A dumb question from one of your Aussie correspondents about how to make sense of steel specs. <br>For example, the description of a Swedish knife goes thus: "VG-10 stainless steel, hardened to 59 HRC."<br>No doubt this is meaningful to an expert, but I claim no knowledge of steel qualities. Is there a knife experts out there to help me with the basic guidelines I should look for in choosing a knife for a maritime environment?<br>I realise this is a matter of horses for courses. My knife use is in seakayaking; so I would be looking at cutting a mixture of marine rope and line, and in extremis, possibly defending myself against shark attack. Are there standards of stainless steel used for divers knife manufacture? I already carry a Sypderco folding knife which is small enough to be attached permanently to my pfd, [ lifejacket ] and operated one handed, but am looking for a backup tool.<br>thanks guys 'n' gals. BTW I enjoyed the recent thread on survival knives, which got me thinking... cheers, <br>PeterR

Hi Peter! I won't go into great detail here, there is so much on the web you can go blind sorting through it. HRC refers to the Rockwell scale of hardness. 60 is about as hard as they come.There are many variables in knife manufacture; hardness, metallurgy, cold and heat treatment, sheer size and method of manufacture ( forged, cast, stock removal.) All can effect the quality plus or minus No, there is no standard for marine knives, or any other for that matter. A "marine steel"' is like the mythical surgical steel, there isn't any. Obviously you want a stain-or rust resistant knife, which is what stainless is-resistant. What is allowable under the new knife laws in OZ? The classic sheepsfoot was regulated onto ships to keep sailors from killing each other. Obviously this isn't very effective on great whites , but nothing less than a harpoon is. Are you allowed "bang sticks" over there ( a shotgun shell on a short baton?)

I don't know nothing about marine steel, but I ask you something that fits under the Knife Steel Quality <br>I remember that someone forges steel and makes his own knives here (Chris? Presumed? I can't remember who..) I'm very curiously about that and I want to know how you judge your steel quality..<br>And, of course, what you suggest me to do to initially approach with knives making?<br><br>thanks in advance,<br>Mac

MAC, the two forums; www.kniveforums.com and www.bladeforums.com are full of information. Also, my friend www.ragweedforge.com has extensive links to knifemaking and supply sources. With the abundance of readily available materials, a knifemaker hardly needs to approach a foundry! I know for instance the Kukhris of Nepal seem to have started out as Mercedes Benz leaf springs!

>>makes his own knives here (Chris? Presumed?)<<<br><br>Not I. I did try a few small ones, decades ago when I was into blacksmithing, but I was never impressed with my own efforts. They worked, and I got some differential tempers to work, but they were pretty spectacularly ugly. I never had enough patience with grinding, polishing and fitting... and my thoughts as to what makes a good knife have changed a great deal since those days. Any web search on "primitive" knives will turn up smiths with a lot more skill and talent that I ever came close to. You can't forge for long without wanting to give it a try, though.<br><br>I've worked with smiths who said that they could judge a carbon steel, or at least the amount of carbon, by the amount of sparking it does on a grinding wheel, and how much the spark paths branch. I doubt that you can judge modern knife steels that way, but you can use it to easily see the difference between high-carbon and mild steel, so it's at least useful if you're scavenging steel.<br><br>I have hand-forged stainless tool steel, and I don't recommend it. It requires a great deal more force than forging typical high-carbon steel.. conservatively, three times the hammer weight, and more heat. The stuff is tough and nasty to work, difficult to control properly. <br><br>Except for some 18th-Century reproductions that I've bought from the makers directly, I buy knives from the same places everyone else does.

As you suggested, there is a range of different stainless steels commonly used in knives. VG-10 is very highly regarded as being well into the "premium steel" range when it comes to edge-holding and toughness. It is used in a number of Spyderco models as well as others and makes a terrific general-use knife. It will rust in a salt-water environment.<br><br>In terms of relative stainlessnes, there is generally a trade-off where you lose a lot of hardness and edge-holding to get the best resistance from rust which is obviously a big concern around salt water. Dive knives are typically made from 420 stainless which is very corrosion-resistant, but does not hold an edge very well and would not make a really great knife under dry conditions.<br><br>You will need to decide if you want a knife that holds a great edge, but you need to put some effort into keeping it cleaned and oiled or otherwise coated to prevent rust. If so, your VG-10 knife would be great. If you just want something that will be a decent knife and you don't have to worry much about rust, go with any cheap stainless knife. They are normally made from 420 or similar (440A, AUS-6). They are typically very stainless and take a decent edge, but need frequent sharpening.<br><br>If it were me, I would lean toward the VG-10 if you are talking about kayaking trips that do not span multiple days. Then you can easily rinse and coat the blade at the end of the day and you should be fine. For multiple-day trips, it will be harder to maintain the knife, and you may be happier with another steel. <br>

Salt water environment. Although not technically "steel", the alloys, Stellite 6 and Talonite, far surpass any steel in corrosion resistance. Check out Knife forums.com and Bladeforums.com for extensive commentary and reviews on these alloys. They are quite expensive, but hold an edge exceedingly well. _________________________________________________ Proverbs 21:19