Ashley Isles Chisels
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21 April 2018 at 7:59 pm #530771
I am not sure what the difference is between mkI and mkII, but I have a set of AI bench chisels I have been using for many years with a wooden mallet. The bubinga handles are not a problem.
Dan
@etmo I found more reasons to hate A2 for chisels : – ). Ron Hock, in a discussion of O1 vs A2, explains that while the A2 is more durable against what I’ll call shaving wear, it is more likely to crumble. So, for chopping, you need a steeper bevel angle, maybe 35 degrees rather than the 30 you’d need for O1. The finer structure of O1 leads to a sharper edge even though it requires more frequent sharpening.
The higher bevel angle is consistent with what I’ve seen. Even hand pressure paring cross-grain in oak to tune the shoulder of a tenon led to edge failure in my LN until I really steepened up the bevel to around 35 degrees. In the same wood, my Narex were happy around 30, maybe even a touch below 30. I thought it was just me, but Hock’s note confirms this. Note that a steeper bevel means more tendency to compress and jump back into a knife line, so this isn’t what you want in a chopping chisel. You can use attentiveness and care to protect your line, of course.
The bulk of my chisel work is chopping and digging, whether for dovetails, housings, mortises, or shoulders. I may try to sell these things.
@ed — we can agree that any metal which requires both a different angle and attentiveness should be banned 🙂
It’s often said that O1 “can” get sharper, for example, Ron Hock’s summary of the differences between the two steels, but as with many things, the devil is in the details.
You know tool steels contain carbon, about 0.5% up to over 2%. The minimum level of about 0.5% is required to allow the steels to harden to a decent level, say 60 HRC level during heat treating. The excess carbon above 0.5% plays little role in the hardening of the steels, rather it is intended to combine with other elements in the steel to form hard particles called carbides. Tool steels like A2 contain elements such as chromium, molybdenum, tungsten, and vanadium to combine with the excess carbon to form chromium carbides, tungsten carbides, vanadium carbides, etc. These carbide particles constitute from less than 5% to over 20% of the total volume of the microstructure of the steel. The actual hardness of individual carbide particles depends on their chemical composition — chromium carbides are about 65/70 HRC, molybdenum and tungsten carbides are about 75 HRC, and vanadium carbides are 80/85 HRC.
Who cares about carbides? Well, people with concerns about durability and sharpness. Why? Because carbides are like granite rocks in cement — they are the hardest thing making up the mix, and take the most wear. The downside is that like rocks in cement, carbides are also the largest individual thing in the mix, sometimes dozens of microns.
This, btw, is Lee Valley’s not-so-secret sauce with their PMV-11 steel. It’s just a more expensive mfring process whereby the steel is atomized into tiny droplets rather than cooling in a huge vat. Keeping the droplet size small allows super-rapid cooling which minimizes the carbide size, and they also probably use tungsten instead of simple chromium and Mo, so their carbides are harder than those in A2.
OK, so carbides are hard but big. How does A2 ever get sharp if it’s these huge chunks of 50 micron carbide? Well, as I mentioned above, only between ~ 5-20% of the A2 contains any carbides at all, and just that small percentage is what makes A2 so much more durable, difficult to sharpen, etc, etc. So 80-95% of your A2 chisel can get every bit as sharp as your O1, and, depending on the carbide size and distribution, maybe even more.
The steeper angle is because the carbides are easier to break out of the surrounding matrix due to their size — you can get leverage on them. So if they break out, they leave a hole, therefore not a perfect edge anymore. By fattening that angle you put more metal behind the large carbide particles at the edge, leaving more volume in which the big iceberg of the particle can be safely submerged, and reducing any leverage available against the particle.
Lastly, O1 has carbides, too. That manganese in Hock’s O1? Yup, manganese carbide. So O1 has these issues, too, just to a lesser extent because yikes, too much coffee again, I’ll cut this off here with apologies!
TL DR it’s not quite so cut-and-dry
@etmo no apologies needed. Interesting stuff. I need to find a skinny book with a name like “Metallurgy for Physicists,” or better yet, “Metallurgy for Physicists that don’t know diddly about materials or condensed matter.”
For chisels, I’m still of the opinions that for A2, just say no. That said, I’m glad you like them, because I can then ask, Wanna buy a nice set of LN’s?
Ed,
You’ve gotten a lot of great responses to your question.
This isn’t the first time the issue has come up and in an effort to get a more definitive answer, I posed the question to Ashely Iles directly thru their website.
This is their response:“Dear Mr Gates
Thank you for your email with my limited experience of wood working I would think cabinet making without a mallet would be impossible to do.
We impact test every blade we make. So after passing this test they will easily be able to tolerate moderate use with a mallet. My only concern would be over enthusiastic use when cutting a
deep mortise for example.All our tools are unconditionally guaranteed with out time limit so we will always replace any tool that fails in any way.
