What Are the Pros/Cons for Rex and Maxamet?

[marshmallow]

I noticed Rex and Maxamet steel knives are highly coveted. Which situations are both used for and are both different from each other? I have done a lot of forum reading and still cannot gauge how they differ from each other? I do know that they aren’t stainless.

[VooDooChild]

Both are not stainless.
Both have very high hardness.
Maxamet should have more wear resistance, should hold an edge longer.
Rex 45 should take more lateral stress across the whole blade.
I might think that rex 45 would have higher edge stability but that might depend more on what your doing to that edge and less on the "numbers".

[SubMicron]

I agree with VooDooChild and I use both steels at work, both on a Native 5 LW.

The high hardness for both provides strength at the apex. For me this means when I go home, my knife doesn't have reflective spots on the edge or spots that can be felt with a fingernail. The benefits are more clean cutting without binding, substantially less work sharpening, which then means that I wont use up the knife as fast.

REX-45 overall would be more durable than Maxamet. It's able to compete with CPM-M4 for durability and in some ways beats it.

Maxamet will have superior wear resistance and will be able to hold a working edge longer.

[208 tim]

Rex 45 seems to be less expensive than maxamet, but isn't a regular production steel. Yet, it comes close in performance. Maxamet also appears to be hard to obtain currently, but is regular production. :confused:

[The Meat man]

Maxamet is run harder and has almost 3 times as much carbide as CPM REX 45.

CPM REX 45:

1. 65 - 67 RC (Spyderco's HT)
2. Around 8% carbide volume

Maxamet:

1. 67 - 69 RC (Spyderco's HT)
2. Around 22% carbide volume

Maxamet gives you much higher wear resistance at the expense of some edge stability (though it's still really strong); CPM REX 45, with its lower carbide volume, will give you very high edge strength at the expense of raw wear resistance.

Maxamet will out-cut CPM REX 45, but REX 45 will be more forgiving if you accidentally torque the edge or something.

I have found that they both sharpen quite easily, using good quality diamond abrasives. I use a guided sharpening system.

They both seem pretty similar to me regarding corrosion resistance. If I had to give one an edge (punny!) I'd say the REX 45 might be slightly better than Maxamet in this respect.

[TomAiello]

If you want the longest lasting edge, Maxamet is the way to go. Nothing else in current production knives (from any manufacturer) really comes close.

Rex 45 (aside, 'Rex' is a poor description--when I first read this post I thought it was a discussion of Rex 121 v Maxamet) won't hold an edge as long as Maxamet, but generally has more edge stability (meaning it is more resistant to damage).

It seems like you have a lot of questions about steel, but maybe you need to resolve your questions into more precise terms.

Wear resistance, toughness and corrosion resistance are all different qualities of blade steel, and can vary widely for different steels. The steel with the best wear resistance is often not going to be the toughest (and vice versa). By spending more money, you can improve all three qualities, but at the top end, there is no "magic" steel that wins in all three categories.

For a folding knife where corrosion resistance isn't an issue, it's hard to beat Maxamet for long term edge holding (it will stay sharp the longest, basically). If you're just looking for the knife that will stay sharp longest, buy yourself a Maxamet Native or Manix 2 and be happy.

If you're going to pry or torque on the blade (cutting hard things like staples, twisting to break things like zip ties, or cutting through things with hard chunks like asphalt roofing tiles), I'd go with something tougher. If that's what you're looking for, you'll be happier with Rex-45 than Maxamet, but personally I'd go with something even tougher for those kind of tasks. If you still want good edge holding, then look at 4v, Cruwear or even 3v (in order from best edge holding/least toughness to best toughness/least edge holding).

If you want super stainless and long term edge holding, but aren't worried about toughness, then look at s110v. If you still want stainless, but are willing to forgo a little of the edge holding for more toughness, look at s90v.

In terms of regular production knives (so you're not chasing sprints and exclusives) I'd recommend you look at either Maxamet (stays sharp forever but not stainless) or s110v (stays sharp half of forever and is super stainless).

The only reason to venture beyond these for an average user is a requirement for increased toughness, in which case you're looking at sprint and exclusive (i.e. harder to find) knives. If you're going down that road, then Cruwear is likely to be the best balance of these properties for you, so maybe look at the upcoming Z-wear Shaman sprint (Z-wear and Cruwear are essentially the same steel). Or grab something in Rex-45 while they're still reasonably available, or maybe try K390 (the whole Seki family is upcoming in that steel, which has a nice balance of really long edge holding with a little more toughness than Maxamet).

[TomAiello]

Another thought: If you're not already familiar with it, have a look at this web site--it has a lot of good information about blade steels (and an accompanying smartphone app, if you're so inclined):

https://www.zknives.com/knives/steels/steelchart.php

[Karl_H]

I haven’t used Maxamet. That being said, Maxamet seems to be an extreme outlier material that is only a good option for hobbyists who are very careful with their knives and adept at sharpening. It is easy to break or chip a Maxamet knife.

