Rex 121/Maxamet - edge retention comparison.

This video documents a series of edge retention tests between Rex 121 and Maxamet. The video has discussion on the steels, sharpening the steels, and the results of the tests.

[@CedricAda]

Oh man I’ve been waiting for this

[@michaelchristy4982]

Cedric & Ada Gear and Outdoors I’ve been wanting to get it done and posted.

[@neroknives1828]

Cedric & Ada Gear and Outdoors how much was the knife on kick starter? I was going to pick one up, now I think they’re $350 and I feel like that’s more then before.

[@Creelyblades]

A word about the overheated edge. The overheating only came with the final sharpening which happens on the belt grinder at a very low speed. The issue was the type of abrasive belt used. The primary bevel is ground with a belt using a ceramic abrasive, typically those belts only go down to 120 grit. For the final sharpening I used a 320 grit aluminum oxide to set the 30 degree final edge, the problem is aluminum oxide will not cut Rex 121 (which I did not know the time) And unknown to me I heated up the apex, but the blade geometry was especially thin and I did not notice it. The solution is that I was able to locate some 220 grit ceramic belts to put on the final edge, these produced very little heat particularly at the very slow speed that I put the final edge on with. I do suspect that this steel as well as maximet will not respond well to aluminum oxide based abrasives. I strongly recommend using diamond based abrasives

[@jsct6111]

As 2 sharpenings were needed wasnt too bad. These steels are especially prone to this type of damage as they require a lot of grinding time due to the extreme wear resistance perhaps thier fatigue strength is rather low compared to pure carbon steels therefore the apex might also be fatigued from the sharpening before the sharp enough edge is formed. Most likely the initial problem was combination of both factors.. Nice little fix design there ")

[@em4703]

Isn't Rex 121 a high temp tool steel? Can the edge even be overheated just by grinding, or was it more likely some type of fatigue due to pressure and burnishing?

[@jeffhicks8428]

Seems wild to me that someone that has such stuff in their possession, & would be playing around with such stuff and not realize alumina would not be suitable to cut basically the highest abrasion resistant steel could physically possibly be before it's not even steel anymore. Yeah no kidding use diamonds. I don't even use alumina on vastly less resistant steels than this. Any steel with a decent combination of vanadium carbides and especially at high hardness, and especially at finer grits, forget it. Even on some where it will technically cut it's a waste of time and doesn't turn good results. Whereas diamonds gets it done quick and easy (in those cases) and turns much better results. Like, I don't even bother with alumina on something like hap40, even at 320 grit, which is nowhere in the league of rex. It's basically a halfway point between carbon steel and this stuff. Just seems wild to me. I don't own any rex121 and I don't make knives, but I'd never think to try that.

[@harrisquicksilver6595]

Man you & pete & outpost 76 need to be hired as contractors by all the big steel companies for all the information yall develope for all these knives! thanks for your time and wisdom Michael

[@harrisquicksilver6595]

I love how consisitant u are with the details of ur experiments, that is key cause every little thing makes so much of a difference...

[@CedricAda]

And finished. Awesome work and exciting result. I am chomping to put it on my rope test. I am hoping the elements of my test let it sing as well as it can. I may do it without the cutting board and use a cork slab instead.

[@FearNoSteel]

Cedric & Ada Gear and Outdoors end grain cutting board

[@michaelchristy4982]

Cedric & Ada Gear and Outdoors I’m interested to see what results you get. Lots of differences between the tests we do.

[@CedricAda]

From all accounts I don’t think I’ll be able to use the work sharp system on this steel. I remember doing i with maxamet and it being a real process which ate the belt and maybe even burned the edge, in hindsight. So I’ll probably jump straight to 17dps toothy like I did for my more recent maxamet cut.

[@michaelchristy4982]

Cedric & Ada Gear and Outdoors I would think the worksharp would be a problem with Rex 121 and Maxamet.

[@natsyrtm4223]

does it not also cause his s110v results to be less than optimal? or from yours is m390 / 20cv also holding the edge longer?..

[@peterama4591]

i stumbled across this channel while looking at opinel knives and subscribed right away holy crap Michale i can't get enough of watching you do what you do ...im learning so much ..thanks for showing us your skills ...you are a master

[@michaelchristy4982]

Peter Turano I’m glad you found the channel and that you’re enjoying it.

[@zebulunstadler9902]

these are far and away the most interesting videos on the subject, which I have become very obsessed with. thank you again for such great work.

