CPM 154 with grainy surface

RandyR

RandyR

KNIFE MAKER
All,
I could use some insight from those that have used CPM 154. I have made a few blades from it and most were finished with a 400 to 600 grit satin with a couple to 1200. Today, I was attempting to bring a blade up to 1200. When I hit 600, I began to see a strange looking texture on the entire surface of both sides. At 1000, it was very noticeable and reminded me a bit of the orange peel looking polished D2 blades I used to make. This was new bar of steel but the one other blade made from it seemed fine. It was heat treated by Paul Bos Heat Treating (after he left) and looked like normal after heat treat. It must have hardened correctly or they would have told me so I am puzzled. I would show a picture but it does not show up on any I have attempted to take. I have some more from the same bar heat treated at the same time so I will take a look at them soon to see if this is isolated. Has anyone else seen a strange texture on the suface of this steel?
Thanks,
Randy
 
RandyR said:
All,
....This was new bar of steel but the one other blade made from it seemed fine. ....
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This is the strange part of the puzzle. The obvious suggestions about a poor batch go out the window. What might be different about the two? Heat treat? New finish sanding method? Any buffing done? Any remote chance of steel mix-up?

A PITA I know, but an interesting puzzle.

Rob!
 
Rob,
It is possible I did mix up knives from different bars and the one that looks good came from another piece. I am very careful not to mix up steel types but I could certainly have mixed up pieces from different bars of the same type. I made batch of about 12 blades with most from one bar but a few from another so it could be. Relative to heat treat, I suspect they were done in one batch but I really don't know. As far as finishing methods, nothing has changed. I don't do any buffing anymore and the sanding is consistent in terms of type of paper, lubricant and pressure. I do suspect there is something wrong with the bar. I have had 154CM have finish problems before (also some ATS-34 once), so maybe it is simply the wrong steel. If so, I have $700.00 of it setting around. Crap.
Randy
 
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I have a batch of cpm 154 now with the same problem. The 5/32" seems to be fine, but the 1/8" has the texture your talking about. I've spent a lot of time on the surface grinder and it's still there.
 
I had the same problem with a supplier whose name I don't want to post. PM me if you would like to know who it was. It was on some 1/8" stuff also.
 
I have not heard of this before. Anything is possible. If anyone got any of this from me, let me know and we'll start tracing the batch back to the mill and factory.
 
I really hope you guys who have had problems have let the supplier know about it. I understand you don't want to crucify anyone publicly, but I'm SURE they would appreciate an email - and maybe even some cutoffs to send to Crucible for analysis.

CPM 154 is normally an outstanding steel - the reason many experienced and respected makers have switched to it exclusively. One of it's best characteristics is said to be its ability to take a fine mirror finish easily. Don't be too quick to give up on it. It should be among the very best - and usually is.

Rob!
 
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Knifemaker.ca said:
CPM 154 is normally an outstanding steel - the reason many experienced and respected makers have switched to it exclusively. One of it's best characteristics is said to be its ability to take a fine mirror finish easily. Don't be too quick to give on it. It should be among the very best - and usually is.

Rob!
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Well said Rob. By all means contact your supplier, CPM-154 is indeed outstanding steel for many reasons, including its fine grain and extremely consitant structure which is what allows it to take such a beautiful polish. There's something weird going on here and the mill needs to know about it.
 
cpm154 is my favorite steel. I have contacted my mill rep to see if they are aware of anything. my mill rep has not heard anything about this so far.
 
Tracy,
I did not get it from you and I am reluctant to say on the web where it did come from. If it helps, I bought it about 1 1/2 years ago. I have also had generally good experiences with it but this last batch is definitely a problem. I wish I did not have so much of it. Everything I can check indicates it is probably still good for a user but I have a few blades that were intended to be a bit more elaborate and this simply makes that impossible. I have another that is showing a streak of what I surmise is a high concentration of carbide right in the middle of the blade. It is a very shiny spot that stands out like a beacon even after hours with stones and sandpaper. Not a good week. I do intend to contact the supplier but if other's experience is an indicator, there will be no joy.
Randy
 
Make test knife out of the bad stuff and beat the living snot out of it. If it performs like it normally does, you could use it for beaters and possibly knives with coated blades.
 
The mill has an interest in testing a sample. Do you have a piece with the heat treat stamp on it?
Maybe I can get a piece switched out for you..

RandyR said:
Tracy,
I did not get it from you and I am reluctant to say on the web where it did come from. If it helps, I bought it about 1 1/2 years ago. I have also had generally good experiences with it but this last batch is definitely a problem. I wish I did not have so much of it. Everything I can check indicates it is probably still good for a user but I have a few blades that were intended to be a bit more elaborate and this simply makes that impossible. I have another that is showing a streak of what I surmise is a high concentration of carbide right in the middle of the blade. It is a very shiny spot that stands out like a beacon even after hours with stones and sandpaper. Not a good week. I do intend to contact the supplier but if other's experience is an indicator, there will be no joy.
Randy
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All,
When Tracy asked to see if I had some with heat treat stamps I went out and removed the last three bars from the shipping container. What I found was two bars clearly marked 154CM and the other had no markings. However, they all have the same color code on the end. The two inch bars I have are colored differently and they do shine up well. Much like the third bar, I don't recall any markings on the other two. It seems that I was sent 154 CM instead of CPM 154. I am looking for my receipt but so far no joy. I am still surprised because I have used a lot of ATS 34 with great finish results and I though the 154CM was similar. Apparently I was wrong. Tracy, thanks for asking the questions. I would not have figured it out so quickly. I am still pissed but at least I know the story.
Randy
 
Randy, as you know 154-CM is not the same as CPM-154. Color codes don't mean a damn thing in my experience.

I truly hope this works out for you somehow. Tracy stands behind what he sells and I hope the folks who sold you this "dirty" steel will, too. I understand that you don't want to name the seller you got it from.

I'm honestly curious if the "dirty" steel HT's and performs to the high standard we expect from the 154-CM/ATS 34/CPM-154 "family" of steels. Would you be interested in trading me a piece of that questionable 154 for a piece of known CPM-154? Just for fun I'd like to grind two blades and have them HT'ed the same, then beat the heck out of them and see what happens.
 
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James,
I have a lot of it so it would be no problem to send a piece to you. The stock is about .220 thick rough and I have been taking it down to about 3/16 before grinding. It is 1 1/2 inches wide. Just PM me with how long a piece you want and where to send it.
Randy
 
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