How long to reprofile?

[yepimonfire]

Been grinding away at a sog jungle primitive, set the angle from 30 to 20 degree per side. 1000 swipes on the 220 stone and its still not entirely apexed. Blade is made of 8cr, which despite everyone's comments, every knife I've had in it is hard to sharpen (for a non super steel).

 

[killgar]

Reprofiling can take some time. I once spent two full days reprofiling a fixed-blade made of very hard D2, and I was using an extra-coarse diamond hone. Of course I needed to remove a lot of metal. On hard steel I wouldn't use anything other than an extra-coarse diamond hone for reprofiling. When it comes to removing a lot of steel, it's the best tool for the job in my opinion.

The finer the hone, the longer it will take.

 

[Kai Winters]

Depends on the steel and the stone.
A coarse diamond stone/hone will take less time than a natural stone but you will have more scratches to remove.
I use a coarse diamond hone to start the reprofile process and it takes a bit over an hour on a 3.25 blade...to bring it to a hair shaving, polished finish.
The steel is Elmax...less hard steels take a bit less time.

 

[jobasha11]

Try doing one side first until it forms a burr on the other side. This will help you maintain your angle more accurately if you dont have a good "feel for it yet.

 

[David Martin]

A Norton coarse SiC stone is also a good one to use and far more economical than a X coarse diamond to purchase. DM

 

[Obsessed with Edges]

Been grinding away at a sog jungle primitive, set the angle from 30 to 20 degree per side. 1000 swipes on the 220 stone and its still not entirely apexed. Blade is made of 8cr, which despite everyone's comments, every knife I've had in it is hard to sharpen (for a non super steel).

The steel itself (8Cr) is easy to grind; the big/thick blade is what's making it take a while*. Taking 10° off each side means a TON of steel has to come off, on such a large blade. No matter the steel, that'll always take a while, unless using a powered grinder. If you're not wetting/oiling your stone, it might be a good idea to do so, to keep all that swarf clear while grinding. That much swarf could clog a stone pretty fast, which slows progress even more.

(* = assuming your SOG Jungle Primitive is the 9.5" blade, as described on a vendor site I'm looking at)


David

 

[Bill DeShivs]

Use a mill bastard file to set your initial bevels. It should take about 5 minutes.

 

[yepimonfire]

A Norton coarse SiC stone is also a good one to use and far more economical than a X coarse diamond to purchase. DM

Does it cut faster than a 220 waterstone? I know the grit is coarser but...

 

[Bill DeShivs]

Much faster.

 

[yepimonfire]

Okay I'll pick one up anyways I finally finished it at a total of about 1500 strokes. Usually I use my Smith's adjustable pull through sharpener. Has carbide blade which are usually awful for sharpening but it's excellent for reprofiling. Has angles in 2° increments from 14-24 and usually reprofiles a knife in about 30 swipes. Unfortunately the blades are worn and its been giving me uneven bevels.

 

[KennyB]

A bastard file will cut so much faster than a hone it can be easy to cause damage significant damage too, so be sure to use a light hand. Have you used a file before? I can give you some tips but I don't want to be presumptuous.

Usually it takes me a few hours to reprofile a blade on my 220 waterstone. It's a Norton as well. But it really depends on how much metal you're removing... Lowering to a more acute angle requires lots of stock removal, especially the thicker/longer the blade. The fastest I've reprofiled any edge is about 20 minutes, but that's from factory and I kept the factory angle--just evened out the bevel edges and stuff. The fastest I've done a serious change is an hour, and that was on a Swiss army knife. So yeah try to think of it in terms of how much material you have to remove when estimating how much time it will take.

My advice would be to just plan to take breaks when you make major headway. Otherwise you start getting anxious, like seeing the light at the end of the tunnel and trying to run faster to get there. Better to pace yourself because when you get tired--mentally and physically--you start making mistakes and ones that can basically undo your work, and leave you working longer.

 

[yepimonfire]

A bastard file will cut so much faster than a hone it can be easy to cause damage significant damage too, so be sure to use a light hand. Have you used a file before? I can give you some tips but I don't want to be presumptuous.

Usually it takes me a few hours to reprofile a blade on my 220 waterstone. It's a Norton as well. But it really depends on how much metal you're removing... Lowering to a more acute angle requires lots of stock removal, especially the thicker/longer the blade. The fastest I've reprofiled any edge is about 20 minutes, but that's from factory and I kept the factory angle--just evened out the bevel edges and stuff. The fastest I've done a serious change is an hour, and that was on a Swiss army knife. So yeah try to think of it in terms of how much material you have to remove when estimating how much time it will take.

My advice would be to just plan to take breaks when you make major headway. Otherwise you start getting anxious, like seeing the light at the end of the tunnel and trying to run faster to get there. Better to pace yourself because when you get tired--mentally and physically--you start making mistakes and ones that can basically undo your work, and leave you working longer.

I've used one to sharpen a machete, but on a knife I'm sure it'd be different because I would hold the machete by the handle with the tip pointing into a piece of wood, then slide it perpendicularly across the blade, works fine on a long 18" blade but smaller knives I'd have to do a bit differently. I'm sure if I had a vise it'd be no problem. How does a KO work sharp do in this regard? I've been considering on for this purpose.