[@michaelcheshareck3275]

Nice test. I just cut up 7900 inches of cardboard the other night with Manix 2’s in S110V, Cruwear, and M4, and that is a lot of cutting. I don’t think most people realize how that amount of cutting starts to fatigue you, and if you have a handle that creates hot spots your hand will be in pain.

[@michaelchristy4982]

Michael Cheshareck yeah, hot spots are a bitch.

[@RCL3]

Thanks for another excellent video. Posting your stone and strop details is a nice and a useful reference.

[@michaelchristy4982]

Rick Larkin I try to give the details for that reason. Glad you liked the video.

[@tofino50]

I've been waiting for this Michael thanks so much,just another video with your professional touch . Now I can't wait to purchase a gray handle with maxamet.

[@michaelchristy4982]

Phil SEYMOUR Maxamet being available in folders is pretty exciting.

[@eugeneBai]

Thanks a lot for great tests!!!

[@Happytrees1]

Great work, Michael. I appreciate it.

[@michaelchristy4982]

Daniel Hawse thank you.

[@mforrest1508]

Very well done as usual sir. Thank you!

[@michaelchristy4982]

Matthew Forrest thank you.

[@SteveKluver]

Thank you much, Michael!

[@jeffreyweber8006]

I was on KZbin to look at something else...I saw this and it was "hold on, drop everything..." lol. Great video as usual, man.

[@michaelchristy4982]

Jeffrey Weber thanks brother.

[@erichusayn]

Very interesting video. Just found your chammel today. Good stuff dude.

[@dtomknivesandgear6635]

New subscriber. Can't believe I am just finding your channel. So glade I did. Keep it up man. Great stuff.

[@michaelchristy4982]

DTOM Knives and Gear my channels been around for years. Check out the dates the videos were posted.

[@dtomknivesandgear6635]

@@michaelchristy4982 I did. I feel like a late bloomer. Definitely a informative and entertaining channel. You have a new fan.

[@chucknunface]

Nice work man.

[@michaelchristy4982]

Chuck Nunface thank you brother.

[@PaulK390S90V]

Hey Michael...so I finally got my .05 and .025 emulsion in and got a cheap but surprisingly awesome leather strop. Now all the knives I've sharpened I take and do the .05 and .025 strops and they all whittle hair now! That was the key I think. That and my other strops had a suede like surface and this one is smooth. Maybe I was filling that super fine edge you need to whittle hairs without realizing and since these new ones are smooth yet real firm it just works. Pretty pumped. And I got a few chosera full size stones and Arashiyama 6k and my Kitayama 8k...so I am finally 100% done with having to get sharpening equipment....or probably not but for now lol.

[@ezekielflores2149]

Im at the drive in right now but this was more intresting to me. Although I found I don't prefer steels like maxamet and rex121, this was still intriguing. I've found maxamet doesn't hold any kind of a super keen edge like m390, which is what I like. Thanks for the video, I always look foward to seeing one of your videos pop up on my feed.

[@PeterC585]

Great video, please if you can test LC200N would love to know your thoughts!

[@jamielahugh8316]

Good video man!

[@michaelchristy4982]

jamie lahugh thank you.

[@neroknives1828]

Thumbs up before it even starts

[@cavtj1]

Thanks for these tests Michael! Your knowledge on sharpening is over the top! I have a question, what angle do you recommend on Maxamet, (Manix 2 & Native 5) for EDC? And also do you recommend a mirror edge or say 600 grit diamond stone? Thanks in advance sir!

[@michaelchristy4982]

cavtj1 I usually use a coarse finish on Maxamet. I run the edge around 30 inclusive, but you would be fine with something at 40 inclusive. It’s up to you with how durable you want the edge bevel. Obviously, the higher the angle, the more durability the edge will have.

[@klebics]

Standing ovation

[@junitorosario1037]

Great video Michael, and the interview on podcast was awesome, but now i am curious to know what type of leather you use to strop! 👍

[@michaelchristy4982]

Junito Rosario I’m glad you liked the video and the interview. The leather I use isn’t so much a brand, but more leather with certain attributes, which varies based on the strop I’m making.

[@junitorosario1037]

Michael Christy ive used buck leather and cow leather,but ive heard horse leather is the best i dont know if its true but im gonna try to get some to try it my self, tried Bark River cbn emulsion .5 micron on both buck leather and cow leather and it harden the crap out of both leathers to a point that the surface is like glass maybe i should have just used basswood like you do. any recommendations you can give me on what type of leather to use will be greatly appreciated and thanks for replying. 👍

[@michaelchristy4982]

Junito Rosario I’m not sure what BRK is doing with their emulsions. I use different leathers for different strops (I use different types, not brands), so making a suggestion is a little difficult.

