Quangsheng plane blades

[Silly_Billy]

I read on Chris Tribe’s website that his Quangsheng No. 5 plane blade was made of hardened steel, which takes longer to hone but holds an edge longer. Does anyone know if this is generally true for Quangsheng blades?

 

[Rorschach]

I would hope all plane blades were hardened steel!

 

[woodbrains]

Hello,

Quangsheng irons are made from T10 steel, which is a water hardening steel. They are nice irons and they sharpen to a very fine edge. In the scheme if things though, they are not some new fangled exotic alloy that is a real pain to sharpen to a good degree, nor do they go on forever planing abrasive material. I think they are excellent or the price, take a super sharp edge, but probably little different than, say a vintage laminated iron. Good replacements though, about the nicest for the money.


Mike.

 

[patrickjchase]

Quangsheng irons are made from T10 steel, which is a water hardening steel. They are nice irons and they sharpen to a very fine edge. In the scheme if things though, they are not some new fangled exotic alloy that is a real pain to sharpen to a good degree, nor do they go on forever planing abrasive material. I think they are excellent or the price, take a super sharp edge, but probably little different than, say a vintage laminated iron. Good replacements though, about the nicest for the money.

T10 is a Chinese designation for W1. As 'woodbrains' says it's a water-hardening high-Carbon steel, similar to what was used in many older irons.

FWIW the reason Western makers don't use W1 any more is because like all water-hardened steels it has more of a tendency to warp and crack during heat-treatment. O1 has fairly similar sharpening and wear properties but is oil-quenched, "non-shrinking", and therefore easier to heat treat. As a consequence it has pretty much replaced W1 among makers who want a "simple" high-carbon tool steel. On the plus side, W1 is the cheapest of all of the tool steels, which probably has something to do with QS' decision to use it.

I've never seen a cracked QS blade, so they either have good QA or they've figured out their process well enough to avoid that. The two I've owned both took a fair bit of work to flatten, though, which is exactly what I'd expect from W1.

 

[Orraloon]

I wont get into the tech side of it but the 2 qs blades I have are OK. I also have a couple of Mujingfang wooden planes and the blades in them are also good. So far I have not had a bad Chinese blade.
Regards
John

 

[patrickjchase]

I wont get into the tech side of it but the 2 qs blades I have are OK. I also have a couple of Mujingfang wooden planes and the blades in them are also good. So far I have not had a bad Chinese blade.

I've had good luck with Quangsheng ("WoodRiver" here in the States due to a distribution arrangement). As noted above both of the irons I've owned have been a bit warped, but the same is true of most of the old water-hardened Stanley etc irons in my possession. It comes with the territory, and IMO it's a very reasonable trade for an inexpensive iron that hones easily and takes a terrific edge. It doesn't resist wear as well as some modern steels, and it's more or less the opposite of what was described in the original post ("longer to hone but holds an edge longer"), but all in all they're good irons.

I'm not as sold on Mujingfang's HSS irons. If I had to describe them in a sentence I'd go with the old trope about D2: "Takes a crappy edge and holds it forever". I think that HSS with its coarse microstructure, large carbides, and terrific heat and wear resistance, is better suited to machine cutting applications than to hand tools. The only exception I would make is for some of the newer and finer-grained powdered-metal HSS variants like Hitachi HAP40, but that's not what Mujingfang uses.

I think that D_W was making basically the same point about HSS in the scraper plane thread when he remarked that his Mujingfang polishing plane tended to leave tracks on the wood. The reason it does that is because of micro-chipping of the edge from exposed carbides.

 

[D_W]

Yes, tiny lines.

I also have a set of their cheap (and cheaply made) HSS chisels, which are just tapered crosses of flat stock with a very short tang stuck in a who-knows-what-kind-of-wood handle, and they take and hold a super fine edge, as well as anything I've ever used. No clue what they are, but they sharpen easily on a decent suita (not so much on an ark stone) - I'm guessing some kind of T series HSS equivalent, but could be wrong. If they didn't hold up so well, I would guess they weren't HSS, but they don't seem the same as the plane irons.

The one good use of those muji plane irons is abusive use in a common pitch plane (they will plane plywood, glue, etc well) - they're cheap, but in any plane, they are not going to leave a finished surface that doesn't have marks.

