So where are people getting troublesome AEB-L?

I don't think there is another steel out there that has as many threads on bladeforums about warping during heat treat as AEB L does.

I know that it warps on me when I ground before hardening and I do my own heat treat. So much so that I don't grind AEBL pre-hardening now and I hate grinding post heat treat.

Regarding what Ben said I don't think he is far off. If anything this thread backs up his statement. I briefly skimmed the posts again and it looks like everyone that states they do their own heat treat mentioned warping and those that don't have issues state they have someone else do the heat treat.

Back on topic I have no idea who may have been putting out bad steel. I've only bought AEBL from Aldo, who is a stand up, and I don't believe he is to blame for the warping issues I read about. I think it is just a characteristic of this steel.

-Clint
 
It may also be that this steel often gets used for thin knives. And of course, it could be getting warped by the pros as well, if they straighten it, how would you know?
 
I think Kevin hit the issue - AEB-L is used more on thin blades than many other alloys and thin stuff does tend to have more warp issues. I've been using AEB-L, and after the first batch I've not had any issues with warp, and the first batch was the way I put in dry ice slurry.

AEB-L is good stuff for the price. I've used S30V a couple of times and it's good stuff, and would like to try some S35V, but not at all sure it's really worth the price difference. Unless of course, a customer fits the "price doesn't matter" group.

Ken H>
 
Augus7us said:
I don't think there is another steel out there that has as many threads on bladeforums about warping during heat treat as AEB L does.

I know that it warps on me when I ground before hardening and I do my own heat treat. So much so that I don't grind AEBL pre-hardening now and I hate grinding post heat treat.

Regarding what Ben said I don't think he is far off. If anything this thread backs up his statement. I briefly skimmed the posts again and it looks like everyone that states they do their own heat treat mentioned warping and those that don't have issues state they have someone else do the heat treat.

Back on topic I have no idea who may have been putting out bad steel. I've only bought AEBL from Aldo, who is a stand up, and I don't believe he is to blame for the warping issues I read about. I think it is just a characteristic of this steel.

-Clint
Click to expand...

Nobody stated that Aldo was putting out problematic AEB-L, ALDO stated others were. Feathers have been (understandably) ruffled.
 
Perhaps I could have worded that better. I read Aldo's little diatribe and have no idea who he was talking about or if he even knows himself. Could just be word got back to him and he felt he was getting blamed or something. Who knows.

What I was trying to get across was I've not bought AEBL from anyone but Aldo so I can't help in that regards. Aldo probably could have worded his post a little better also, but hey, folks have bad days and I have had the pleasure of meeting Aldo personally and can say he goes out of his way to keep his customers happy. In fact I still owe him a beer from that meeting :D

-Clint
 
AEB-L warps from grinding quite often, it is worse when not hardened but still occurs when hardened. I have found that sharp belts and balancing grinding, even when counterintuitive, works well. Warp also occurs in the quench, so I quench at full thickness into plates- and then move into another set of thin plates to immerse in the dry ice slurry.
A lot of what I see is that it's susceptible to burnishing expansion, which is what I call it when a somewhat dullish belt smears rather than cuts the surface, causing the surface to expand on that side, and bowing to occur away from the point of abrasion.
One thing I've found that helps, is to have a cold quench plate by the grinder, and press the positive side of any occurring warp onto the plate, which can actually shrink that side a bit due to uneven cooling. It's actually somewhat similar to a process by which sori is adjusted after quench, in nihonto.
I keep meaning to track a blade sometime, to see if it has a tendency all the way through manufacture, to warp to one side dominantly. Offhand I can't say for sure whether this is common, but if so, that would tend to support the theory of causation by residual tension from "coiled" steel.
 
All aebl is made for cutlery. The initial casting must fall within very strict tolerances because it is impossible to roll dirty steel into strip. Most aebl is rolled to very thin material made for disposable razor blades. Aebl is always clean material.

Warping occurs with all steels. All steels change size when heat treated which causes warping. Steel does have a memory and can move to the original coiled shape. Most warped blades are easily straightened by over bending in the opposite direction and tempering, or by heating the spine a little with a torch while bending the blade past straight.

Hoss
 
I have been meaning to try AEB-L. I currently make kitchen knives from 52100 and absolutely love the stuff but people keeo requesting stainless. About to pull the trigger on AEB-L because it is so cheap but a local maker I respect a lot uses 14c28n so I've been considering that too but it is a bit more. Cpm154 looks nice too but i wonder how hard it would be for the end user to thin over time. Either way I grind all my blades laser thin and all after HT but have never seen a hardened blade warp while grinding. Also haven't tried aebl yet.
-Comet
 
How thick and heavy are the quenching plates people are using?

3" thick aluminum quench plates works well at keeping it flat.
 
I might mention that the majority of the 80 some odd AEB-L pieces I've sent/received from Peters' were mostly only profiled, and not ground on one side or the other, except for some minor de-burring.
 
Comet-Sharp: do you have a source for 14C28N in thin strips? I REALLY like that stuff, but it's getting hard to find these days. Shucks, even AEB-L is hard to find in the thin stock of .070" range.

Ken H>
 
Ken, I was going to call Sheffield supply about the 14c28n. I prefer to make my kitchen knives from .0937" stock. There is a lot to grind but it allows me to give them a good bit of food release in the grind, i grind in distal taper after the bevels are set. I guess it's more of a "workhorse" grind. Even been considering .110" stock. I still get them scary thin behind the edge.
 
I've had it warp both before and after heat treat. But as Salem pointed out its really a matter of changing the method of grinding. Switch belts and sides often and keep it cool. I found grinding with a backer board behind the thin pieces keeps them straight when grinding.

The only one i've had warp beyond repair was from being placed in the dry ice a bit more forceful than ought to be done.
 
Ahh yes, some times getting into the dry ice can be tough on them, that's why I've gone to clamping one or more blades together between 1/4" mild steel plates, then placing in dry ice slurry. Works well.
 
AVigil said:
How thick and heavy are the quenching plates people are using?

3" thick aluminum quench plates works well at keeping it flat.
Click to expand...

Adam I use 1/2" plates that are about 3"x14" because I had about 4 square foot of half inch available to me when I got my oven. I believe the usual recommendation is 1" with the primary purpose being you can do more blades without too much heat build up. That said I use compressed air while the blade is in the plates and if they get to hot I just dunk them in water between quenches.

I've never had to much of an issue with blanks warping if I grind post heat treat but I do tend to grind a little on one side then switch back and forth. I do that with carbon steels also. I did have occasional blades come out of the dry ice warped so I started clamping the blades together with c clamps then putting them in the dry ice and this has worked out fairly well for me and I can produce a blade with little or no warp.

On the occasion that I do get one out of the dry ice that is warped I use a special peening hammer to straighten them as described by Eduardo on here and in Murray Carter's book. I found that to be the most accurate and least damage prone way to straighten them I have tried. Prior to that I have used all the normal methods mentioned in threads here though I could not bring myself to put a torch to a heat treated blade, I'm a little surprised Hoss mentioned that!

-Clint
 
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