsylvania we have about six oak species that are lumped together in the lumber trade as "white oak". There is a large range of hardness and texture among species and within individual species depending on environmental conditions. Some "white oak" is much harder than the hardness listed on charts and someone trying to duplicate your efforts might not have similar material. We look over a board pretty good before choosing carving material.

I would avoid hitting the chisel with excessive force (even though the wood is hard) and avoid harsh abrasives like diamond or Shapton, etc. I looked at the LN chisels at their hand tool event with a hand lens; every single one was chipped. Beginners are hard on chisels.

[Christopher Juncosa]

Interesting, 2 votes for 'theres nothing wrong with the chisels', which is encouraging. The primary bevel on the chisel is 25°, so I can increase that to 30 and see where that gets me. More work than Id like to do 'out the gate', but Im OK with it I suppose.

Truly Im not beating on this chisel at all, so the root of this question really is a sanity check for me. Ive even routed a lot of waste out to lessen the burden on the tool. Given the task its really 95% hand-force paring to clean out an area. I do think the W.oak is taking its toll on the tool, so Im hopeful thats really the issue. Even after its less than effective on the oak it still is adequately sharp to pare end grain walnut (all I have laying around ATM).

Ive read that sometimes the new-edge from the factory can be softer than the metal in the meat of the tool and a couple grindings/sharpenings expose the real quality of the tool, is that legit or just shop-talk?

[James Pallas]

I have many Pfeil carving chisels but only 1 bench chisel. It is the older style handle I've had it about 5 years. It is my go to chisel when the size is right. It has chopped in WO, hickory, and everything else that hits the bench. I have never had a chipping problem with the Pfeil tools and I chop with gouges also. The chisels is at 25 degrees and has never been changed. It has never been hollow ground just been to my smooth flat river rock once in a while. If I could justify the expense I would have more of them. I have to wear out others to do so. Maybe just a bad one or just needs a few more sharpenings to get down to the good stuff.
Jim

[Jeff Ranck]

Don't forget, if it is a new chisel that sometimes the new edge can have steel that is a bit soft or a bit too hard or otherwise problematic from the heat treating/manufacturing process. If the chisel is new, try grinding the tip back a bit and regarding the bevel to remove the original edge steel and see if there is "good" steel that won't chip behind it.

[David Eisenhauer]

It is very quick and easy to add in a 30/35 deg micro bevel to the end of your existing 25 deg bevel. Chopping into harder material can dull and/or roll the tip over. Try it and see what happens.

[Hasin Haroon]

Hi Christopher

As mentioned by a few folks here, raising the bevel angle will make it hold an edge longer, BUT - if you're planning on using it as a paring chisel I would hold off on increasing the bevel angle. Sometimes new steel just needs a few sharpenings to expose the good stuff. Try that for a while, and if it doesn't work, try a steeper angle.

[Graham Haydon]

Hi Christopher, just try honing at the normal 30 degree angle. 25 degrees is much to shallow for anything more than cutting with hand pressure of the lightest of taps.

[Brian Holcombe]

There are a lot of variables here, but I suspect there is nothing wrong with the chisel. There are a few things you could do to investigate: sharpen the chisel and try it on other species to get a feel for it, try your old chisels on the present white oak., etc.

Here in Pennsylvania we have about six oak species that are lumped together in the lumber trade as "white oak". There is a large range of hardness and texture among species and within individual species depending on environmental conditions. Some "white oak" is much harder than the hardness listed on charts and someone trying to duplicate your efforts might not have similar material. We look over a board pretty good before choosing carving material.

I would avoid hitting the chisel with excessive force (even though the wood is hard) and avoid harsh abrasives like diamond or Shapton, etc. I looked at the LN chisels at their hand tool event with a hand lens; every single one was chipped. Beginners are hard on chisels.