(the thing that made that plane obnoxious to use, though, was the 63 degree bevel angle with no fine depth control - or maybe it was just the 63 degree angle. You can take a smoother shaving or you can take a smoother shaving. If you try to do anything else, you will be stopped in your tracks. Even if the iron had been carbon steel, it wouldn't have held up due to the scraping type of cut).

 

[matthewwh]

I think what Chris is driving at is that T10 optimises slightly harder than O1 (it can be hardened to RC63 without becoming brittle compared with RC61 for O1) which gives some advantage in edge retention with no loss of edge taking ability. Clifton use O1 but then put the irons through a cryogenic heat treatment to achieve a similar end.

All steels can warp, the alloying elements in O1 help with that considerably (at the cost of reducing the optimum hardness), bringing production wastage due to warping down from maybe 3% for T10 to less than 1%. The irons are carefully checked by quality control at the factory so we should only ever get good ones. Needless to say, if any ever do get as far as a customer they are just exchanged for a checked replacement.

Quangsheng have got very good at making sure that any convexity ends up on the bevel side, leaving the flat side either flat or beneficially slightly concave. I'm not sure how they do it, but the same is true with any of the other reputable makers - Clifton, Ray Iles, Ron Hock etc.

 

[Rorschach]

Quangsheng have got very good at making sure that any convexity ends up on the bevel side, leaving the flat side either flat or beneficially slightly concave. I'm not sure how they do it, but the same is true with any of the other reputable makers - Clifton, Ray Iles, Ron Hock etc.

If you bevel or even partially bevel a blade one one side before heat the natural contraction of the metal during quenching will cause any warp to occur on the side opposite the bevel.

 

[Trafalgar]

Quangsheng have got very good at making sure that any convexity ends up on the bevel side, leaving the flat side either flat or beneficially slightly concave. I'm not sure how they do it, but the same is true with any of the other reputable makers - Clifton, Ray Iles, Ron Hock etc.

If you bevel or even partially bevel a blade one one side before heat the natural contraction of the metal during quenching will cause any warp to occur on the side opposite the bevel.

I seem to recall reading somewhere that the strategy was to see which side warped concave and then grind the bevel on the other side.

 

[D_W]

Quangsheng have got very good at making sure that any convexity ends up on the bevel side, leaving the flat side either flat or beneficially slightly concave. I'm not sure how they do it, but the same is true with any of the other reputable makers - Clifton, Ray Iles, Ron Hock etc.

If you bevel or even partially bevel a blade one one side before heat the natural contraction of the metal during quenching will cause any warp to occur on the side opposite the bevel.

I seem to recall reading somewhere that the strategy was to see which side warped concave and then grind the bevel on the other side.

I believe iles suggests they do that with their chisels.

My experience hardening a few slotted irons has been for the hollow to end up opposite of a pre cut bevel. Who knows if it's 100% of the time, though.

 

[Trafalgar]

If you wait, I believe you'd grind the right side every time as long as the person checking doesn't confuse concave with convex.

 

[patrickjchase]

I think what Chris is driving at is that T10 optimises slightly harder than O1 (it can be hardened to RC63 without becoming brittle compared with RC61 for O1) which gives some advantage in edge retention with no loss of edge taking ability. Clifton use O1 but then put the irons through a cryogenic heat treatment to achieve a similar end.

Through-hardened O1 and W1/T10 have very similar Charpy and Izod (toughness) scores in hardened and tempered state, so I don't think that what you say here is factually true. I think that one possible source of confusion is that like many water-hardened alloys, W1/T10 can be face-hardened, such that the core converts to pearlite or possibly bainite instead of martensite and remains quite soft and tough. When treated that way a W1/T10 part can indeed be much tougher than an O1 equivalent with similar surface hardness, but that's not what Quangsheng is doing and not relevant to this discussion. Face-hardened W1 is used quite a bit for industrial coining for exactly that reason, though.

All steels can warp, the alloying elements in O1 help with that considerably (at the cost of reducing the optimum hardness), bringing production wastage due to warping down from maybe 3% for T10 to less than 1%. The irons are carefully checked by quality control at the factory so we should only ever get good ones. Needless to say, if any ever do get as far as a customer they are just exchanged for a checked replacement.