Rex 45 is substantially tougher and a much better choice for people who don’t want to worry about accidentally breaking or chipping their knife. It will need sharpening more often, but will likely be much easier to sharpen.

[Albatross]

Rex 45 has phenomenal edge strength. It doesn't chip or roll nearly as easily as most other steels. Rex 45, due to its lower carbide content, offers a more refined apex, and using the 3 finger method, the edge can often feel smooth, unlike the rough feeling higher carbide steels like K390 or Maxamet. Rex works well for most cutting tasks, but if you're doing a lot of draw cuts, Maxamet or K390 would be better for that purpose. Those steels will simply cut better in that scenario.

Rex 45 has the added benefit of being able to handle very low angles at the apex. If you want to go below 15° per side, Rex is very happy to do so, which gives some nice performance. Maxamet can't be thinned out as much, simply because it's not as stable.

Rex 45 is more versatile, when it comes to edge finish. I've used 400 grit as a finishing stone, and I've used 1800. For strops, I've used 1 micron all the way to .25 micron and had no issues. I like a good polish for cutting leather or light plastics. The coarse edge works well for most other things. With higher carbide steels, you don't have as much wiggle room, you're kinda forced to go with a coarse finish.

I doubt either steel will disappoint.

[JMM]

If you want the longest lasting edge, Maxamet is the way to go. Nothing else in current production knives (from any manufacturer) really comes close.

Rex 45 (aside, 'Rex' is a poor description--when I first read this post I thought it was a discussion of Rex 121 v Maxamet) won't hold an edge as long as Maxamet, but generally has more edge stability (meaning it is more resistant to damage).

It seems like you have a lot of questions about steel, but maybe you need to resolve your questions into more precise terms.

Wear resistance, toughness and corrosion resistance are all different qualities of blade steel, and can vary widely for different steels. The steel with the best wear resistance is often not going to be the toughest (and vice versa). By spending more money, you can improve all three qualities, but at the top end, there is no "magic" steel that wins in all three categories.

For a folding knife where corrosion resistance isn't an issue, it's hard to beat Maxamet for long term edge holding (it will stay sharp the longest, basically). If you're just looking for the knife that will stay sharp longest, buy yourself a Maxamet Native or Manix 2 and be happy.

If you're going to pry or torque on the blade (cutting hard things like staples, twisting to break things like zip ties, or cutting through things with hard chunks like asphalt roofing tiles), I'd go with something tougher. If that's what you're looking for, you'll be happier with Rex-45 than Maxamet, but personally I'd go with something even tougher for those kind of tasks. If you still want good edge holding, then look at 4v, Cruwear or even 3v (in order from best edge holding/least toughness to best toughness/least edge holding).

If you want super stainless and long term edge holding, but aren't worried about toughness, then look at s110v. If you still want stainless, but are willing to forgo a little of the edge holding for more toughness, look at s90v.

In terms of regular production knives (so you're not chasing sprints and exclusives) I'd recommend you look at either Maxamet (stays sharp forever but not stainless) or s110v (stays sharp half of forever and is super stainless).

The only reason to venture beyond these for an average user is a requirement for increased toughness, in which case you're looking at sprint and exclusive (i.e. harder to find) knives. If you're going down that road, then Cruwear is likely to be the best balance of these properties for you, so maybe look at the upcoming Z-wear Shaman sprint (Z-wear and Cruwear are essentially the same steel). Or grab something in Rex-45 while they're still reasonably available, or maybe try K390 (the whole Seki family is upcoming in that steel, which has a nice balance of really long edge holding with a little more toughness than Maxamet).

[+1]

While this particular conversation always draws interesting comments, and tickles my tool-steel-funny-bone, which is 99% of my user Spydies, can I just say this post was very articulate & nicely done, bravo.

[sal]

Hi Karl_H,

welcome to our forum.

sal

[TomAiello]

I haven’t used Maxamet. That being said, Maxamet seems to be an extreme outlier material that is only a good option for hobbyists who are very careful with their knives and adept at sharpening. It is easy to break or chip a Maxamet knife.

Rex 45 is substantially tougher and a much better choice for people who don’t want to worry about accidentally breaking or chipping their knife. It will need sharpening more often, but will likely be much easier to sharpen.

I've definitely heard from reliable sources, and seen photos, of Maxamet being damaged. But I've EDC'd a Maxamet Manix 2 LW for at least a third of the days over the past 2 years and I have yet to damage it. On the other hand, I have chipped s110v (Manix LW) with exactly the same style of use.

I also think that factory sharpening is a good option for Maxamet. Most people on this forum are knife hobbyists, but most knife users aren't, and would prefer not to have to sharpen their knives at all. If that's your profile (not you, Karl, just in general), then buying Maxamet and sending it in for factory sharpening every few months is going to give you the utility of carrying a legitimately sharp knife for the minimum of cost and effort. If you enjoy knives as a hobby, that's not the case, of course.