[@PaulK390S90V]

Very interesting! I wonder if it will keep getting better or if your out of the over-heated steel. Pretty cool man, good thinking on both your parts by getting into fresh steel. And to beat Maxamet is just nuts. I've been doing more sisal rope cutting tests and I would be happy to share my results. I just got 410 cuts on my ZT 0909 before it was getting a little snaggy on paper...I was very happy i didn't get a bad heat treat. That's 3 knives now that I've lucked out on. Cedric got 109 with his 0909 with a convex edge and bad heat treat. In his testing he is getting like a 50% increase in cuts on some steels with a v-edge instead of convex. After always hearing people think convex is better I would have guessed the other way around. I also got 120 cuts on my spyderco Tenacious with shit 8cr13mov steel and I was very surprised. I think he got like 40 or 50 in other brands 8cr with convex edges. I know our tests are different and tons of variables but I'm happy with my results and can't change it up now for consistency sake! I tell you though that 3/8" sisal rope isnt easy to cut and since I have mirror edges up to 10k chosera and my last strop .1 micron I noticed I had to do all push cuts instead of like a saw cut. Maybe that has something to do with it. I will have to stop at a 1500 diamond and then go to strops and see how that changes. And also do tests with free hand edges! Pretty excited to have a new area of knives to dive into! Great video man good luck with further testing!

[@michaelchristy4982]

Paul Lonardo good to hear about your testing. Glad you liked the video.

[@littlewoody5539]

Good video .

[@michaelchristy4982]

little woody thank you.

[@wrjames38]

Just watched complete video and found it very interesting. Obvious for you being at the forefront of this steel...worth the time and cost. But @ 3X the cost of a Spyderco Mule Maxamet (with Halpern scales) just not reasonable for the average knife user at only 5-10% increase in cutting! Maybe spyderco will take notice and make a Mule or use Rex 121 on a popular folding platform in the future. Thanks for your time and efforts.

[@bumstudios8817]

Would love to see a test like this on sandrins tungsten carbide

[@FearNoSteel]

First, number one fan!

[@convex7456]

Big Brown Bear u gonna get 121?

[@FearNoSteel]

.308or5.56? I'm more curious about other steels currently

[@convex7456]

Big Brown Bear bravo 1.2 in 3v elmax or 35vn?

[@FearNoSteel]

.308or5.56? Elmax but I think you would like 3v more

[@neroknives1828]

Big Brown Bear 🐻

[@westsenkovec]

This was more interesting than many movies I saw lately. The plot twist was better too. Prior to sharpening, did you dull the edges the same way, by dragging them across the stone? Does that do a bigger damage since they have a vary high hardness and they are brittle? Was there a significantly higher chipping damage compared to other steels?

[@michaelchristy4982]

West Senkovec I always try not to drag the edges on stones to dull them. I’ve done it that way, but I prefer dulling them naturally. I didn’t run into any chipping damage with these tests.

[@canvasbagfight]

Sorry if you've answered this before but do you get hair whittling off high carbide steels finishing on ultrafine ceramics or do you have to go to sub-micron diamond strops?

[@michaelchristy4982]

Wes W the knives might occasionally get to hair whittling off the stones, but I take them through strops because it gives a better edge.

[@american1911]

First, I like your no-nonsense approach. In the video it appears that you are cutting the cardboard in the direction of the corrugations as apposed to across the corrugations. Wouldn't that cause a large variable? Each cut would have three layers but the glue in the cuts would be hit and miss?

[@michaelchristy4982]

American 1911 it might cause a variable, but this isn’t Catra testing. There will be some variables. Life has some variables, so I don’t mind too much. This is simply a test to show the result I got, with as much transparency as possible, so that you, the viewer, can qualify the test for yourself.

[@astrayael]

Thanks for the info and testing. Compared to the MT, how does the Mako compare in edge geometry?

[@michaelchristy4982]

astrayael the MT is thicker behind the edge. (Probably due to all the testing I’ve done with it.)

[@astrayael]

Michael Christy Interesting. Given the shallow nature of the grind on the Mako, I would've thought the MT was thinner. Appreciate the response.

[@michaelchristy4982]

astrayael well, the MT is thicker behind the edge. As far as spine thickness, I would need to check both blades.

