Rex45=Hap40?

[Mordhaus]

So I was looking at the GPK page and in the product description for the manix 2 lw they put REX45 (Hitachi HAP40). I checked zknives to see if they crosslisted the two steels and they do, showing REX45 as a proprietary equivalent of HAP40.

Is this correct?

[Takuan]

According to Spyderco’s steel comparison chart ( https://www.spyderco.com/edge-u-cation/steel-chart/), they do seem to have very similar chemistry in terms of carbon, chromium, cobalt, molybdenum, tungsten, and vanadium. REX45 seems to have manganese, silicon, and sulfur, which are not included in HAP 40.

[Mordhaus]

According to Spyderco’s steel comparison chart ( https://www.spyderco.com/edge-u-cation/steel-chart/), they do seem to have very similar chemistry in terms of carbon, chromium, cobalt, molybdenum, tungsten, and vanadium. REX45 seems to have manganese, silicon, and sulfur, which are not included in HAP 40.

Thanks

[JuPaul]

As I understand it, yes, they are analog steels. However, the Japanese hap40 steel has always been clad on spyderco knives (wrapped in a layer of another steel, SUS410), and apparently run soften than the rex45 steel on Golden-made spyderco models. It's also my understanding that the cladding makes it impossible to test the hardness of the hap40 steel inside.

[Takuan]

Thanks

Sure thing. I’m really just biding time until Larrin can give you a proper response. :)

[Edited to account for posting delay: Julia’s response was very good. I didn’t want it to seem like I had overlooked it. :o}

[JMM]

AFAIK, depending on where/from whom you get your data, they are either identical or nearly identical in chemical composition. In the real world from my usage/testing Rex45 is a fair bit better in terms of edge retention & toughness, the more popular theory for this difference seems to be heat treatment, I'm not entirely sure that's entirely it, but I have been super mindful of sharpening both identically as possible and I would not say Hap40 is a steel I would seek out buying more of, Rex45 on the other hand, I have pretty much every model available (not the CS Para3 dual-scale coloured models) -- HTH

[Sharp Guy]

AFAIK, depending on where/from whom you get your data, they are either identical or nearly identical in chemical composition. In the real world from my usage/testing Rex45 is a fair bit better in terms of edge retention & toughness, the more popular theory for this difference seems to be heat treatment, I'm not entirely sure that's entirely it, but I have been super mindful of sharpening both identically as possible and I would not say Hap40 is a steel I would seek out buying more of, Rex45 on the other hand, I have pretty much every model available (not the CS Para3 dual-scale coloured models) -- HTH

Is there anything specific about HAP40 that makes it a no go for you? Or is it that you just find the extra performance of REX45 to be more ideal for your use? I have several knives with each and I've been very happy with both steels. I'm not the hardest knife user out there. Cut up a bunch of cardboard on garbage night or occaisionally at work, cut thick poly banding into small pieces once in awhile, maybe whittle on a hardwood block. That's about as hard use as it gets for me. So just about any steel seems to work well.

My guess is, if we had a blade of unclad HAP40 and the same blade in REX45 and both are heat treated to same harness using the same protocols they would perform virtually identical

[Wartstein]

AFAIK, depending on where/from whom you get your data, they are either identical or nearly identical in chemical composition. In the real world from my usage/testing Rex45 is a fair bit better in terms of edge retention & toughness, the more popular theory for this difference seems to be heat treatment, I'm not entirely sure that's entirely it, but I have been super mindful of sharpening both identically as possible and I would not say Hap40 is a steel I would seek out buying more of, Rex45 on the other hand, I have pretty much every model available (not the CS Para3 dual-scale coloured models) -- HTH

To be clear: I am not an expert at all, have only used HAP 40 (my favorite steel so far) and never REX 45, and only "know" what I read about the latter!

Still: You think REX 45 is superior in edge retention AND toughness?! The former seems plausible, given that it is run harder as far as I know, but I don´t see why is should be tougher (there may be reasons for that I am just not aware of of course)

Anyway: Spydercos HAP 40 is great steel in my use: Very good edge retention, still fairly quick and easy to touch up, I like the cladding with SUS410 from a historical but also functional point of view (makes the blade more corrosion resistent and presumably, well, "tougher"?) and I think cladded HAP 40 looks cool and gives each knife a very individual look (differently looking Patina on the HAP 40 part and differently looking "scratch pattern" on the very soft SUS 410 on each model)
Furthermore I personally had no rust problems with HAP 40, just forming of a nice Patina, despite using especially my HAP 40 Endura all the time and in any condition.

