technique for long flexible knife?

[Zamfir]

Ok, I know it has been asked and I tried searching here and on utube.

I did find Wills mod which looks like a good idea but that will not help me tomorrow.
https://knife.wickededgeusa.com/forum/6-techniques-and-sharpening-strategies/12908-will-s-mods-final#16951

I have a long flexible boning knife I need to sharpen. Even with the extra rod installed it will just flex too much. My only thought was to sharpen a section, move the knife on the vise and do another section.

Is there any videos or advise for how to properly do this? Just eyeball it.. and overlap a bit?

Point me to the wisdom please 🙂 Or if it does not currently exist..if anyone has done it..howdya gone and dun it?

Thanks!
-Eric

[tcmeyer]

Hi Eric:

I can only share with you what I do, which might not impress a lot of people here. Simple stuff.

1. I clamp the knife fairly far back – leaving less of the flexible tip hanging out where it can bend.
2. When stoning the near half of the blade, I hold the handle as steady as I can with the opposite hand.
3. When stoning the far half of the blade, I hold the index finger of my opposite hand along the spine near the tip to hold the tip as steady as possible – applying pressure in opposition to the stone’s pressure.

The tip does flex a little, but I haven’t noticed a significant defect in the bevel or the edge.

[Zamfir]

Well, if no one posts up a better idea.. before I tackle it tomorrow I will try this Tom. thanks..but..I think you and I are the night owls around here lol. Maybe I could just grab one of my mother-in-laws old fashioned heavy irons (the kind you heat on the stove) and duct tape the handle to it while it is sitting on the table to hold it. Then I could clamp even farther back. hmmm…

Tom, have you every done a long blade where you had to sharpen half then re-position on the vise and sharpen the rest? that just seems like a pain to get any kind of consistency with the edge.

thanks!
Eric

[Ziggy]

Hi Eric:

I can only share with you what I do, which might not impress a lot of people here. Simple stuff.

1. I clamp the knife fairly far back – leaving less of the flexible tip hanging out where it can bend.
2. When stoning the near half of the blade, I hold the handle as steady as I can with the opposite hand.
3. When stoning the far half of the blade, I hold the index finger of my opposite hand along the spine near the tip to hold the tip as steady as possible – applying pressure in opposition to the stone’s pressure.

The tip does flex a little, but I haven’t noticed a significant defect in the bevel or the edge.

+1

[tcmeyer]

Well, if no one posts up a better idea.. before I tackle it tomorrow I will try this Tom. thanks..but..I think you and I are the night owls around here lol. Maybe I could just grab one of my mother-in-laws old fashioned heavy irons (the kind you heat on the stove) and duct tape the handle to it while it is sitting on the table to hold it. Then I could clamp even farther back. hmmm…

Tom, have you every done a long blade where you had to sharpen half then re-position on the vise and sharpen the rest? that just seems like a pain to get any kind of consistency with the edge.

thanks!
Eric

Eric:

With straight blades, like slicers or jerky knives, you can move the blade to avoid extreme reaching, but then you have to watch carefully how you blend the grind levels. I go as high as 11-12 inches without moving.

[Zamfir]

So This knife is some supernatural flex monster. It tapers to the last 1.5 inches of super flex..I mean there was no way no how holding my finger on it would have allowed me to sharpen it in less than a day…lol.. I mean without what I did, not sure how to sharpen it easily.
Notice the blade tapering until the last 1.5inches? The whole blade is very flexible and this last 1.5 inches is ridiculously flexible.

Old Hickory knife says Shapleigh’s hammer Forged 1843-1934. I was able to resolve my flexing problem with a few implements sitting around my In-Laws house…

2 pieces of 4×6
1 WearEver Aluminium Pan—(I have the Josh Vacuum mod to mine and did not feel like doing all of this on the counter and the wood table is antique wood and not very flat)
1 Cast iron and cement mobile bumblebee horse tie down
1 rubberband
various sheets of newspaper for shims

Then I just mounted it at the tip with the handle back and supported by the Horse tie down. It worked real well. He wanted a point on it so I fixed the rounded point for him with the 80 grit diamond paddles..shoot it was already as dull as the spine so what the heck..ground her down. .But now it is sharp..and pointy.. :woohoo:

Thanks for the suggestions guys. Next I will do a Rapelea fillet knife. That thing is a little flexy..I can do the finger trick with that one..lol.

Attachments:

• thinthinthin.jpg
• oldhickory.jpg
• olhickorytipbefore.jpg
• olhickorytipafter.jpg
• olhickorysetup.jpg
• olhickorydone.jpg

[Gregg776]

Since you are using a suction base vise, it would be fairly easy to add an additional clamp to another vise for long knives. The Ram clamp ball and sockets are very sturdy and reasonably priced. Here are some pictures:

Attachments:

• Auxclamp1.JPG
• Auxclamp2.JPG
• Auxclamp3.JPG

[tcmeyer]

Hi Eric:

I did a batch of filet knives for a friend just before Christmas. I used the finger support system and it worked out OK for me. Of the seven I did (two were Rapalas), four of them (including both of the Raps) reached out and nicked me. Two of the cuts were within a quarter-inch of each other on my left thumb and on sequential nights. The very, very pointed and flexible tips are really nasty. Instead of scratching you as you go by, they dig in and follow you for a ways.

And to Gregg, Kudos! Very well executed. I gotta get one of those.

[CliffCurry]

Aloha Greg, is the vice and attachments shown part of the ram clamp or did you hand fabricate those? Seems like a great way to go!

Thanks,
Cliff

[Gregg776]

Cliff,
I made the clamp out of a piece of bar stock I had in my bucket of metal sticks. It is soft steel, maybe keystock. If I were buying new I would probably chose a better alloy. The ready made machinist parallel clamps are hardened and I wanted both screws on the same side, unlike most of the manufactured ones. Grizzly has them at a good price if you want to try annealing one or you could silver braze a nut where you want to attach the Ram ball.
I cut the bar of steel on a diagonal through the middle with a parting disk and finished the surfaces with a belt sander. I drilled and tapped a lot more mounting holes than I needed because I wasn’t sure what I needed.
The Ram mount parts are available on Amazon; there are different sizes and many options, the “B” size is the 1″ diameter ball. Get part numbers from the Ram website to make searching for what you want easier http://www.rammount.com; this is their catalog of parts:

You want to avoid the aluminum stud like part# RAM-B-237U and plastic (composite) clamp parts and it is sometimes difficult to tell what you are ordering. Some part numbers:
RAP-B-400U
RAP-B-200-2U clamp that pivots in the middle
RAM-B-337U or RAM-B-348U female thread; use a setscrew for a stud if you want
RAP-B-379U-252025 ball with steel stud; Amazon part# B00AHCUNG2
The possibilities with the Ram system are mind boggling.
-Gregg

[Zamfir]

Ram mounts are freggin sweet! Ohh the options. Now I know how to put a cupholder on my cheapo zero gravity folding chair!

and how to put a cupholder in the correct place in my vehicle!

And how to make some cool flexy knife holders like you made Gregg! Thanks a ton! Never seen these before..

[Author]

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