Show Your Stoned Convexes!

[Jamesh Bond]

Ive been wanting to take this plunge. Curious lately how you freehand guys do your fully convexed blades, like Bark Rivers, on stones. Do you focus on the edge, or work the entire convex?

Plz share some pics and wisdom on this.

Thx.

 

[HeavyHanded]

Here's my trusty Bark River. Most of the time I use a Washboard with wet/dry, but the purists might not think that the same as a stone - though side by side it is very much in a range with my Nortons anyway. I still find these full convex and scandi do better with a softer stone than harder surfaces like diamond plates, though for this sort of work and on lower RC steels have had good luck dosing my diamond plates with a pinch of appropriate SiC dust and a few drops of water.

Used my Nortons with some extra mud, then reclaimed some to strop it up on WB. Resting on the 8k you can see some of the hatching around the curves. With careful work even this can be eliminated, or can be polished off on a hard strop etc (or ignored as it doesn't effect function one bit). Still had a bit of haze when finished. Normally I don't sweat the cosmetics much when using a stone on my convex, generally it transitions to a brighter finish over time anyway as it gets touched up. Was also in a hurry when I sharpened this - apologies for the poor pics.


Edit to add: I work the entire surface every time, even if its just a touch up on a hard strop - especially if its a touchup on a hard strop. I always beat on it extra good just behind the cutting edge - maintaining the apex nice and lean should never be a fight.

 

[Jason B.]

I found this old photo recently, old school Cold Steel Tanto with a shallow stone convex. Japanese natural stone around 10k, worked surprisingly well on the stainless steel.




Old draw knife



Final finish


BK2, finished on Shapton Pro 5k, smoothed with 2000 grit sandpaper, dipped in acid

 

[Jamesh Bond]

Noice.

Had a feeling I'd hear from you two lol.

How would a guy handle the upkeep when limited to a dual grit benchstone and ceramic rods in med and fine ?

Guessing use the stone to work the entire thing, but the ceramics on just the edge.

Am I warm ?

Thx.

 

[HeavyHanded]

With just that set-up is the only way to get it done. If the stone is silicon carbide and you use it with oil, as you finish with the fine side you can reclaim the grit on a sheet of paper and use it like a finer hone. Just wrap it around the coarse side of your stone. This will also blend any cosmetic issues very well. It makes a nice satin finish with a value somewhere around 800 grit or so.

Alternatively you can apply black and white compound to a sheet of paper and wrap that around the coarse side of the combi stone. Coming off the fine side, a one/two will bring the edge up nicely.

After that if you want to hit the apex with a few swipes on the ceramic, go for it.

https://www.youtube.com/watch?v=DF2Y7Hha0MQ

 

[Jamesh Bond]

Cool. Ive seen that vid several times. before thx to you. Always learn tons. Brilliant idea to use stone slurry to strop. I have been violently opposed to using oil for almost a decade. Actually spent an entire evening boiling my Crystolon In soapy water to remove it.

The first time i saw your vid, however, was the only time i ever had a second thought about going back. I might just get another one, but will likely just use the one i got. Should i resoak my stone or will that happen incidentally if i go back to oil ? Any oils to avoid or lust after ?

Thx.

 

[HeavyHanded]

If you use it with oil it will eventually load back up on its own. The coarse side might benefit from working in a film of petroleum jelly to hold oil on the surface. I boiled mine clean too when I first got it...

Regular pharmacy mineral oil works great. If you want to go back to water and not boil it a 2nd time, just use some dish soap in the mix. I've experimented with silicone oils and lamps oils, but they don't seem to offer much over the basic pharmacy mineral oil and are more of a challenge to manage.

Here's what I found - using with water the loose grit and abrasive sits on the surface more, the water helps keep it from embedding into the surface. Oil actually floats a much higher percentage of grit off the surface and I notice a finer edge. It also seems to promote faster mineral release and I notice less burr formation. As a plus it makes it easy to reclaim the grit too, perfect for the minimalist.

The reclaimed grit, while not the finest honing compound, works great as it retains a lot of sharp edges from being broken off the stone. Graded SiC at that size or smaller tends to be more jellybean shaped and not as aggressive without a lot of help.

I've used both and still do for convenience sometimes - my Norton puck gets used with water when I camp with it. If I have a choice I always use oil now. I also swear it keeps my finger sensitivity high compared to water - the skin doesn't absorb it anything like water, and once my finger pads are good and wet with water I have tougher time feeling burrs or lack thereof and 3 finger sticky.

 

[Jamesh Bond]

Cool. If I hear you correctly sounds like oil is the way to go.

Already have a buttload of mineral oil I bought to use on knife stuff.

Great minds lol.

Thx.

 

[Spyder59]

with just that set-up is the only way to get it done. If the stone is silicon carbide and you use it with oil, as you finish with the fine side you can reclaim the grit on a sheet of paper and use it like a finer hone. Just wrap it around the coarse side of your stone. This will also blend any cosmetic issues very well. It makes a nice satin finish with a value somewhere around 800 grit or so.

Alternatively you can apply black and white compound to a sheet of paper and wrap that around the coarse side of the combi stone. Coming off the fine side, a one/two will bring the edge up nicely.

After that if you want to hit the apex with a few swipes on the ceramic, go for it.

https://www.youtube.com/watch?v=df2y7hha0mq

nice!