[Wartstein]

AFAIK, depending on where/from whom you get your data, they are either identical or nearly identical in chemical composition. In the real world from my usage/testing Rex45 is a fair bit better in terms of edge retention & toughness, the more popular theory for this difference seems to be heat treatment, I'm not entirely sure that's entirely it, but I have been super mindful of sharpening both identically as possible and I would not say Hap40 is a steel I would seek out buying more of, Rex45 on the other hand, I have pretty much every model available (not the CS Para3 dual-scale coloured models) -- HTH

Makes me really want to try REX 45... :) Given how great HAP 40 performs in my use, but in your experience REX 45 is even better. Maybe I should try to get that Manix 2 LW in REX 45 (since I guess it would be hard to find a REX 45 Millie for a reasonable price.. :rolleyes: )

[Mattysc42]

AFAIK, depending on where/from whom you get your data, they are either identical or nearly identical in chemical composition. In the real world from my usage/testing Rex45 is a fair bit better in terms of edge retention & toughness, the more popular theory for this difference seems to be heat treatment, I'm not entirely sure that's entirely it, but I have been super mindful of sharpening both identically as possible and I would not say Hap40 is a steel I would seek out buying more of, Rex45 on the other hand, I have pretty much every model available (not the CS Para3 dual-scale coloured models) -- HTH

To be clear: I am not an expert at all, have only used HAP 40 (my favorite steel so far) and never REX 45, and only "know" what I read about the latter!

Still: You think REX 45 is superior in edge retention AND toughness?! The former seems plausible, given that it is run harder as far as I know, but I don´t see why is should be tougher (there may be reasons for that I am just not aware of of course)

Anyway: Spydercos HAP 40 is great steel in my use: Very good edge retention, still fairly quick and easy to touch up, I like the cladding with SUS410 from a historical but also functional point of view (makes the blade more corrosion resistent and presumably, well, "tougher"?) and I think cladded HAP 40 looks cool and gives each knife a very individual look (differently looking Patina on the HAP 40 part and differently looking "scratch pattern" on the very soft SUS 410 on each model)
Furthermore I personally had no rust problems with HAP 40, just forming of a nice Patina, despite using especially my HAP 40 Endura all the time and in any condition.

Depends on how you define toughness. Rex45 is noticeably more resistant to edge rolling, and both are pretty difficult to chip, so rex45 is less likely to be damaged in normal use.

[Wartstein]

To be clear: I am not an expert at all, have only used HAP 40 (my favorite steel so far) and never REX 45, and only "know" what I read about the latter!

Still: You think REX 45 is superior in edge retention AND toughness?! The former seems plausible, given that it is run harder as far as I know, but I don´t see why is should be tougher (there may be reasons for that I am just not aware of of course)

......

Depends on how you define toughness. Rex45 is noticeably more resistant to edge rolling, and both are pretty difficult to chip, so rex45 is less likely to be damaged in normal use.

Thanks! But would that enhanced resistance to edge rolling not come for the price of being a tad more prone to chip? At least in "harder than "normal use""

[Albatross]

Thanks! But would that enhanced resistance to edge rolling not come for the price of being a tad more prone to chip? At least in "harder than "normal use""

Rex 45 is a steel that is one of the least likely to chip, and can attribute this to the higher hardness and the toughness it has. AKA edge stability. It's not ideal for users who like to pry with their knives, also because of the higher hardness. This is where the tradeoff is.

[Wartstein]

Thanks! But would that enhanced resistance to edge rolling not come for the price of being a tad more prone to chip? At least in "harder than "normal use""

Rex 45 is a steel that is one of the least likely to chip, and can attribute this to the higher hardness and the toughness it has. AKA edge stability. It's not ideal for users who like to pry with their knives, also because of the higher hardness. This is where the tradeoff is.