That's been my experience as well, some white oak I have received is simply brutal to work with and some of it is quite nice. There is a variety sold locally that presents as quite dark in color (by comparison to other white oak) and that stuff is truly hell. I am resharpening very often when planing it. The white oak that I'm more fond of planes about as well as white ash or red oak.

[Terry Beadle]

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[Terry Beadle]

You mentioned you wanted to make a 30 degree micro bevel on the 25 degree base.
Good! Try it and if happy, smile.
If not, then increase the micro bevel to 35 degrees. Don't be afraid to do this as I have some Ashley Isles chisels
that had to go through this increase until they were happy. The steel is excellent but requires the cut bevel to
be adjusted for the material to be cut.

The AI chisels have been using the 35 degree setting for over 3 years with only quick honing and have been
used on red oak, mahogany, pine etc. No chips, no rolled edges and a satisfactory smile with each use ... ;-)

Don't be shy...go high!

I also recommend setting up a spare chisel with a 17 degree bevel that you would only use on those stubborn
dovetail end grain cuts that crush the fibers instead of cutting. Hone it well and you'll be surprised on how clean
SYP ( Southern Yellow Pine ) is cut clean. Try it.

[maximillian arango]

avoid harsh abrasives like diamond or Shapton, etc.

Any particular reason to avoid them? I have Shapton stones and never heard any reasons to avoid them.

[Patrick Chase]

Any particular reason to avoid them? I have Shapton stones and never heard any reasons to avoid them.

Warren alludes to a "religious war" within woodworking, between advocates of natural silicate stones and people who think that man-made abrasives are up to the job.

What is factually true is that SiO2 grains (the abrasive in most natural stones) are more rounded in shape than Aluminum Oxide (the abrasive in all Shaptons above #320 and most other synthetics). SiO2 consequently leaves more obtusely-angled or "rounded" striations in the tool. Both of these facts can be readily observed in SEM shots of the abrasives and the sharpened tool, respectively, so I don't think there can be any controversy about these points.

The controversy lies in the practical impact of that difference. In general natural-stone advocates argue that the sharper striations from artificial abrasive cause crack propagation and chipping. This is obviously dependent on the steel, and particularly its toughness. Toughness is actually measured by characterizing fracture propagation from exactly such a sharp-cornered notch (Charpy V-notch test in US, Izod in Europe) so it tells us exactly what we need to know.

One interesting note is that moving to a finer abrasive doesn't change the basic profile of the striations (unless/until the abrasive particle size is on the same order as the steel's grain size, but let's not go there right now). Inasmuch as fracture propagation is truly an issue, finer grits don't necessarily help. Of course there are other issues besides crack propagation to worry about. Sharper striations mean worse flatness of the resulting surface, so inasmuch as that impacts edge quality you do need to use finer grits with "sharp" abrasives than with more "rounded" ones.

My own take is that:

1. As suggested above, you do have to sharpen to a finer grit or abrasive particle size with "sharper" abrasives to get equivalent results at the wood. You can get an outstanding edge from a translucent Ark (equivalent grit of something like #4000 depending on how you measure) but you'd need to go to 12K with a Shapton to do the same. It's probably worth noting here that Shapton is a "known scofflaw" when it comes to grit ratings - their 12K stones are about as fine as Imanishi/Sigma/etc 8Ks. It's not a big deal, you just have to remember to go higher with their stones.

2. For Western tools tempered to typical hardness I don't think that fracture propagation from sharpening striations is a real issue. I say this based on both the Charpy V-notch scores for the relevant alloys and based on my own experience.

3. Though I don't have enough direct experience with them to have formed an opinion, laminated Japanese tools have very brittle (low toughness) edges and are therefore inherently susceptible to fracture propagation. HCS at Rc66 scores way down into the "brittle" range on Charpy, and low enough that I'm not confident saying whether abrasive harshness matters on that basis. I therefore don't discount the opinions of people like Brian, who believe that their Japanese tools last longer when polished on natural waterstones.