Again, all true except for that part about "reducing.. optimum hardness", which is not supported by objective data. As a more practical example Hock for example ships O1 irons at Rc62, that are every bit as tough as any similar W1/HCS iron I've seen.

You also mentioned regrigeration in another post. What that does is to convert retained austenite to martensite and thereby improve hardness at any given temper state (and therefore toughness). Once again I don't know of any major difference between O1 and W1 in that respect - they are both known for having rather low retained austenite fractions to begin with, so the benefit is rather limited. Neither needs refrigeration to the same degree as some of the air-cooled alloys (and particularly some stainless steels), which can have ~20% retained austenite upon cooling to room temperature. For example CTS-XHP (aka PM-V11) should be refrigerated between austenitization and tempering, per its manufacturer.

Quangsheng have got very good at making sure that any convexity ends up on the bevel side, leaving the flat side either flat or beneficially slightly concave. I'm not sure how they do it, but the same is true with any of the other reputable makers - Clifton, Ray Iles, Ron Hock etc.

There are a few ways this can be done. As somebody else says you can just wait to grind the bevel until you see which way the warp goes. I've heard rumors that in the "old days" skilled heat treaters were known to play games with quenchant flow/agitation to bring one face down faster than the other and thereby control warp direction (if cooling is isothermal then there is no warping, so by controlling temperature differences you can selectively warp). As another poster said shape also influences warp, but the sheer number of bellied chisels on the market suggests that the presence of a bevel is far from being a guarantee of favorable direction.

 

[Rorschach]

Quangsheng have got very good at making sure that any convexity ends up on the bevel side, leaving the flat side either flat or beneficially slightly concave. I'm not sure how they do it, but the same is true with any of the other reputable makers - Clifton, Ray Iles, Ron Hock etc.

If you bevel or even partially bevel a blade one one side before heat the natural contraction of the metal during quenching will cause any warp to occur on the side opposite the bevel.

I seem to recall reading somewhere that the strategy was to see which side warped concave and then grind the bevel on the other side.

There's no reason you can't do that too, but depending how they grind and do their QA it could be less efficient. I suspect that most would grind a the bevel first, harden, then hone.

 

[D_W]

If you wait, I believe you'd grind the right side every time as long as the person checking doesn't confuse concave with convex.

That's certainly true, but the initial bevel grind is extremely easy to make when the metal is unhardened.

I'm guessing that the modern (US and Canadian) manufacturers like A2 so much because they can mill all of their blades out of flat stock, mill the bevels onto them, harden and temper them and then surface grind them without significant distortion. A real tight pants kind of operation.

My amateurish approach is more of a loose pants operation (plus, I'm kind of curious to see if I ever get burned - some people gamble with money, but I've learned too much about odds in my lifetime to do that - I'll have to stick to bevels).

 

[patrickjchase]

I'm guessing that the modern (US and Canadian) manufacturers like A2 so much because they can mill all of their blades out of flat stock, mill the bevels onto them, harden and temper them and then surface grind them without significant distortion. A real tight pants kind of operation.

Yes, air-hardening alloys like A2 (and PM-V11/CTS-XHP) are very stable compared to their water/brine- and (to a lesser degree) oil-hardening counterparts. IIRC Thomas L-N has said that that was a consideration in their move to exclusively offer A2 for almost all of their plane irons and chisels.

I would point out that a very well-known Canadian manufacturer continues to offer O1 for almost all of their plane irons and chisels (and 1095/HCS for their scrapers), so their processes are clearly compatible with less stable alloys. I like their O1 stuff a lot for low-angle use in particular.

 

[matthewwh]

You also mentioned regrigeration in another post. What that does is to convert retained austenite to martensite and thereby improve hardness at any given temper state (and therefore toughness). Once again I don't know of any major difference between O1 and W1 in that respect - they are both known for having rather low retained austenite fractions to begin with, so the benefit is rather limited. Neither needs refrigeration to the same degree as some of the air-cooled alloys (and particularly some stainless steels), which can have ~20% retained austenite upon cooling to room temperature. For example CTS-XHP (aka PM-V11) should be refrigerated between austenitization and tempering, per its manufacturer.

