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Panzer
08-17-2010, 11:56 AM
I must admit for all the crap I know how to do and all the skill I feel that I am good at knife sharpening has not been one of them. I have several systems on my work bench but none seem to do the trick or maybe it's just my technique.

I own a Sharpmaker, Falkniven DC4 and even a Tri-hone Arkansas stone system. The Sharpmaker seems to work the best but not for all blade styles. Which brings be to the point are some systems better for different blade styles.

I own Scandi and Convex. What to do?!

Draven
08-17-2010, 12:40 PM
I only have a couple convexed blades, and do all my sharpening on a foam mousemat with wet or dry sandpaper over it - then move onto the strop, which is a mousemat with thin leather (upholstery leather, flesh up) tacked over it. The strop has compound on it (just this red stuff that came with my dremel knockoff) and works a charm. The give in the mousemat really helps with doing convex edges, though you will often still need some "roll" in the movement of the blade to sharpen the whole grind, depending on just how convexed it is. Sharpening convex blades on a stone is an artform, I could probably maintain one for a while using a pocket stone but like hell could I keep it as new for longer than a few months of lots of cutting! With convex most people sharpen edge trailing (move backwards across the strop/paper rather as opposed to pushing the edge forwards) from what I hear, and that's how I do it too.

For scandis, I always give them a secondary microbevel unless they're dedicated carving knives. Sharpening the full grind is a VERY rare occurrence when sharpened with a microbevel, and it still cuts good with much better edge retention. The full grind doesn't need to be that polished either. I sharpen the flat grind edge-leading (like you're shaving the stone) until it's reasonably sharp, then move straight to 600 or 800 grit sandpaper on a mousemat (if I have the 800, I'll use it rather than the 600). You want to raise the spine a bit more (since you don't want to take away metal on the flats, just the edge) and lightly sharpen on the sandpaper hone as you would with a convex. It only takes a few passes per side, probably less than 10 altogether. A good microbevel should IMO be less than 1mm wide. Then strop again. Since it's only a tiny band of metal you're removing, it is exceptionally easy to give it a fine polish, meaning that the cutting edge is straighter, stronger and push cuts go much smoother. From this point on a strop is all you need until the microbevel gets too wide.


I hope that's clear and hope that's not more than you're interested in :D I have a love of knives, but I hate sharpening. Hate it with a passion. It's like polishing my boots, I do it whenever I need to and I do the best job I can but damned if I'm going to spend more time or money on it than is absolutely necessary. The stone I use for sharpening was £1 (aluminum oxide I think) and the paper is a ridiculous £4 a pack, the mouse mats were £1 each I think and the wood I glued them to was scrap. The leather was scrap too. I could try and get some pics if you want to try it my way but I didn't explain it good enough!

Pete

Trekon86
08-17-2010, 12:55 PM
For convex I like to use an old neoprene mousepad and some fine grit sandpaper.

For scandi I use a benchstone of some sort.


For scandis it helps to have the longest, widest stone you can afford.

I haven't had much luck with my waterstone. It wears too quickly to be cost effective, though it does put a nice edge on most knives.
PMZ

Sgt. Mac
08-17-2010, 12:55 PM
Here's a great vid Iz did on sharpening Convex blades, this is the way I do it nd have had excellent results



YouTube - Basic convex shaprening (http://www.youtube.com/watch?v=Rt44uDP82CE&playnext=1&videos=PUTh5RIKdbk)

Trekon86
08-17-2010, 12:56 PM
Yup that's a good video, thanks for posting it up Mac!
PMZ

justin_baker
08-17-2010, 01:08 PM
I think that you, along with many others, are putting too much thought into sharpening systems. Its all about keeping the knife at the right angle, doing that takes muscle memory and a bit of practice.

Im no sharpening master by any means, but i can get my knife sharp enough to do anything i want it to do out in the woods. I cant get it shaving sharp, its probably substandard for all the knife freaks out there, but it works fine for me. I sharpen out in the woods, freehanded as in holding it in my hand while sharpening in mid air. I make it a point to do it fast and only get a decent edge. I like to be time efficient with my sharpening so that i can get back to whatever i am doing as fast as possible. Getting a knife scary sharp takes way too long and you are just going to lose your super sharp edge fast if your batoning and carving up everything in sight. Thats why i spend a little time getting a decent edge instead of taking a long ass time to get a super sharp edge.

