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Knives for nets

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Magpie, what a star! well found, and thanks alexrom for pointing it out what a cool kit. maybe for my next knife... (nooooo..)
 
That's the kit. I have a rather excessive collection of knives and haven't found one yet that it can't get to a razor's edge. It also has super-fine diamond rods you can get on top of the two standard ones. But the standard rods work just fine for me.
 
It was good to see Ray Mears show how to properly sharpen a blade, although I was shocked to see how much cr@p he must carry with him when filming. He also did a good piece recently showing how to use a rock to sharpen a knife & sand & animal skin as sand paper to smooth hazel arrow shafts.

I like to sharpen my dive knife after every day trip & wouldn't have the time or patience for all that polava. I use a large mill b@stard file, which creates a sharp edge v. quickly. It creates an edge which is finely serrated that you can easily feel with the roughness on your thumb. I know offiencados will say that isn't as sharp as a smoothed edge but to me, it seems to cut better - like a cross between smooth edge & a serrated edge. I got the idea from ice climbing because it is good practice to keep you axes sharp (& usually custom re-shape them) - but not too sharp (or the edge can fold over) - and vital that you do not temper the blade & make it brittle; I sometimes carry a very small mill b@stard file on me to sharpen axes & crampons, esp. for multi-day trips. Simple, small & v. quick.

For other knives I use inexpensive dry stones (I have one that belonged to my grandfather & father). I have very coarse - for axes & bill hooks, medium (knives) & fine (for pen knives) For the filleting knive I use a v-notch kitchen sharper or fine stone & a butchers' iron to finish.

Sharpening serrations is a problem. I generally just grind the bevel. Sometimes I will use a round file to get it. I have a chainsaw-sharpening file which is often recommended for sharpening the teeth of ice axes, which could be used for bigger serrations I suppose.
 
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OOO Mr. X I had to cringe a little to hear you talk about how you like burred edges on your knives. But hey, to each his own. If they work well for you then that's all that matters. My mother used Ginsu kitchen knifes for years (have very fine serrations which basically don't get dull because they were never truly sharp to begin with) but she loved them. Of course I had to get used to eating my turkey with a spoon because the knives shredded it to bits, but I doubt that divers are worried about messing up a fisherman's net when they're trying to cut their way out of it. Just a note for you though. A burred edge or serrated edge works well when you can't get long and clean slices of the knife blade across whatever you're trying to cut, but you are applying a lot of pressure. They also work well for thing with tough exteriors and soft interiors (like many braided lines). A combo edge knife (with a serrated bottom and straight top end of the blade) works especially well for cutting through tough braided line (which serrated edges work best on) but also cutting through thick or thin plastic mono (which a serrated or burred edge knife can sometimes fail to work well on because the burrs get stuck on the mono). If you haven't tried a combo edge knife you probably should; you may like it. Also, if you really like burred edges on your knives try leaving them in salt water for a few days (rust creates great burrs and notches in the blades) Just poking a little fun; I think I've been a member long enough now to tease the veterans a bit.
 
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My knife does have a separate serrated edge. The "serrations" I mention from file sharpening are not visible, it's just that you will feel the edge if you run it across the texture of your thumb. That's how I check that it is sharp enough. I know that if you grind a blade very carefully (e.g. the 3 or 4 step process shown in the earlier video) that test will likely not work. I did try finishing the edge with a butcher's iron but it then failed the thumb tip test and I no longer felt confident in the edge. I sometimes finish off with a fine stone but again it risks failing the thumb test -- do you have a better sharpness test? I probably should mention that my knife has an unusual diamond cross-section, being a fish dagger so, for example, the highly rated Lasky system does not work with it (at least the owner & I could not figure out a way).

