Ionut's Small Knife Jig

[ionut]

That looks great Herman, and it is much better using it against the blade, it is much easier to control. I am glad it works well for you.

Ionut

[grepper]

Hey Herman,

I wonder if you could drill just one hole through your metal plate, centered,  just behind the trailing edge, (away from the wheel), of the scissors jig tool rest, and then put a single screw down through the top of the plate just like the two screws you have now.

Then make a small metal bar with a hole in it towards one end that would slide up the screw and extend under the scissors jig tool rest on the other end.  You could then get a nice knob like you used to make the control bar micro adjuster, which would tighten, going up the screw, pressing the small bar against the bottom of the scissors tool rest, thereby clamping the metal plate to the scissors tool rest.

Then when you wanted to use it, there would be almost no setup time.  Just slide it on, clamp it down and Bob's.... (Doh!...  Rob!) your uncle.  No messing around with screws and nuts, and it would work with no modification to the scissors rest.

Does that description make sense?

Or maybe even, dare I say...,  two screws like you have now with a square metal plate with two knobs on the bottom.  That would allow you to push the two screws up against the trailing edge of the tool rest to help center it.

I have no idea if that could hold the plate tightly enough against the tool rest, or what other puzzlements might pop up during testing, but it was an idea that came to mind as I was admiring your version if Ionut's jig idea.

Or maybe even copy the fulcrum idea like the clamp on the small knife jig???

[Elden]

I can see how this jig may surpass the knife jig for sharpening all knives, not just small ones.  One advantage it has is that it keeps the bevel angle constant all the way to the knife tip.

I like this, Herman. It didn't register with the first reading.
This was what I was referring to in a different post in another thread. I personally like the bevel angle to be the same all the way to the point of the tip. Yes, the width of the bevel grind will become greater on the tip, but remember the tip as it goes out to the point, gets thicker. The width of the bevel will have to increase for the bevel angle to remain the same.

See:   http://forum.tormek.com/index.php?topic=1191.msg5104#msg5104

That's my preference and I know not everybody agrees. I still like my DMT Aligner for my own personal knives  because of that reason. But Herman's statement confirmed what I have wondered ever since reading Ionut's original small knife jig posting several weeks ago.

[grepper]

I wish you guys would have designed this before I sharpened my first machete.  It seems like it would have worked nicely for that, and for other very long blades for that matter.  Might have to remove the honing wheel.

[Elden]

Good thought, Mark. I had a young fellow at church, yesterday, ask me to sharpen a machete for him. Wasn't looking forward repositioning it in the knife jig. That or the tool rest would be the ticket.

[Ken S]

Elden,

Check out my SVD-45 jig described in my recent post.  It might be just the ticket for sharpening muchos machetes.

Ken

[Elden]

Ken,
Would you post a link to that, please?

[Ken S]

Elden,

I'm not too slick with links.  Here's a low tech copy paste:


Ken S
Hero Member

Posts: 559
 

inspired by Ionut and Herman
« on: Yesterday at 10:15:54 pm »
QuoteModify
Back during the time period when Ionut made his small knife blade jig, I posted a couple ideas.  One was for a wooden jig, similar to Ionut's.  The other was essentially sawing an SVD-110 in half.  That would allow a small blade to be held on either side of the wheel, as the table would be about the same width as the wheel.

I purchased a second SVD-110 at the time, and never got around to finish the jig. 

Herman inspired me with his jig.

this afternoon I got out the SVD-110s.  one had two holes for holding screws.  I measured off a line about 1 7/8" from one side and headed toward the bandsaw.  My 1/2" 3 tpi blade made short work of the cut through the extruded aluminum.  Surprisingly, the cut was almost as smooth as the factory cut.

I knew I would need to turn the jig around to get close enough to the wheel.  I had purchased a regular 6mm short bolt to substitute for the Tormek knob.

Alas, the bolt was still too long.  I ground down the bolt on the belt grinder.  Still too long.  I filed down the threaded surface on the jig.  Still too long.  At this point I am unable to get close enough for a 20 degree bevel.

I have not given up.  I will attach something, either wood or metal on top of the jig.  It will work in time.  For now, I have an SVD-110, an SVD-70 and an SVD-45.  (wow!)

still plugging along.....

Ken

[grepper]

Herman,

Another idea came to mind.  I have no clue if it's even needed or a good idea, but it's an idea nonetheless.

What if your top metal plate was wider than the wheel, so that, with a cutout in the center of the metal plate, tabs on the plate would extend past both sides of the wheel.  Like this, viewed from above:

- = metal plate
x = wheel

-----------         
-----------
------ xxxxxxx
------ xxxxxxx
-----------
-----------

Drill holes through the tabs, near the ends, so as to insert a post extending upwardly and perpendicular to the plate.  The "posts" could simply be a small bolt.  Possibly with a piece of loose aluminum tube over the bolt, so that it would rotate freely around the shaft of the bolt.