All i use is your regular double sided wetstone. Any sharpening stone from any hardware store or wherever you can buy one should work fine. Keep it simple, fancy diamond stones and compounds are not really necessary unless you are going to shave with your blade or you are working in a profession that requires a very sharp knife.

If you want to get your knives super sharp, by all means, aspire to be able to do that! But you need to lower your expectations at first. Start by getting an edge good enough to do feather sticks with ease. Once you are able to do that, then go for the next level of sharpness.

Try finding cheap dull knives and giving the best edge you can give them. Sharpen like 10 in a row. Your first knife that you sharpen will suck, but by the time you got through all 10, go back to the first one and resharpen. I have no doubt that your next sharpen will give it a much better edge than the crappy one you originally gave it. This is how you can get really good at knife sharpening.

Again, im not that great of a knife sharpener, but i sharpen my gear a lot at very efficient speeds in the field. I cant get a knife scary sharp because i usually dont have a need too. But with practice, you will be able to get a decent edge quite quickly.

Draven
08-17-2010, 01:08 PM
Thanks for posting that up Sgt :D Good vid!

I went to find a convex to try the technique out on but convex knives don't seem to know how to get blunt :confused: :D

drewhelean
08-18-2010, 09:52 AM
While I am still new to bushcraft I have to admit that sharpening a knife is more daunting to me than being lost in the woods. I bent and bought a Lansky Puck (to carry in my pack) based on recomendations but, I have never sharpenend a knife. I have watched videos on Youtube but, always fear that if I do it wrong I will either make the edge worse or make my knife completely useless... I need someone to come out and hold a clinic so that I can have someone check my form.

scoutsurvivor
08-18-2010, 09:58 AM
Practice, practice, practice, DW. Make plenty of mistakes. Jack up your edges. That's the only way any of us learned. I started on the road to learning how to sharpen knives many moons ago watching my pop sharpen his Old Timer pocket knife and have been sharpening my own knives ever since. I can get mine scary sharp if I want and I still screw it up every now and then. No such thing as an expert.

sp™ceghost
08-18-2010, 04:42 PM
The Scandi grind is straight forward, just use a flat stone and lay the bevel from edge to first angle, the sharpen like most knives. The convex: just get a leather strop, load it with GREEN stropping compound, and then stroke it AWAY from the edge. Get on youtube and search for it!

Scotsmanspride
08-18-2010, 04:45 PM
Scandi..... Get. Piece of glass from the hardware store at the size u want and tape or light water before you lay down wet/dry paper.....VOILA. Convex. Mentioned above with mousepad. Don't forget to strop afterwords. Some people like the sharp maker(sharp keeper) but I am going to sell mine soon. Keep the fallkniven for field work on scandi knives.

Phaedrus
08-19-2010, 04:59 AM
Sandpaper or 3M abrasive film if great for convexed edges. If you use a mousepad get the thinner, harder type designed for an optical mouse. You can put the abrasive on a notebook back, too- it has enough give to work. You don't want too much give; that will round your edge off.

I use synthetic waterstones for most of my sharpening. And DMT diamond Diasharps for the coarse stuff. True, they do dish but flattening is a pretty easy & quick affair. The nice thing is that you can grits as low as 24 or as high as 30,000+! We're talking roughly 1/4 micron, there- about bacteria sized.;)

A belt grinder is also handy, especially for convex. You can get a Harbor Freight 30" x 1" for about $30 shipped on sale. It's pretty easy to learn to use, too.

sp™ceghost
08-19-2010, 07:27 PM
Sandpaper or 3M abrasive film if great for convexed edges. If you use a mousepad get the thinner, harder type designed for an optical mouse. You can put the abrasive on a notebook back, too- it has enough give to work. You don't want too much give; that will round your edge off.

I use synthetic waterstones for most of my sharpening. And DMT diamond Diasharps for the coarse stuff. True, they do dish but flattening is a pretty easy & quick affair. The nice thing is that you can grits as low as 24 or as high as 30,000+! We're talking roughly 1/4 micron, there- about bacteria sized.;)

A belt grinder is also handy, especially for convex. You can get a Harbor Freight 30" x 1" for about $30 shipped on sale. It's pretty easy to learn to use, too.

The green compound that is used for stropping gets down to .5 micron... pretty crazy!

Phaedrus
08-19-2010, 10:40 PM
I have some 0.25 micron diamond spray and a sharpening lunatic friend of mine is sending me some 0.1 micron!:eek: I honestly have no idea what to even do with the latter. My first attempt will be to use it on a strip of balsa wood but the wood may not be smooth or flat enough. We'll see.