[Patrick Chase]

A question for somebody like Brian: Have you ever compared polishing on CrO to your JNats?

I ask because Chromium Oxide is a gentler abrasive than AlOx, so I suspect that 0.5 um CrO film or a pure CrO compound (read: Not the stuff that comes in a green bar) could get similar results.

[Brian Holcombe]

I haven’t tried it, but it seems like something interesting to try. Only thing however is that it may well have no effect on Japanese tools

[Stewie Simpson]

I ask because Chromium Oxide is a gentler abrasive than AlOx, so I suspect that 0.5 um CrO film or a pure CrO compound (read: Not the stuff that comes in a green bar) could get similar results.

I seem to recall a prior discussion that didn't end well.


I am loathe to mention the topic of Pure Chromium Oxide Paste as being superior to what's being offered in the wax stick base, but here goes.

http://i1009.photobucket.com/albums/af219/swagman001/pure%20chromium%20oxide%20paste/_DSC0202_zpsm5idgwfd.jpg (http://s1009.photobucket.com/user/swagman001/media/pure%20chromium%20oxide%20paste/_DSC0202_zpsm5idgwfd.jpg.html)

The following is the Leather Stropping Block loaded with the PCOP. A finger tip dipped into the paste was enough to coat the full top surface of the strop.



http://i1009.photobucket.com/albums/af219/swagman001/new%20stropping%20block/_DSC0211_zpsnnpftuwb.jpg (http://s1009.photobucket.com/user/swagman001/media/new%20stropping%20block/_DSC0211_zpsnnpftuwb.jpg.html)

And here is the Pure Chromium Oxide surface after stropping a bevel up Stanley Block Plane Iron.

http://i1009.photobucket.com/albums/af219/swagman001/new%20stropping%20block/_DSC0212_zps1wng0fyv.jpg (http://s1009.photobucket.com/user/swagman001/media/new%20stropping%20block/_DSC0212_zps1wng0fyv.jpg.html)

[Patrick Chase]

I haven’t tried it, but it seems like something interesting to try. Only thing however is that it may well have no effect on Japanese tools

Cr2O3 hardness is Mohs 8-8.5, in the same range as Al-Oxide. It's quite a bit harder than either SiO2 or a Japanese tool.

Like SiO2 it's an inherently slow abrasive, but it will have an effect.

[Patrick Chase]

I seem to recall a prior discussion that didn't end well.

Yeah, but that doesn't mean we can't get it right the second time.

IIRC where we got stuck in that previous conversation was on the ever-contentious topic of whether the green bars were useful at all. How about we just accept that the stuff works well for some people (George for example), and focus instead on how pure Cr-oxide compares to JNats for edge life in Japanese tools?

How do you like your Cr-oxide paste after having used it for a while? I use 0.5 um Cr-oxide lapping film sometimes, and while it's slower than AlOxide (and waaay slower than diamond) it seems to leave a nice finish.

[steven c newman]

Best part of why I like to buy vintage chisels.......the "bad steel" is long gone. About half of mine are pushing 90 years old.....

[Jim Koepke]

Best part of why I like to buy vintage chisels.......the "bad steel" is long gone. About half of mine are pushing 90 years old.....

If the various studies mean anything a couple of my mortise chisels are pushing 200 years. My scythe was made before 1860 and some of my Buck Brothers gouges were made before 1870. We should looks so good when we are that old.

jtk

[Patrick Chase]

Cr2O3 hardness is Mohs 8-8.5, in the same range as Al-Oxide. It's quite a bit harder than either SiO2 or a Japanese tool.

Like SiO2 it's an inherently slow abrasive, but it will have an effect.

Continuing my thought, IMO CrO2 is best used in a manner similar to how you use your JNat polishers: Do the bulk of the sharpening on something faster-cutting, and then finish on the gentle abrasive to "round off" the final set of striations. If you use it that way then cutting speed is almost irrelevant.