Rex 45 still gives the average (non-hobbyist knife user) person a great, long lasting edge (just not as much as Maxamet) but I'd argue that for a non-knife person it's just as hard (i.e. feels impossible) to sharpen. I own and have sharpened (more than they need, I'm doing it for hobby value) both Maxamet and Rex 45, and I can tell the difference, but honestly I've never met a non-knife person who could tell the difference between them or sharpen either one. Most of my non-knife friends have trouble sharpening s30v, and I often sharpen s30v, s90v and 20cv for friends of mine (who I gave the knives to as gifts) who just aren't hobbyists and hence haven't put in the time to gain the sharpening skills necessary.

Fair point that Rex 45 is tougher--a non-knife person probably has a much greater chance of damaging a blade than even the most careless hobbyist.

[bbturbodad]

I'm not a "hard" knife user but I've never had any issues with Maxamet chipping or suffering any damage and the edge retention is second to nothing, absolutely in a league of it's own.

Here's a few videos of BBB running Maxamet through its paces...





A couple of my pics...

Just for fun I cut this can in half and then stabbed through it with no damage.



Here I cut several hundred feet of cardboard and it was still shaving cleanly.

[Naperville]

I like Rex 121 and Maxamet from a defensive weapons point of view. The best targets are relatively soft. The steels work for me.

If I had a Street Beat in Maxamet or Rex-121, you just have to know the targets and what it is good for.

[JohnDoe99]

I noticed Rex and Maxamet steel knives are highly coveted. Which situations are both used for and are both different from each other? I have done a lot of forum reading and still cannot gauge how they differ from each other? I do know that they aren’t stainless.

If S110V is any indication, they are probably extremely hard to sharpen. I can get S110V to shave hair from aluminum oxide (India stone) and ceramics fine, but still I don't feel like the retention is where it should be and that I am probably experiencing burnishing/weakening of the edge because the abrasive is having such a hard time cutting the steel, especially on the white/fine ceramic. Everything has an advantage and disadvantage. If you want the hardest possible steel, you have the pay the price of a very brittle edge and far longer sharpening times. S110V for example is "softer" than Maxamet and Rex 131, but even so, S110V on ceramic and aluminum oxide abrasives makes XHP or S30V look like 420HC.

For example, I am sharpening a native s110v right now for the first time with diamond coarse-extra fine DMT, after previously sharpening from the factory edge with ceramics, with very little pressure, and I can see the edge chipping under the microscope, and which chips noticeably worse after cutting through a small stack of print paper. Is that the burnt factory edge, or is it the inherent brittleness of s110v being exacerbated by the hyper aggressive cutting action of the diamond? Hard to say.

[RustyIron]

I have done a lot of forum reading and still cannot gauge how they differ from each other?

Maxamet is what I carry for work, and REX 45 is my weekend steel. While both are purportedly "super steel," you can't really abuse it any more than you can anything else.

My use can range from cutting wire in the vicinity of 18 gauge, reshaping plastic parts, shaving big copper contacts, cutting in half my Clif Bar if I'm only a little hungry (without even wiping off the blade), opening envelopes, jacking door locks, etc.

The edge retention on the Maxamet is really phenomenal for normal knife use. But if I'm jacking a difficult door or really hogging away at a copper contact, sometimes the edge becomes chipped to the point where I really need to sharpen it. But if I'm not stupid with it, then the edge will stay pretty sharp.

The REX 45 also has good retention. The gorgeous edge I put on it seems to degrade a little quicker, but the chippiness is less, so the edge stays usable longer.

My use of these materials is not always apples-to-apples, so these observations are more subjective than scientific. Overall, I prefer the REX 45, but carry the Maxamet more because the knife isn't my favorite and I don't care as much if it gets abused.

[Karl_H]

For those that have reprofiled the edges on their Maxamet or REX 45 blades, how thin have you been able to make the edge (without chipping or rolling during subsequent use)?

I am thinking less about the apex (which I cannot measure) and more about the grind angle and thickness behind the edge (which I can measure).

[marshmallow]

So basically Rex/Maxamet are super “tool” steels. They probably need good lubing once in awhile. I feel like they require more maintenance than say SV 30/90/110. Am I right?

[Snacktime]

I am a hard use knife owner... I don’t own maxamet but have a few Rex45 knives. Rex 45 is pretty nice with a paramilitary style thin grind, edge gets very sharp and holds an edge for general use. Rex 45 flat grind PM3 for cutting boxes is amazing. Rex 45 Shaman for scraping gaskets and cutting rubber belts (Kevlar) is not a good fit. Scraping and putting lateral force does causes chipping on Rex 45. I feel these super tools steels are not the best fit for hard use knifes that see prying and lateral pressure.

Tools steel is fragile, machine shop 101 for beginners.

[TomAiello]

So basically Rex/Maxamet are super “tool” steels. They probably need good lubing once in awhile. I feel like they require more maintenance than say SV 30/90/110. Am I right?

Yes. Because they are not stainless.

My recommendation is to use Tuf-Glide unless you plan to cut food with them. I prefer the Tuf-cloth applicator because it makes it super simple. I basically wipe them down at the end of the day.