[@jeffhicks8428]

I try to be simple in how to sharpen high carbide steels like that. Get a good edge on it, get it cleaned and it's good to go. Its tricky to be testing two different knives and be talking about consistency. I find it odd. It's quite arbitrary based on the inherent differences in the blades being tested, regardless of the steel that's used. personally I find both of these steels to above the usability threshold for even high resistance knife steels. It doesn't really make much sense over something like k390 or zmax. I'd be interested in seeing someone try laminating some of that 15v or maxamet. Gimme some lc200n laminated 15v and Ill get excited. Rex121 I don't even bother with, even for a smaller lighter use blade.

[@jovonntrujillo1143]

Your right first I’ve really heard about Rex since cliff stamp! Mind bending stuff! Do u think with a different heat treat max could cut even more? Was wondering because I feel like spyderco does a great ht but never really goes for maximum performance!

[@michaelchristy4982]

Jovonn Trujillo I’m not sure. It’s pretty extreme as it is.

[@jovonntrujillo1143]

Michael Christy hey Michael I bought cktg diamond stropping compound and having trouble applying it to my basswood strop.any tricks u use? Just having a hard time keeping the compound consistent and sticking to the wood. Thanks. Just remember u saying something about sanded wood verses as is.

[@michaelchristy4982]

Jovonn Trujillo is the compound you’re using oil based, or water based? (Is it in a syringe, or spray bottle?)

[@jovonntrujillo1143]

Michael Christy it’s in a syringe! Thick as well!

[@michaelchristy4982]

Jovonn Trujillo it’s oil based. If you’re going to use it on leather, apply oil to the leather first, let it dry, then put the compound on. On basswood it should be fine to just put it on, (a thin layer) and go.

[@matrix5175]

Just wandering if you have any advice you could share with me on a problem I have while sharpening. I have sharpened on stones for most of my life and can get a knife very sharp, although not at sharp as you. My problem is that I have trouble getting the angle even on both sides of the knife. I notice that you sharpen the same direction by switching from your right hand for one side of the blade, then your left hand for the other side. I don't sharpen that way but was wandering if you do that to help keep the angle the same on both sides or if that was just the way you learned to sharpen. I sharpen by going away from my body on the stone one direction and then back towards my body on the stone for the other side of the blade. I can keep the angle the same, but it just does not produce the same bevel/edge on both sides of the knife. Sorry for the long post, but thanks for any advice you can give on this subject.

[@michaelchristy4982]

matrix5175 actually, I sharpen both ways. I can switch from right to left bringing the blade towards me the whole time, or switch back and forth (towards me and away from me) in the same hand. (I show that in my Full Sharpening video of an Opinel 9). However, I’m a very visual sharpener and more often switch hands keeping the blade towards me. Something you can do to practice keeping the angle the same is, use a guided system to reprofile and set the angle. Then sharpen the knife freehand and try to imitate the angle that’s there. Repeatedly sharpen the knife. If you screw up the angle, reprofile and start over. I suggest doing this with a knife you don’t care about... an Opinel is a good choice for this.

[@matrix5175]

Michael Christy I appreciate your response and suggestion. .....for some reason when I sharpen towards me, the edge always seems to be bigger on that side of the knife than when I am sharpening away from me. For the knife edge to "look" the same on both sides, I generally have to hold the knife much higher about 25° pulling towards me, and then hold the knife about 5° degrees pushing away from me. Keep up your great videos, I really enjoy watching them!

[@matrix5175]

Michael Christy Thanks again for your response and your suggestions. I just wanted to state for the record that I didn't mean to infer you couldn't sharpen other ways than what I mentioned, I was just wondering if you preferred sharpening or thought it was more beneficial to sharpen with your right hand, then your left with the knife coming toward you. I totally believe you could stand on your head and sharpen upside down and still get a knife sharper than most anyone. Anyway, from your suggestion I bought some coarse and extra coarse stones to set the bevel on both sides of the blade before I started sharpening and that has made a world of difference. I've never had coarse stones before so I always started with a medium stone and I think that is why I was having so much trouble keeping my bevels symmetrical on each side. Learned so much from your videos already. ....so thanks and I always look forward to your next video!

[@neroknives1828]

Man I can’t cut a free hanging paper towel all the way. I can get it half way. Do u remember your edge finish in that cut demonstration video? I think toothy edge would work best, but allot of props for getting your edge that clean. Really difficult

[@michaelchristy4982]

Vinny Nero it is really hard to do. Don’t remember the finish.

[@neroknives1828]

Michael Christy man I’m so close. The steel is only 8cr13 but. It’s was so bam close. I think I’ll get it in a couple days.

