MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

A place to share your experience with our Mule Team knives.
Steeltoez83
Member
Posts: 387
Joined: Sat Aug 01, 2020 8:51 am

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#81

Post by Steeltoez83 »

I work overnight so 3 am is normal for me. I was chatting with triple b Shawn briefly around 2 am my time midnight his time. The rex76 has 17% carbide volume which is the same as cpm 10V. Overall the 10V has more harder carbides, but the rex76 has finer overall carbides based on the samples I gave him. I gave him a new10V pm2 to directly compare to his 15V so he could show the comparisons if he chose to. The rex is interesting becuz it doubles the carbide volume of rex45 and obtained several Rockwell points higher too. Based on our brief convo id say he's a fan of rex76. Or should I say the attributes pique his interest at this point. I know I'd buy rex76 if it was offered in a production folder.
"Nothing is built on stone; all is built on sand, but we must build as if the sand were stone."
User avatar
Ramonade
Member
Posts: 3049
Joined: Sun Aug 15, 2021 3:45 pm
Location: NE France

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#82

Post by Ramonade »

Thanks to both of you for the hardness data ! It's only two samples, but at least the number we've got from those are coming from legit tests !
:respect In the collection :respect : Lots of different steels, in lots of different (and same) Spydercos.

Robin. Finally made an IG : ramo_knives

MNOSD member 004* aka Mr. N5s :face-clouds
User avatar
standy99
Member
Posts: 2205
Joined: Sat Jul 22, 2017 11:07 am
Location: Between Broome and Cairns somewhere

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#83

Post by standy99 »

Ramonade wrote:
Fri Dec 02, 2022 5:59 am
Thanks to both of you for the hardness data ! It's only two samples, but at least the number we've got from those are coming from legit tests !
When 2 samples are the same it’s a good indicator that that’s the hardness for most, if not all of them….
Im a vegetarian as technically cows are made of grass and water.
aprivetera
Member
Posts: 34
Joined: Tue Jun 28, 2022 11:43 am

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#84

Post by aprivetera »

Took off the paracord on the Rex 76 mule to put on scales and there are more rust spots than I expected:

Image

Strangely enough only on one side. Slathered the knife in mineral oil and threw the Halpern scales on while I order some thinner felt, as the stuff I found was too thick for between scales.

What are good ways to safely remove that rust without harming the steel too much? Would it be better to just remove the scales monthly and put a coat of mineral oil the knife now that rust has started?
User avatar
standy99
Member
Posts: 2205
Joined: Sat Jul 22, 2017 11:07 am
Location: Between Broome and Cairns somewhere

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#85

Post by standy99 »

aprivetera wrote:
Fri Dec 02, 2022 5:11 pm
Took off the paracord on the Rex 76 mule to put on scales and there are more rust spots than I expected:

Image

Strangely enough only on one side. Slathered the knife in mineral oil and threw the Halpern scales on while I order some thinner felt, as the stuff I found was too thick for between scales.

What are good ways to safely remove that rust without harming the steel too much? Would it be better to just remove the scales monthly and put a coat of mineral oil the knife now that rust has started?
This was the whole reason I started epoxying scales on as live tropical and was always taking scales off to light rust spots…

Scotchbrite pad will do it usually.
Or
One of these works a treat
Image
Im a vegetarian as technically cows are made of grass and water.
User avatar
Bolster
Member
Posts: 5573
Joined: Sat Mar 03, 2007 1:27 pm
Location: CalyFRNia

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#86

Post by Bolster »

aprivetera wrote:
Fri Dec 02, 2022 5:11 pm
...What are good ways to safely remove that rust without harming the steel too much?...

In one of his videos, Shawn/BBB recommends using Barkeeper's Friend to remove corrosion/rust on a knife...and he specifically mentioned "NOT Flitz."
Steel novice who self-identifies as a steel expert. Proud M.N.O.S.D. member 0003. Spydie Steels: 4V, 15V, 20CV, AEB-L, AUS6, Cru-Wear, HAP40, K294, K390, M4, Magnacut, S110V, S30V, S35VN, S45VN, SPY27, SRS13, T15, VG10, XHP, ZWear, ZDP189
User avatar
Traditional.Sharpening
Member
Posts: 282
Joined: Thu Mar 02, 2023 12:29 am

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#87

Post by Traditional.Sharpening »

JRinFL wrote:
Tue Oct 04, 2022 4:58 pm
Team Sick wrote:
Tue Oct 04, 2022 1:03 pm
Since this is a tool steel, does it make sense to force a patina on the tang with like Ferric Chloride or Mustard to protect it from rusting?
You could use something like EDCi which is a safe blade protectant or something less expensive like vasoline or mineral oil. All are simple and inexpensive. The only reason to force a patina is if you enjoy the look and there’s nothing wrong with that either.
This is simply not true in the least, forcing a patina is very helpful at preventing red rust. Black rust (patina) helps to hold oil and by doing so will also add additional rust preventative qualities. I strongly recommend polishing the blade on a 1000 grit waterstone and THEN forcing a patina, you will likely never see deep penetrative rust under most conditions after doing so.
bobartig
Member
Posts: 106
Joined: Mon Aug 08, 2022 4:47 pm

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#88

Post by bobartig »

So, if someone were to attempt this, what would you use to apply a forced black rust patina to Rex76?
bobartig
Member
Posts: 106
Joined: Mon Aug 08, 2022 4:47 pm

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#89

Post by bobartig »

Spent a couple solid hours whittling away at African Wenge with my Rex 76. Tried CPM 20CV and M398 at this, and both of those steels didn't hold up for very long before the edge rolled or it just wouldn't bite easily. The effort ramped up very quickly.