As I understand it cryo treatment just extends the initial martensite conversion phase after the quench and (more importantly in the case of O1) encourages the precipitation of ultra fine carbides which benefit edge retention. I believe it is multiple tempering that converts a proportion of the retained austenite with each step, which is why it is routinely done with air hardeners but not needed for oil or water hardening steels. There are of course many other factors - soak time - carbon diffusion etc. Metallurgy is, quite literally, a whole science and a whole craft, I doubt that one lifetime is enough to understand it.

That said, it comes as no surprise that Ron is able to tease an extra point out of O1, that guy is just a magician with steel. Either way, we aren't talking right or wrong, these are just subtly different approaches to finessing the last little smidge of performance out of the material and give the end user the best possible experience. Like Michelin starred chef's competing to wow the gastronomists with the lightness of their souffle or the flavour of their sauces, we have grubby metalbashers trying to impress us with their edge taking and retention.

I suspect we may have left poor Billy wishing he'd never asked! #-o

The bottom line is that, as woodworkers, we are thoroughly blessed to have so many wonderful hand tool manufacturers worldwide all working their socks off to compete on quality. The manufacture of woodworking tools probably hasn't seen a golden age like this since the 1800s, enjoy every moment of it!

 

[patrickjchase]

As I understand it cryo treatment just extends the initial martensite conversion phase after the quench and (more importantly in the case of O1) encourages the precipitation of ultra fine carbides which benefit edge retention. I believe it is multiple tempering that converts a proportion of the retained austenite with each step, which is why it is routinely done with air hardeners but not needed for oil or water hardening steels. There are of course many other factors - soak time - carbon diffusion etc. Metallurgy is, quite literally, a whole science and a whole craft, I doubt that one lifetime is enough to understand it.

I was a mechanical engineer in a prior career, and have some formal training in metallurgy, but IMO the best resource for somebody interested in this but lacking formal background is Verhoeven's Ebook for knifemakers: http://www.hybridburners.com/documents/verhoeven.pdf. He later published a proper book entitled "Steel Metallurgy for the Non-Metallugist", but it's expensive and the Ebook is quite accurate and comprehensive.

He deals with retained austenite and refrigeration on pp. 137-138. The short version is that it really is done to convert retained austenite to martensite.

What you say about carbide precipitation is actually true, but in an indirect way such that we are both right. Using a higher than normal hardening temperature with certain steels both encourages such carbide formation and causes increased retained austenite. The maker must then refrigerate to convert the resultant retained austenite before tempering. The topic is treated in figure 5-12 and accompanying text on p. 80 in this ASM book: http://allaboutmetallurgy.com/wp/wp-content/uploads/2016/12/Tool-Steels.pdf

Multiple tempering cycles is a much older and less effective way to deal with retained austenite.

 

[patrickjchase]

This will probably come across snobbish, so I'll use properly British examples to try to win back the "home crowd"...

That said, it comes as no surprise that Ron is able to tease an extra point out of O1, that guy is just a magician with steel.

Ron has been an indefatigable champion and resource for our community, and we would all be far worse off if not for his fortuitous early partnership with Krenov and co, leading to his career as a blade maker.

With that said, as a "metal magician" he isn't playing in the same league with the engineers at Rolls Royce who do turbine blade metallurgy, the armor developers who were formerly located at Chobham Common, or the people working on heat exchangers for SABRE (https://en.wikipedia.org/wiki/SABRE_(rocket_engine)). For that matter he probably isn't on the same pitch with the French vendor that heat-treats his irons. His results are top-notch, but so are plenty of others. Heat treating O1 is a very well-understood process. You or I could buy top-quality normalized O1 stock, shape it to taste, send it to the same HT vendor he uses (or another), and get similar results.

Most people choose to temper O1 a bit softer than he does because they prefer a somewhat different hardness/toughness/wear-resistance tradeoff, not because he's achieving some sort of magic.

I actually give him a lot of credit for knowing what he's really good at (understanding and servicing his market) and contracting the metallurgy out to professionals.

 

[shed9]

To be fair, contrasting a man producing cost effective and well respected blades for cutting wood in a predominantly hobby environment to single crystal cast alloyed components that are subsequently electron beam plasma deposited with a ceramic coating in a purpose built environment costing over £100m for that one sole purpose is (using another British example), simply not cricket.

In his field, comparative to other blade manufacturers and to the hobby crowd, he get's to call himself wizard as far as I'm concerned. Is he Oz's head wizard? probably not, but a wizard none the less.