Why?  This would provide a rest for the edge of a knife as it was pulled across the wheel, providing an absolutely steady, even distance from edge to wheel.  You might call it the MSS System (Machete Sharpening System).

Everything nowadays needs to be a "system". Or even better... "Now... with MSS Technology!"

[Herman Trivilino]

Then when you wanted to use it, there would be almost no setup time.  Just slide it on, clamp it down and Bob's.... (Doh!...  Rob!) your uncle.  No messing around with screws and nuts, and it would work with no modification to the scissors rest.

This might be a good idea for a future prototype.  Right now it works ok with just the two screws to install.  That's a pretty quick set up.

The biggest problem with this jig is going to be rust.  It's going to take due diligence to keep it dried and oiled between uses.

[Herman Trivilino]

I can see how this jig may surpass the knife jig for sharpening all knives, not just small ones.  One advantage it has is that it keeps the bevel angle constant all the way to the knife tip.

This was what I was referring to in a different post in another thread. I personally like the bevel angle to be the same all the way to the point of the tip. Yes, the width of the bevel grind will become greater on the tip, but remember the tip as it goes out to the point, gets thicker.

I'm not following you.  It seems to me, and practice confirms, that the width of the bevel stays uniform.  The grindstone should touch the blade in such a way that it's tangent to the blade's curve.  If the bevel gets wider the edge angle gets smaller, and my point was that we can avoid that effect with this jig.

[Herman Trivilino]

Drill holes through the tabs, near the ends, so as to insert a post extending upwardly and perpendicular to the plate.  The "posts" could simply be a small bolt.  Possibly with a piece of loose aluminum tube over the bolt, so that it would rotate freely around the shaft of the bolt.

Ok, I follow you so far.

This would provide a rest for the edge of a knife as it was pulled across the wheel, providing an absolutely steady, even distance from edge to wheel.  You might call it the MSS System (Machete Sharpening System).

Would this be the cutting edge of the knife that runs along the wheel?  It seems it would have to be positioned just so, and if you changed to a different grinding angle you'd need it in a different position.  Maybe I'm not understanding you.

[Herman Trivilino]

After a trip to the hardware store that bore no fruit for design innovations I came back home and made one more modification to the jig.



As you can see I trimmed off the excess metal and gave up on countersinking the attachment screws.  That tool steel is just too hard and I don't have a drill press.  Plus, there's really no need as the screw heads are not in the way.

I sharpened my machete with this jig today and it did a wonderful job! 

I also sharpened my precious Buck pocket knife removing almost no steel from the edge.  When I look at the bevel with a magnifier I can see that only the slightest amount of steel has been removed.

This jig is a dream to adjust.  With the set screw on the scissors jig loose the platform is balanced as it rotates.  If I set it on the grindstone it stays there.  I can set the angle master on it and rotate the micro adjuster on the universal support until I get the grinding angle just right.  Then tighten the set screw on the scissor jig, raise the platform off the grindstone by turning the micro adjus ter just a few degrees, and tighten down the set screws on the universal support.

I will be on the lookout for a scrap piece of flat aluminum in the shape of a rectangle, maybe 3/16" thick and measuring 3" by 5".  This would be ideal as it wouldn't rust.

[grepper]

Yes, Herman that would be the idea.

Is that now how the jig works?  You set it for a particular angle, and then, with the knife flat against the jig, pass the knife over the wheel?

The "posts" would simply keep an even distance from wheel to the edge of the knife.

Am I misunderstanding how the jig works?

Please forgive me, and keep in mind that not all of my ideas are fully baked.  Some may not be baked at all!  I'm intrigued by the jig, and and am just running ideas by you as I'm interested in your perspective.

Ok. I just saw your latest post.  Maybe posts are completely not needed with just a little skill from the operator.

So, it worked great for a machete!  How cool is that Herman!  Nice job job on chopping it off to match the width of the tool rest. 

I take it that when sharpening the machete, you kept it pressed against the tool rest and got a consistent bevel angle?

[Herman Trivilino]

I take it that when sharpening the machete, you kept it pressed against the tool rest and got a consistent bevel angle?

Yes, same with a pen knife blade, or anything in between.  You hold the blade firmly on the top of the platform and slide it down until it touches the grindstone, then you just move it from side to side.  You have to try it to believe how well it works.

I can see this replacing the knife jig.  It's awesome!

I put a 30^o edge angle on a paring knife, a 40^o edge angle on my Buck pocket knife, and a 50^o edge angle on my machete.