Small knife jig adapter for very small knives

[grepper]

Blade size: 5 mm x 35 mm.  A very small knife.

This is a crude of a proof of concept, made from cutting a small strip of metal from a can of Del Monte Cut Golden Wax Beans. I just bent the strip in half, slipped it over the tang of the blade and clamped in in the small knife jig.  Very sturdy.  Stronger than you would probably think.

Much to my surprise, it worked perfectly the first time, putting a 20 degree bevel on the tiny blade, without interference from the small knife jig. Clamping to the tang keeps the blade centered in the jig.  Only used for grinding with the wheel, but then, on very small knives that's what you do anyway.

I think about three sizes would handle all knives too small to fit in the standard jig. Obviously the design and construction material could stand some refinement.

Once made, it's slip it over the knife, clamp in jig. Done. (Bob's your uncle). You get all the advantages of using the small knife jig.

[Rob]

What I dont understand about pocket knives like that is why you dont just freehand them?  I appreciate free handing isn't easy due to it being difficult to avoid tipping the angle and ending up with a multi faceted bevel.  But of all the knives, small bladed ones offer the most control to avoid that happening.  Two fingers placed one at either end of the blade is enough to prevent it rocking given they're so short.

I wonder have you tried free handing it or jumped straight to the improvised jig?

Based on the unsteadiness of longer (chefs) knives I could understand some reticence to free handing, with those tiny blades though, it really isn't difficult and its worth persevering to develop the skill

[Herman Trivilino]

Nice jig, grepper.  I can't wait to try it out.

Rob, for me freehanding gives me inconsistent results.  I'm looking for something better.

[Rob]

I agree its dang hard to get a consistent bevel on a long chefs or cooks knife but I really can't see the problem with what we call pen knives. I mean half of them have their blade length only twice the width or so of the grindstone.  They're by far the easiest blade to control a consistent angle (grinding away from you)

I guess my point is that are people letting the fear of inconsistent bevel problems deter them from really developing the technique (when those problems are more justified on longer knives)

I'm sure as hell no expert and yet find it pretty simple to grind small knives. I do freehand long knives too and I'm not bad at them but controlling a single facet bevel on them is substantially more difficult

[grepper]

Rob,

Why not freehand?  I'm not afraid of it or anything, I'm not very good at it. I can get it sharp, I'm just very slow... Could I get better?  Sure!  Would it be cool to do well?  Absolutely! Could I relax and watch TV with my little stone and practice?  Yupper!  I'm in complete agreement with everything you said.

But... I just got a razor sharp edge very quickly with the T-7.  With a little knife it takes almost no time at all, just as if the small knife jig worked out of the box for tiny blades.

Am I an uncoordinated goof for not bothering to improve at free handing?  Uh. Huh.

Does the little jig add-on get tiny knives really sharp, really fast?  Yup. 

Herman,

I'd be interested in you input when and if you try one.  Next round I'm going to make a cutout where the spine meets the handle so that the add-on can sit perpendicular to the blade.  I'm sure there are lots of fun issues to find and resolve.

What was cool and promising about it was that a rather lame first attempt with a little chunk of bean can worked so well.

[grepper]

Herman,

Might save just a little messing around...

With this incarnation of the thing, having the knife handle rest against the jig is what gives the knife stability.  Not to say this couldn't be overcome with design/material, but the little bent piece of scrap metal cannot grip the tang enough to stop the knife from rocking.

What's most interesting about this is that there is really no additional setup time.  Just slip it over the blade and clamp it down.  Only a few seconds longer than just using the small knife jig.

[Herman Trivilino]

I agree its dang hard to get a consistent bevel on a long chefs or cooks knife but I really can't see the problem with what we call pen knives. I mean half of them have their blade length only twice the width or so of the grindstone.  They're by far the easiest blade to control a consistent angle (grinding away from you)

When I remove the knife from the grindstone to examine it, and then find that I have to return it to the grindstone for further grinding, I can't get the same angle as I had the first time.  That's my problem, inconsistency.

With a softer steel it's easier because I can grind until I see the bur begin to appear.  But with harder steels I can't do that because no bur ever appears.  And it can't be felt, either!

[grepper]

Bail on the burr!  Just keep turning the knife often keeping an even bevel.

[Herman Trivilino]

Until the knife blade has been ground to nothing?!

Seriously, how do you know when to stop grinding?

The nicest pocket knife I own is a Buck 066.  Bought it about 5 years ago, it has no nicks in it and it has never been sharpened.  It now needs to be sharpened and I want to do it by removing as little steel as possible.