Oh found this paper test:
My dive knife is a work tool. I think of it like an ice axe or rip hook. I sharpen it, test it & oil it often but quickly. Admittedly, filing does not give a fine finish, my blade is scratched up. But, if it took longer, I would sharpen it less often, which could be dangerous. It doesn't rust because it is oiled after each sharpening; it is also made of shiney stainless steel, although not all oriental stainless is really stainless/rustproof. A material science student once told me the polished finish of stainless steel is an important aspect of its corrosion resistance (I thought it was the chrome content). I know they say a carefully sharpened blade lasts longer but my personal experience tells me that a frequently sharpened blade is reliably sharp; actually, the earlier video points contradicts Ray Mear's assertion that a sharper edge will last longer, it points out that a narrower, sharper edge will not last as long. I do have other knives that I sharpen more carefully and less frequently but they are specialised and aren't used anywhere near as much.

Only a veteran in the age sense! I'm keen to learn how to do these things better - feel free to make helpful suggestions. We've lost a lot expertise with guns & knives in this country which are alive and being actively used & improved in the US.

I've seen a few interesting sharpening gizmo's:
- an low speed electric kitchen knife sharpener with two grooves (coarse & fine or regular/fillet angle?) about £35
- a grinding wheel with rubber guide flange for use with a drill. Use for knives & garden tools. £12 or £15 with vice clamp for drill.
- colour coded, graded diamond covered "stones" - I would think these are quite good. Prices varied widely.
- a handle or wall mounted kitchen sharpening with 6 of 8 intertwined metal wheels on two axles. Works surprisingly well.
- plastic handle with mini-stone v-notch for sharpening kitchen knives - very common these days £1-£2.
- sharpening sheath. Used to have a wall mounted kitchen knife that sharpens whenever you draw it - always very sharp. Some fishing/filleting knives are currently being offered with this - good idea.

Great intro here:
 
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I've been lucky enough to have tried just about every sharpening system out there. Each has their place, some belong in the bin that's for sure. What I use is a wet grinder and Japanese water stones like Ray Mears. If you do sharpen tools on a regular basis then that grinder is a good investment
 
That really is mutts nuts of sharpeners Pastor. Are you a wood carver/knife maker/tool maker/cobbler/perfectionist/... or is it cheaper than it looks?

The sharpening guide was interesting. I read an article some time ago where the guy had carved a simple wooden edge guide that he clamped onto knife blades when sharpening on a regular stone.
This is interesting make your own knife. He used an oiled stone for sharpening too
 
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Arkansas stones are natural stones and are very very hard. Wonderful things but you need oil as a lubricant which gets on everything and unless you use a lot of oil they can clog up. Your every day double sided thing is made from silicon carbide which is very good but what is bad is the binding agent, it just doesn't hold very well so they tend to hollow easily (don't clog up) but are a complete b@st@rd to flatten again. Coupled with then needing oil makes then ideal for the bin. The japanese stones are made from carefully graded aluminium oxide (I think), very soft but easily flattened back to true. What I really like about them is that they are very fast cutting and use water as a lubricant which won't hurt anything. They are available in very fine grits too > 8000, I just use a 1000 and a 6000 along with the wet grinder for the heavier work when needed. Don't be fooled by the apparent fine sounding grit, they cut far far faster than any other stone bar the diamond stones. The diamond stones too are awesome but don't have the equivalent fine grades as water stones but they will stay very flat (which may be a slight disadvantage for some), They also need careful drying after use as the diamond is bedded into steel which can rust if you neglect them, the big drawback is the cost.

Those particular grinders are worth every penny, not only do they wet grind (cool, doesn't draw the temper) they also can be used as a hone with the supplied leather wheel which along with a fine cutting compound can create a mirror finished edge which is perfect for the likes of wood carvers and turners as well as for the majority of home applications including your dive knife I guess. APTC sell them and all the kit to go with them, mine is ancient now, one of the first ones.
 
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Wow! Nice stuff,I have discovered a small independent hardware store that sells an assortment of small machinist files such as triangle, square,and half round. These can be used to fit into the serrations of many knives. Hey Alexron, is that Benchmade knife "ATS34" steel? I love the expression 'knife junkie' and with an excessive knife collection !! Man, I'm Home :wave
 
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Very cool Pastor. I was about to post this link: Japanese Waterstones - Their uses and care but you already said explained it better.

