H1 and Sharpmaker fine stones

[ric75]

Hi!

I had to resharpen my Dragonfly 2 Salt.

With diamond plate and Sharpmaker diamond stones i managed that. Felt a burr on both sides.

A little touch up with gray stones and it slices paper. Not perfect but for a user knife it is OK.

Whenever I use fine stones the edge feels immediately smooth and polished.

Its so slippery it glides off the paper.

No chance for a clean cut only sliding on the paper and not cutting.

With S30V or other steels i don't have that issue.

Am I doing something wrong, or is H1 here special?

Thanks, ric

 

[Obsessed with Edges]

I've heard/read that H1 is relatively soft/ductle, and won't necessarily take or hold a very fine/polished edge for long. H1 is a 'work-hardened' alloy (not heat-treated for hardening), with almost no carbon content in it. The near lack of carbon makes it more corrosion-resistant, essentially rustproof, or as close as it gets to being so. That's what H1 was made for.

Carbon content in a true 'steel' alloy makes other typical steel blades hardenable via heat treat, which then makes them better able to take & hold a more polished, stronger and more durable edge. The flipside is, higher carbon content in a steel knife blade also makes it more vulnerable to corrosion. So there's a trade-off between edge-holding and corrosion resistance, as the carbon content is varied or eliminated altogether.

A coarser finish would likely be more useful for it, to keep it 'utility sharp', but not necessarily hair-whittling.

 

[colubrid]

I've heard/read that H1 is relatively soft/ductle, and won't necessarily take or hold a very fine/polished edge for long. H1 is a 'work-hardened' alloy (not heat-treated for hardening), with essentially no carbon content in it. The lack of carbon makes it more corrosion-resistant, essentially rustproof, or as close as it gets to being so. That's what H1 was made for.

Carbon content in a true 'steel' alloy makes other typical steel blades hardenable via heat treat, which then makes them better able to take & hold a more polished, stronger and more durable edge. The flipside is, higher carbon content in a steel knife blade also makes it more vulnerable to corrosion. So there's a trade-off between edge-holding and corrosion resistance, as the carbon content is varied or eliminated altogether.

A coarser finish would likely be more useful for it, to keep it 'utility sharp', but not necessarily hair-whittling.

That is a great answer and explanation. Thanks you!

One question though. What is the difference between a "work hardened" steel vs a heat treated steel? I wlays hear these terms but don't know what that means.

 

[Obsessed with Edges]

That is a great answer and explanation. Thanks you!

One question though. What is the difference between a "work hardened" steel vs a heat treated steel? I wlays hear these terms but don't know what that means.

'Work hardening' generally refers to a hardening of the alloy by some mechanical means, like the vibration induced in powered grinding, or hammering, etc. In theory, it means H1 could be hardened pretty well by such means. In practice though, it seems like most attempts at it don't quite go so far, because, with powered grinding at least, the vibrations induced also come with the immediate removal (by grinding) of the surface metal being hardened in the process. So, any benefit of hardening is usually very thin at the surface and fleeting by it's nature.

Heat treat, as the name implies, hardens steel ('steel' = iron + carbon) at very high temperature, and it's hardened fully through the steel (usually). This means, even if steel is ground away afterward in shaping & sharpening, the remaining steel is still hard and strong.

 

[colubrid]

Why not heat treat a work hardened steel then? What I mean is if you heat up H1 will it effect it positively or negatively?



I guess I still don't understand the complexities. Just ignore my stupid questions. I will never understand.

 

[Obsessed with Edges]

Why not heat treat a work hardened steel then? What I mean is if you heat up H1 will it effect it positively or negatively?



I guess I still don't understand the complexities. Just ignore my stupid questions. I will never understand.

The sufficient carbon in true steel is what enables it to be hardened by heat treat. By 'sufficient', that usually means it needs at least 0.4% or higher of carbon, to get any significant hardening of steel. Think of a simple stainless, like 420, for something with the bare minimum of carbon available to harden it very much for edge-holding's sake.

If the carbon isn't there in enough quantity, as with H1 (0.15% carbon), the alloy wouldn't respond to heat treat anyway, which is why heat treat isn't done with H1.

 

[colubrid]

The sufficient carbon in true steel is what enables it to be hardened by heat treat. By 'sufficient', that usually means it needs at least 0.4% or higher of carbon, to get any significant hardening of steel.

If the carbon isn't there in enough quantity, as with H1 (0.15% carbon), the alloy wouldn't respond to heat treat anyway, which is why heat treat isn't done with H1.

Okay got it! Thanks for the great explanations.

So heating the H1 will not harm the steel at all? I can make it glowing hot and it will not hurt it or change anything?

 

[Obsessed with Edges]

Okay got it! Thanks for the great explanations.

So heating the H1 will not harm the steel at all? I can make it glowing hot and it will not hurt it or change anything?

I wouldn't assume that. Any metal has a melting point, at least. And I'd assume there's a point where too much heat would likely damage it, in some form, though I don't what that would be or how hot it'd have to get.

 

[ric75]

@obsessed-with-edges
Thanks for your answer.

I knew that H1 is softer but did not think of that behavior.

Now I understand more why H1 is better with serrations. Thinner blade and harder.

The cutting of the serrations hardens the steel im that area.

 

[me2]

H1 is hardened by cold rolling and hardens further during grinding of the bevels and edge on serrated versions. Strength induced via cold rolling/work hardening will be reversed and lost of heated too high. How much is too much depends on some specifics of the steel in question. H1 also has a fair bit of nitrogen, which behaves similarly to carbon.

 

[Carboniferous]

I think I read that the stock for H1s starts out at 7 mm and is rolled to final thickness to induce work hardening