I've carefully measured the edge angle to be 40º, thus the bevel angle is 20º.  I've also determined by careful measurements that the side of the blade makes an angle of 2º with the center line of the knife.  Therefore the bottom of the knife needs to make an angle of  18º with the surface of the grindstone.  That's the angle I set the platform on my newly invented jig.

[grepper]

Hopefully the knife will become sharp long before you turn it into a toothpick!

I'm no knife sharpening guru or anything, so I'm just guessing.  Does it not stand to reason that if you remove metal from one side at particular angle, and then do the same on the other side, that the knife will become sharp?  The scanning electon microcope tests that were linked to here a couple of times clearly show that a wire edge and burr forms probably long before you could see or feel it.  Therefore, shouldn't turning the knife often and removing material at the same angle cause a thin edge to form?  I've found that I can get a knife extremely sharp without ever even checking for a burr at all!  In fact, without even condsidering the burr.

I know a knife can be sharpened to a different bevel angle on each side, but during the sharpening process the different angles would have to be maintained each time the knife is turned. 

Here is something else that might be happening.  Image down at the edge, what happens if the knife were rocking from side to side whilst sharpening one side.  If the rocking towards the edge always stopped in _exactly_ the same place, it would form a nice convex bevel.  But it it went over center, even just a little, it would destroy the edge each time, almost as if you were trying to produce a butter knife.  In this case the flipping and grinding would maintain a nice, dull edge, until the knife simply vanished.

Here's another way to think about it.  Let's say you take one pass on one side and form an edge at some angle.  If on the next pass, the blade is rocked so that it becomes more perperdicular to the wheel, a new edge would be formed at a sllightly different angle.  Back and forth, back and forth, each pass forming a new edge at a slightly different angle.  If the knife were rocked the other direction so that the edge was not contacting the wheel, then it would just be forming a secodary bevel.

I'm guesing here, but I suspect that if the knife is dissappearing and never getting sharp, that might be what is happening?  Does that make sense to you too?  Also, on tiny blades, it does not take much time or pressure!

BTW, that little jig add-on thing, got that little blade scary, razor sharp, very quickly.

[Herman Trivilino]

Does it not stand to reason that if you remove metal from one side at particular angle, and then do the same on the other side, that the knife will become sharp? 

Yes, but that occurs when those two angled surfaces meet.  I'm trying to find a method to tell when that happens.  I guess that if you can't see or feel the bur you just have to keep a close eye on those two bevels.  If bevel A is wider than bevel B, and then you flip and grind on bevel B until it's the same width as bevel A I guess that's when you know you're there.

Here's another way to think about it.  Let's say you take one pass on one side and form an edge at some angle.  If on the next pass, the blade is rocked so that it becomes more perpendicular to the wheel, a new edge would be formed at a sllightly different angle.  Back and forth, back and forth, each pass forming a new edge at a slightly different angle.  If the knife were rocked the other direction so that the edge was not contacting the wheel, then it would just be forming a secondary bevel.

I'm guessing here, but I suspect that if the knife is disappearing and never getting sharp, that might be what is happening?  Does that make sense to you too?  Also, on tiny blades, it does not take much time or pressure!

Yes, that makes perfect sense and may explain why freehanding doesn't work so well for me.

[grepper]

"Yes, but that occurs when those two angled surfaces meet. "

No doubt about that!

"I'm trying to find a method to tell when that happens. "

What if, for arguments sake, you couldn't tell?  If you just blindly, gently sharpened each side equally, the two angled surfaces would eventually meet and suddenly the knife becomes sharp regardless of how well informed you are of what's going on right at the edge.

That's what I do a lot of the time.  I check for sharpness often.  Oddly, it suddenly becomes sharp.  That's when I know to really take it very easily, with very little pressure, being careful to not muck up the edge.  Almost just a polish before a quick, light hone.

I've probably never got the two bevel angles exactly, precisely  the same, down the micron level, but I'm not sure that matters.  It's still really close, and gets _very_ sharp.

BTW.  What a beautiful Old Timer you have there.  What fine, worn, earthy patina.  I just want to hold it in my hand.  (And sharpen it )

[Herman Trivilino]

BTW.  What a beautiful Old Timer you have there.  What fine, worn, earthy patina.  I just want to hold it in my hand.  (And sharpen it )

Notice how much of the blades have been worn away.  I have this "eraser" that I rub over the blades to clean them up and give them a shine.

[Elden]

Neat idea, Mark. Was any deflection of the blade noticeable?

[grepper]

Hi There Elden,

Sorry, but I'm not sure what you are asking.