[@gvigil609]

Is the rex 121 thicker it looks as though the edge geometry might be quite different

[@michaelchristy4982]

gabe v the blade geometry is different with the two knives, but the Mule is thicker behind the edge.

[@quackocane]

When/if you press the edges together which edge bites into the other, would be a good test

[@J_Dukes]

Hey man watching this made me think of my zdp endura it didn't come very sharp from factory it's not easy to get a razors edge on I've seen you do it with very hard steels though.so my question is how much would you charge if you would do it at all to sharpen my zdp endura?there's another guy on KZbin smaller channel and he wants ridiculous amounts of money do it.thanks

[@michaelchristy4982]

John Dukes I don’t take sharpening jobs. Sorry man.

[@J_Dukes]

Michael Christy too bad thanks for the reply though

[@papyboyington4135]

Hello, I have a Spyderco Maxamet, it takes diamond or ceramic to sharpen it

[@yeaman992]

Time for the big guns!

[@michaelchristy4982]

Herb Toker you’re not joking.

[@Biketunerfy]

I noticed on one of your reviews on the jende products review you were looking for some kangaroo leather ?, I have loads spare so if you would like I can send you some, how does 4 square feet sound ?

[@michaelchristy4982]

stuart coyne email me. [e-mail]

[@Biketunerfy]

Hi there Michael. I’ve emailed you, did you receive it ?

[@michaelchristy4982]

stuart coyne got it and replied.

[@convex7456]

That's the knife steel you take on a deep space mission 🚀

[@andrewsandefur7715]

Something stood out, improper stones for the steel. Is this possibly how Rob, TheApostleP, came up with his results on Maxamet? Would the wrong stones cause the instability that he experienced?

[@michaelchristy4982]

Andrew Sandefur I was thinking that, but I talked with Rob about it and it seemed the stones he was using should have been fine. I don’t recall what stones he said they were, but I remember us talking about that aspect and that it shouldn’t have been an issue.

[@Jeffrose_]

I have a para 3 maxamet. I never use it so what I'm saying is I personally get to a point that the knife becomes to nice for me for everyday carry. May seem silly. I carry a para 3 lightweight in cts bd1n black. I'm not worried about using it.

[@michaelshults7675]

Spyderco ceramic will handle the carbides in Rex 121?

[@michaelchristy4982]

Michael Shults I would stick to diamond.

[@tinman1955]

Looks to me that the geometry of the two knives is different. I'm not sure how much difference that makes in this test but I suspect it may be significant.

[@Creelyblades]

Tin Man Edge geometry can certainly Have an effect, but keep in mind in this test both edges were at 30°. The thickness behind the edge and the primary bevel had different geometries, but those things should not affect the rate at which the apex of the cutting-edge dulls. The nature of this test really focuses only on the wear resistance of the apex. The test is only taken until the knife is no longer shaving Sharp, if the test were taken until the point it would no longer cut cardboard at all then the edge geometry would come into play.

[@TheFiendRacer]

Wow rex121 is amazing

[@AirborneSapper82]

Hi Michael. Do you sharpen knives as a business? I would very much like to send you my new Spyderco Maxamet for sharpening if you do. Please let me know. Thanks. I am a big fan of your work. Very impressive.

[@michaelchristy4982]

Armando Blanco I have been taking some jobs, but I’m taking several weeks off from sharpening jobs. You can reach out to Big Brown Bear for the Maxamet.

[@dfailsthemost]

Man, I feel like just polishing rex 121 would suck.

[@neroknives1828]

I think the price of them went way up now. I think they’re $350 now

[@michaelchristy4982]

Vinny Nero yeah, the knives in the Kickstarter were lower priced?

[@neroknives1828]

Michael Christy I believe so by a good amount. I can’t remember how much tho

[@neroknives1828]

Michael Christy you think it’s worth the $350? I’d just like to have some rex121

[@michaelchristy4982]

Vinny Nero if I wasn’t in on it in the beginning, I’d be willing to pay $350 for it. The knife is beautifully made, and I don’t think I’ve ever seen Rex 121 offered for the low of a price.

[@neroknives1828]

Michael Christy on kick starter $200 without a sheath, $250 with. He bumped it up to $350 I believe cause he needed more steel, after kick starter orders where completed. If the fit and finish is good $350 is still a good price. $250 is just crazy tho.

[@AGMartinez]

Get both knives corrosion-resistant coated

[@manifestgtr]

LOL 10,000” of cardboard. That’s about 1/6th of a mile for anyone keeping track...