Cleaning Rust Off a Dive Knife

[Green_Manelishi]

stainLESS means just that ... LESS, not FREE.

In order for stainless-steel to be "rust free" for any length
of time it must be HARD and that means it won't take an
edge easily so it is not ideal for a (dive) knife.

I use a high-carbon "stainLESS" blade and it rusts but it also
takes and holds an edge.

 

[The Hamburger]

GM,

I'm no expert , but..........


Wouldn't a "Hard" steel keep an edge longer than a "Soft" steel

and

Wouldn't a steel with a high carbon content be described as a hard steel.

I'm not making a point , this is just what I was led to believe. I could be wrong. (I was once, I think it was 1986 )

Cheers

 

[Green_Manelishi]

Well, I am no expert either but ...

Hard will hold an edge IF you can sharpen it (ceramic is a perfect
example of hard but difficult to sharpen)

Hard will not flex (it is more brittle .... relatively speaking) ... again
ceramic is a good example of hard and brittle.

Soft will take an edge but lose it quickly ... too soft will bend
too easily

I believe it is chromium, etc. that aid in the corrosion resistance
and add to the "hardness".

The goal is to find the best alloy for the intended application.
I prefer a bit less corrosion resistance and a better edge take
and hold.

ATS34, 55(?) and 440C are good quality stainless with nice edge holding ability but are rather high $$$ ... too high for me to use on a dive knife. I think OMS uses 440C on one of their knives.

The G-? and AUS-? used by SpyderCo and Cold-Steel take nice
edges but are not particularly corrosion resistant (in my experience particularly with the G-? that is used on my SpyderCo
"police" model)

 

[triggertravel]

Hamburger,

Thanks for the info! Do you put the clear varnish on the entire knife, including the sharp edge - or do you put it everywhere but the sharp edge?

Thanks!!

 

[The Hamburger]

TT,

Does'nt matter where you put the varnish.

Evene if you paint the edge as soon as you use the edge it will cut through the varnish.

I would stay away from the serated edge though.

This is only a good idea for knives that a rarely used.

Cheers

 

[The Hamburger]

As I understand it..........


ST37 is Mild steel or soft steel.

ST52 is High Tensile steel or Hard steel

The properties of ST52 come from it havoing a higher carbon content. The most utalized property of ST52 is that it is much more elastic than mild steel i.e. it will flex more and then return to shape.

When you say brittle do you mean more plastic (will bend but not return to shape) or is more likely to shatter under impact?

I believe that the European standards tend to increase the carbon content to reach these tensile strengths where as Japanese standards require the increase in Chromium content to reach the same levels of performance in certain areas.

Who is the NASA gadge he could explain / correct me I would guess.


I'm only repeating what I think I remember being talked about around me.

Cheers

 

[AndrewBlackburn]

Once cleaned (as much as possible), you could apply a thick coat of Vaseline to the knife. We find it works quite well - re-apply after use of course.

 

[Harvo]

spray it with WD-40

 

[FredT]

Coca Cola Classic

Just soak it a bit and the rust will dissolve.

FT

 

[Wreck Wench]

The Hamburger once bubbled...
TT,

Does'nt matter where you put the varnish.

Evene if you paint the edge as soon as you use the edge it will cut through the varnish.

I would stay away from the serated edge though.

This is only a good idea for knives that a rarely used.

Cheers

What constitutues rarely used? I'm guessing you mean a knife that is stored 'dry' until used. In my case, my knife is rarely used in the sense of taking it out and using it....but it rides on my inflator hose and therefore gets wet everytime I dive. Would the varnish help keep the rust at bay in this scenario as well? I'm ready to try anything.

Also for a quick cleaning trick I learned in the islands....use lemon and salt to make a paste and rub with papertowel....cleans up pretty quick and easily. I'm sure a brillo pad would have been easier!