Thanks! :)

[Pancake]

Makes me really want to try REX 45... :) Given how great HAP 40 performs in my use, but in your experience REX 45 is even better. Maybe I should try to get that Manix 2 LW in REX 45 (since I guess it would be hard to find a REX 45 Millie for a reasonable price.. :rolleyes: )

Do it, buy it! I know you want to :D
If you end up not liking it, I buy it from you :D

[JuPaul]

AFAIK, depending on where/from whom you get your data, they are either identical or nearly identical in chemical composition. In the real world from my usage/testing Rex45 is a fair bit better in terms of edge retention & toughness, the more popular theory for this difference seems to be heat treatment, I'm not entirely sure that's entirely it, but I have been super mindful of sharpening both identically as possible and I would not say Hap40 is a steel I would seek out buying more of, Rex45 on the other hand, I have pretty much every model available (not the CS Para3 dual-scale coloured models) -- HTH

Makes me really want to try REX 45... :) Given how great HAP 40 performs in my use, but in your experience REX 45 is even better. Maybe I should try to get that Manix 2 LW in REX 45 (since I guess it would be hard to find a REX 45 Millie for a reasonable price.. :rolleyes: )

You know you should! Only 2 chances left for you to try it - the Manix lw or the Chief. You've been tempted since the first g10 manix came out...

But seriously, you have a ton of real-world experience with hap40, and I'd really like to see how rex45 compares in your opinion. For me the tradeoff is superior edge stability for ease in sharpening. I never had issues with hap40 rolling, but I've only used it on Delicas and Dragonflies, and I don't often use those knives for more punishing outdoor jobs (like you use your Endura). So far, rex45 seems excellent in those conditions, though. I'd love to hear what you think.

[Larrin]

According to Spyderco’s steel comparison chart ( https://www.spyderco.com/edge-u-cation/steel-chart/), they do seem to have very similar chemistry in terms of carbon, chromium, cobalt, molybdenum, tungsten, and vanadium. REX45 seems to have manganese, silicon, and sulfur, which are not included in HAP 40.

Mn and Si is in every knife steel so if they aren't listed it's just because the amounts aren't shown in the datasheet. Sulfur is usually not an intentional addition but an impurity, so some datasheets will list a maximum allowable amount.

[Albatross]

According to Spyderco’s steel comparison chart ( https://www.spyderco.com/edge-u-cation/steel-chart/), they do seem to have very similar chemistry in terms of carbon, chromium, cobalt, molybdenum, tungsten, and vanadium. REX45 seems to have manganese, silicon, and sulfur, which are not included in HAP 40.

Mn and Si is in every knife steel so if they aren't listed it's just because the amounts aren't shown in the datasheet. Sulfur is usually not an intentional addition but an impurity, so some datasheets will list a maximum allowable amount.

That's interesting. Is there an industry standard maximum allowance for sulfur content?

[Takuan]

Mn and Si is in every knife steel so if they aren't listed it's just because the amounts aren't shown in the datasheet. Sulfur is usually not an intentional addition but an impurity, so some datasheets will list a maximum allowable amount.

Thanks! So would you say the primary difference between REX 45 and HAP 40 is the heat treatment (if there are significant differences, that is)?

[Larrin]

Mn and Si is in every knife steel so if they aren't listed it's just because the amounts aren't shown in the datasheet. Sulfur is usually not an intentional addition but an impurity, so some datasheets will list a maximum allowable amount.

Thanks! So would you say the primary difference between REX 45 and HAP 40 is the heat treatment (if there are significant differences, that is)?

Yes they are the same steel, a very common PM high speed steel in Europe especially. The European designation is 1.3244. It’s sold under a lot of trade names like ASP2030, S590, and Vanadis 30.

[araneae]

According to Spyderco’s steel comparison chart ( https://www.spyderco.com/edge-u-cation/steel-chart/), they do seem to have very similar chemistry in terms of carbon, chromium, cobalt, molybdenum, tungsten, and vanadium. REX45 seems to have manganese, silicon, and sulfur, which are not included in HAP 40.

Mn and Si is in every knife steel so if they aren't listed it's just because the amounts aren't shown in the datasheet. Sulfur is usually not an intentional addition but an impurity, so some datasheets will list a maximum allowable amount.

That's interesting. Is there an industry standard maximum allowance for sulfur content?

My guess would be that the goal is as low as possible. My wife is in the Aluminum industry and they always have contaminants that are in the mix, but the goal usually is as little as possible.