But remember that these tools have been forged and ground thin with fine bevels for cabinet makers use.
If you have any more question do not hesitate to contact me.
Yours Barry Iles
(Director Ashley Iles ltd)”
Hopefully this will provide a great measure of reassurance to those considering a purchase of Ashley Iles products.
Best,
Craig@craig Thank you for that. Before starting this topic, I contacted them and was told, “no mallet,” but I’ve suspected they were being cautious. Your reply was from Mr. Iles himself, so I put greater faith in it since I don’t know where in the company mine originated.
As it turns out, I purchased one 5/8″ to try and it arrived yesterday. I prepared it with a bevel just a hair steeper than 25 degrees and was able to take end grain shavings from soft construction pine. A little care was needed, but it cut beautifully. I then pared a tenon shoulder in oak without changing the bevel. Unlike any other chisel that I own, the edge did not fold or crumble with this somewhat low bevel angle. I then chopped a dovetail socket in some overly hard oak from Home Depot. I never felt a major failure of the edge, but when I took it back to the pine, it would not pare without tearing. There were a few very small nicks in the edge at this point that required me going back to the fine stone to remove. Had I steepened the bevel to 30-ish, as would be more reasonable for oak, I’m confident it would not even have had these little nicks.
Bottom line- This steel was more durable than that in any other chisel I’ve tried, far better than the LN A2 and better than the Narex at this angle. It was easy to grind and hone on my stones and easy get to a polished edge on the strop. Of course, this was just a small test, but I think I’ll order a set now. The blade is about 1/2″ shorter than the Narex, so they won’t have as far a reach for housings, but I’m not concerned. The handle is perfect for my hands and the balance is excellent.
Oh, as everyone promised, the ferrule was loose. I clomped it with a drift to make the ferrule slightly oval, and now it seems fine.
I received my set of 6 Ashley Iles bench chisels today and now see why they caution against a mallet. For 1/2″ and larger, the fine lands still leave a substantial blade, so those are likely fine to use with a mallet and reasonable care. The 1/8″ and 1/4″ are practically triangular in profile. Hitting the 1/8″ with a mallet would be insane. Hitting the 1/4″ might be asking for trouble.
The 3/8″ chisel is right in between. I can’t decide about that one. Is that a size some of you have malleted for either dovetails or mortises in oak or maple? If mortises are out, that’s fine. I’ll beat on the LN without regrets. I’d like to do dovetails in hardwoods, though.
Here is a photo: 1/8, 1/4, 3/8, 1/2, 3/4, and 1″.
Attachments:
You must be logged in to view attached files.Insane I may be, but I use my mallet (thorex 712 r, IIRC — same one as Paul) with my 1/8″ AI all the time. I’m not mortising oak framing timbers with that little guy; it works really well for tight-n-skinny “London-style” tails, where you don’t have enough room for the 1/4″.
I’m finishing up a jewelry box for the wife, and the 1/8 has been seen a ton of use on this project. All the tails on all the drawers, front and back, cleaning up the sliding dovetails for the carcass walls, cleaning up all the drawer bottom and drawer runner grooves, and all 10 dadoes for the drawer runners.
Certainly wouldn’t exert a lot of force through the mallet with the 1/8, but that rule holds true for any bench chisel — I’m more gentle with them than with a mortise chisel of the same size.
@Ed I have used the 3/8 and 1/4 for dovetailing drawer sides in maple. Not thick stock, less than 1/2″, and I tend to go fairly lightly. I don’t think that you’ll have a problem with the mallet. I use a Thorax 710R which has a slightly smaller and lighter head than than the 712R that @Etmo and PS use. The drawers in the back of this photo were done with the 3/8 for certain. I most likely used the 1/4 to split the waste.
If however you lever too big a bite on a mortice with the 1/4 you will feel it start to bend. I’d go back and take a smaller bite rather than force it.
Cheers,
PaulAttachments:
You must be logged in to view attached files.@etmo
Careful! I think that you will find that the Manganese in O1 is not there to form carbides – it is there for other reasons – mopping up the impurity Sulphur being but one important reason. Iron can make plenty of carbides itself with enough Carbon in the steel (typically over 0.9%)And the carbide particle size formed in powder metallurgy is only a very useful side effect of being able to produce alloys of metals which literally cannot physically be produced without superfast solidification rates (atomisation to form powders). Sintering of powders existed a long time before someone found a couple of oddball alloys that are useful for toolmaking by virtue of their fine carbide particle distributions.
I’m really happy that people are discussing the finer points of O1 steels against A2 steels for chisels. My LN chisels are in fact O1- purchased before he deleted them from his line of products to concentrate purely on A2. O1 is so much easier to use to make DIY small tools yourself as it is so easy to harden and temper. Same with silver steel rod. No cryogenics required!!
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