Using a leather strop (bit long - but all you'd ever want to know and more!):
 
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Slingshaft: As I said "excessive" knife collection. The benchmade is a new type of steel (well new as of a few years ago) it is called H20 Steel. Specifically made for the water and will never rust (supposedly). But to its credit I've heard positive reviews (never used mine so I have no personal experience to go from). I did drop a Benchmade 940ti limited edition (about $400+ value) off of my boat in Rhode Island in December at about 9:30 at night (literally as I was getting off the boat to go out on a date) so I had to wait till morning. 17 feet of water, 36 degree temperature, and did not own a wetsuit at the time. So I erected a net with a boat pole taped and clamped to it. Got it out of the water the next day and cleaned it off. It's a titanium knife so the titanium components were perfect (titanium will never rust). The blade of the knife which is S30v (AMAZING STEEL...Highly Recommend) was perfect. And this is a steel which Benchmade doesn't describe as rust resistant...so I imagine their H2O steel must be quite good. Although the real test would be to leave it out in the air after being submerged, but I never do that with my dive knives anyway.

Mr. X: Interesting "knife" you use. Tool steels are not made with a mixture of alloys that are intended to keep a fine edge. This is why you have to resharpen it all the time. Basically steel can go two ways (brittle but really really sharp) or (really strong but not very sharp). Really brittle steel has an extremely high carbon content (like surgeons scalpels). It will also have a higher rating on the rockwell scale. But these steels rust really easily and are brittle (snap easily) so they are not good for tools or work knives. I have a carbon 5 fillet knife, the blade is coated in a some sort of compound all except for the edge. I washed it one day and didn't dry it until about 5 or 10 minutes later and it already started to rust.
The other type of knives are strong but the steel cannot be honed down to a really fine edge. These knives have high chromium content. And a lower rating on the rockwell scale. You are absolutely correct that the chromium is what keeps them rust free. A polished edge will prevent pitting and rust as well, but it is really the chromium which is the important factor.
What knife junkies like me do is check up on all the newest steel mixtures coming out (S30v, D2, ATS 34, 154CM, AUS 8, VG10, etc.....). Each of these mixes has some positive components and some negatives. Some of the newer steels are really quite amazing because they have the strengths of both sides but they are a little pricey. They are also not used in dive knives because the cost would be ridiculous and there is not really a high priced market for them.
Just curious, what is it about the ice axe that you like so much? It seems like it would be easier to just buy a knife rather than using that. By the way. With the type of steel the axe is made of, a sharper edge will get dull quicker (because its rockwell rating is probably rather low), and since you can't keep a fine edge on it a more "serrations" like the ones you mentioned will work better (because they will rip rather than cut).
As for sharpening tests, the thumb test is probably best for the type of edge you have on that tool. For regular knives the paper test is good but it dulls the blade (surprisingly paper will dull a blade much faster than cutting tougher materials). For a fine edge try placing the blade on a finger nail so it's completely 90 degrees and try to gently slide it across the nail (like you would on a sharpening stone (except for the 90 degree part)) If the knife slides it is too dull...if it sticks in the nail so it won't move that way then it is sharp enough.


On the subject of stones. Have any of you tried ceramic stones. They don't need to be oiled or watered (just cleaned occasionally). and they're extremely hard. They are brittle though and they will break if you drop them...but they work well for me. Just curious why no one has mentioned them here.
 
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alexrom1207 said:
...Mr. X: Interesting "knife" you use. .... This is why you have to resharpen it all the time. .
Click to expand...
Oh, it's a real knife, no need to quote it. Killed & gutted a lot of fish, cut a lot fishing line, even stabbed myself good with it:crutch. You misunderstand me re. sharpening. I don't resharpen it because it has dulled, it's never dull. I sharpen it because I want to be sure that it is always sharp when drawn. I would do the same with any dive knife no matter what wizzo secret ingredients the alloy might have. It is one of the cheapest knives I have but also the most used (and most likely to be lost) and I rather like it.