Rex76, tho' is a BOSS when it comes to maintaining a workable edge against this extra-hard material. This is after I carved half a micarta scale in between (then gave up again because that stuff is *nasty*). I can see a bit of wear right at the heel of the blade where I've been working it the most, but it's held up remarkably well.

Image
User avatar
Traditional.Sharpening
Member
Posts: 282
Joined: Thu Mar 02, 2023 12:29 am

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#90

Post by Traditional.Sharpening »

bobartig wrote:
Thu Mar 23, 2023 10:21 am
So, if someone were to attempt this, what would you use to apply a forced black rust patina to Rex76?
I like to use grapefruit and slice into big chunks which then get skewered together, then you simply stick the knife into the fruit and leave it there for a few hours or so. You may get some light red rust in spots but you can clean this off with barkeeper's friend. The nice thing about this route is it will give a nice mottled look where you won't be so anal about little bits of rust appearing over time. Ideally you will use a rust preventative on the tang as well, I like Eezox, dries to touch and stays working for a long time. You could just use this without the patina as well, it's very effective.
Screenshot 2023-03-24 at 10.21.42 AM.png
bobartig
Member
Posts: 106
Joined: Mon Aug 08, 2022 4:47 pm

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#91

Post by bobartig »

I like to use grapefruit and slice into big chunks which then get skewered together
Grapefruit?!?! :squinting-tongue I thought I was going to have to buy hydrochloric acid, or gun bluing agent (and end up on some weird list). Haha! Good deal! I've got three citrus trees in the backyard, so I definitely have access to that. Will keep this in the arsenal to try at some point.

Also, I think I might have had some pantina already from chopping down banana trees with the Rex76, but a lot of it dissolved away when I applied mineral oil and wax. Anyway, I'm warming slightly to these tool steels in a fixed blade format (still not sold on them for folders!), thanks for the info and pics. They're helpful for someone who has mostly avoided stainless before getting into Mules.
JRinFL
Member
Posts: 6145
Joined: Wed Nov 18, 2015 10:30 am
Location: Unfashionable West End of the Galaxy (SE USA)

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#92

Post by JRinFL »

Traditional.Sharpening wrote:
Sun Mar 19, 2023 2:26 pm
JRinFL wrote:
Tue Oct 04, 2022 4:58 pm
Team Sick wrote:
Tue Oct 04, 2022 1:03 pm
Since this is a tool steel, does it make sense to force a patina on the tang with like Ferric Chloride or Mustard to protect it from rusting?
You could use something like EDCi which is a safe blade protectant or something less expensive like vasoline or mineral oil. All are simple and inexpensive. The only reason to force a patina is if you enjoy the look and there’s nothing wrong with that either.
This is simply not true in the least, forcing a patina is very helpful at preventing red rust. Black rust (patina) helps to hold oil and by doing so will also add additional rust preventative qualities. I strongly recommend polishing the blade on a 1000 grit waterstone and THEN forcing a patina, you will likely never see deep penetrative rust under most conditions after doing so.
Thanks for the correction.
"...it costs nothing to be polite." - Winston Churchill
“Maybe the cheese in the mousetrap is an artificially created cheaper price?” -Sal
Friends call me Jim. As do my foes.
M.N.O.S.D. 0001
User avatar
Traditional.Sharpening
Member
Posts: 282
Joined: Thu Mar 02, 2023 12:29 am

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#93

Post by Traditional.Sharpening »

bobartig wrote:
Fri Mar 24, 2023 12:37 pm
I like to use grapefruit and slice into big chunks which then get skewered together
Grapefruit?!?! :squinting-tongue I thought I was going to have to buy hydrochloric acid, or gun bluing agent (and end up on some weird list). Haha! Good deal! I've got three citrus trees in the backyard, so I definitely have access to that. Will keep this in the arsenal to try at some point.

Also, I think I might have had some pantina already from chopping down banana trees with the Rex76, but a lot of it dissolved away when I applied mineral oil and wax. Anyway, I'm warming slightly to these tool steels in a fixed blade format (still not sold on them for folders!), thanks for the info and pics. They're helpful for someone who has mostly avoided stainless before getting into Mules.
You can use the fancy stuff if you're up for the risks and take precautions. They tend to give the best results in some ways but my intention is not perfection but rather the opposite... sort of controlled chaos where I don't fret over imperfections because the whole surface is one big eyesore in some ways. You'll see some rust on that blade of mine, I've never bothered to remove it because it just doesn't bother me like it would if I tried to keep a polished finish pristine. I've never really oiled this knife either because I use it in the kitchen around food. It's 52100 @ 60-62 steel, so very rust prone.
TTFulltimer
Member
Posts: 111
Joined: Wed Feb 01, 2023 12:25 pm

Re: MT33 CPM REX 76 -First Impressions, Performance, and Testing Thread

#94

Post by TTFulltimer »

I travel full time so I am calling my Rex 76 Mule my Camp Knife. It is very sharp with a polished edge. Today I took a far in the back of the freezer package for dinner. It was a beef filet that had gotten a little freezer burn. While it was solid as a rock, I took out the Camp Knife and shaved all around and on the cut sides to take off any of the burned portions. Basically shaved a very thin slice, almost see through, from all portions of the meat. It was really easy and a pleasure to use for that. And being a mule with an epoxy attached handle there was not chance of any meat juices penetrating. I will be grabbing that more often for food prep. My razor sharp larger kitchen knives get a lot of use. But this job needed something smaller to do the trimming.
Just a crotchety old curmudgeon who has seen a thing or two
Post Reply