As I said, I already have a knife. I used to ice climb and your life is completely dependent on your axes and crampon front points, to a ridiculous degree really. However, the aim was not to achieve razor sharpness, as that would dull too quickly or, worse yet, fold over. There is a temptation to use a powered grinder (like the knife builder use on the video above) but it is important not make the steel brittle, so only hand tools are recommended for shaping & sharpening. I think of a dive knife as being somewhat similar, although it won't get used as harshly, it sees a lot of use killing & cleaning fish and cutting line, but its ability to cut might one day be of critical importance. However, I don't need to fillet with it. Using a mill b@stard file is the normal tool used & recommended for ice tools. I was pleasantly surprised by how quickly you put a very sharp edge on almost anything. I now keep a file by my large cleaning sink - so at the end of a long day, after cleaning fish & dive gear, I can sharpen my knife & spear with a few strokes before oiling & tidying them away. Although there will always be some new wizzo alloy, its hard to beat having a freshly sharpened edge. I'm not saying it is the best method, just that it works for me. Being carried & used in the sea, limits the applicability of many alloys -- although I have wondered if anybody uses non-stainless, non-titanium knives regularly in the sea? Would regular oiling/greasing provide sufficient protection?

Will try the fingernail test, thanks
 
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If you are serious about a knife for net,rope and wire that doesn`t need sharpening then there really is only one on the market at the moment and the rest are imposters /for posing. It is the "green river" utility knife originally from New Zealand for the kitchen/bread etc. It is now also produced by Hydrospace and called the "Backstabber" . It started off at a reasonable price of about NZ$8 to NZ$12 but since the demand went stupid and they realised that the folk that wanted them usually had a bit of cash the price is now extortionate. They even make a sheath for them now.
What use is a knife that gets blunt half way through a cut? (and usually with a finite air supply in the sport world) if you were fouled. Who carries sharpening gear down with them?
99.9% of so called "diving" knives are a complete waste of time unless you want a lever, something to stab with or pose. There are better tools for those tasks(including posing!)

This is what they look like...anything else is generally a joke and so is the owner....there gloves off!!rofl
 
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I had a Kai whetstone once. I believe it was ceramic. Really pleasant to use. Lost it, so am now looking at DMT sharpeners.
 
That's telling it straight! I notice Spearo Dave sometimes recommends kitchen knives too, Kitchen Devils. So, Mum's bread knife it is! Cut short by the looks of it. Reckon you'd need a second knife or iki-spike for finishing off fish though (unless you plan to saw them to death).
 
The kitchen devil that was in fashion for years was the little(about 4 inch blade) one with tiny serrations .They are lethal on rope/net and if you miss and slice yourself but then so is the Backstabber and it lasts forever. Some folk still carry them but only if they can`t get hold of the other.

now advice on posing....
 
One important reason to prefer diving knives over knives intended for use in the home or kitchen is that diving knives (like hunting knives or just generally knives intended for tough use) have a solid piece of metal that runs the entire length from the tip to the butt of the knife. This makes the knife stronger in general and it also allows you to use it as a prying tool (if need be). Also, dive knives are made out of steel which is not flexible and will not bend, but if stressed too far will snap. Kitchen knives and domestic knives are made to bend and flex back into position, because there is no need for them to be very strong. Omega3, not to take anything away from that knife, as I'm sure it works just fine, but from the look of the knife I doubt that the blade runs the whole length of the knife. Also, the steel looks like it is a flexible (probably 410 stainless...maybe 420 stainless) which is not a working steel. Probably what you like the most is the serrations, which do work great on tough rope. But, if I'm going to bring one thing down with me when I dive, I want to be sure that it is something that can get me out of trouble in a worse case scenario...which may involve more than just cutting rope.
 
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