Author Topic: Long Knife Jig asymmetry problem  (Read 24278 times)

Offline texaspro

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Re: Long Knife Jig asymmetry problem
« Reply #105 on: February 15, 2019, 06:54:12 am »
#1 - wow, that's just awesome. You must have genuinely been curious about these jaws to go through all of that!

#2 - Interesting idea. Did you try it the way I suggested and was it offline? Was there any method that yielded an offline grip? I want to be certain I did indeed resolve the issue and didn't just get lucky on this one, before moving to another knife. Your setup is great!

Offline RickKrung

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Re: Long Knife Jig asymmetry problem
« Reply #106 on: February 15, 2019, 07:14:34 am »
#1 - wow, that's just awesome. You must have genuinely been curious about these jaws to go through all of that!

#2 - Interesting idea. Did you try it the way I suggested and was it offline? Was there any method that yielded an offline grip? I want to be certain I did indeed resolve the issue and didn't just get lucky on this one, before moving to another knife. Your setup is great!

#1 - yes, I was really curious, but also perplexed.  As some may think but have not said publicly, I can go a bit "over-the-top" on things, sometimes... 

And...

#2 - Actually, I'm not entirely clear on what you mean by an "offline" grip.  Do you mean that the blade was out of line with the jig centerline?  That makes sense as that is what I meant by "canted". 

I only tested the surrogate blade when the jaws were either parallel or the top jaw was significantly canted upward causing the blade to be canted downward.  I think the only way to effectively grip a blade and have the top jaw canted is if it is canted upward.  I think it would not make any difference, as long as the blade was caused to be canted also. 

I think you should be safe, just making sure the jaws are parallel and firmly gripping the blade.  It would be good if you tested it, however, to satisfy yourself.  I would use some "test" knives for it. 

Rick
« Last Edit: February 15, 2019, 07:16:11 am by RickKrung »
Quality is like buying oats.  If you want nice clean, fresh oats, you must pay a fair price. However, if you can be satisfied with oats that have already been through the horse, that comes at a lower price.

Offline cbwx34

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Re: Long Knife Jig asymmetry problem
« Reply #107 on: February 15, 2019, 04:36:27 pm »
Rick is "spot on" in his assessment.

I think "offline" means getting a blade that is the appropriate width, to grind one side more than the other because it wasn't clamped correctly.  The answer to that would be yes... as Rick points out, it will cant the blade... in fact, there is a post of a user adjusting the knife by manipulating the two screws HERE.
« Last Edit: February 15, 2019, 04:41:23 pm by cbwx34 »

Offline Ken S

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Re: Long Knife Jig asymmetry problem
« Reply #108 on: February 15, 2019, 05:38:22 pm »
We are expecting a lot from one relatively inexpensive knife jig. We expect it to accurately grind both bevels of knives with quite a range of thicknesses and blades which are are not parallel.I think Wootz is moving in the right direction by dedicating four jigs to achieve this goal.

I believe the final solution will be one or perhaps a series of more advanced, self centering jigs. This will be a demanding order for Tormek. I would guess it will sell for a much higher price and in considerably smaller quantities if Tormek decides to go forward with such a jig.

I do not see such a jig being a practical investment for the hobbiest of part time sharpener.
I would like to be wrong.

Ken

Offline GKC

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Re: Long Knife Jig asymmetry problem
« Reply #109 on: February 18, 2019, 05:44:39 am »
I believe the final solution will be one or perhaps a series of more advanced, self centering jigs. This will be a demanding order for Tormek. I would guess it will sell for a much higher price and in considerably smaller quantities if Tormek decides to go forward with such a jig.
Ken

I think it is reasonable to expect this of Tormek, and the price should not be out of line with the rest of the equipment.  I have heard that Tormek wants to get deeper into the knife sharpening market (see the T4 Bushcraft), and it is my view that if you want to be a serious contender in this field you need to have a good self-centring jig.  Other systems have them.  The TSProf has a good self-centring jig on a rod (like a Tormek jig), I can't see why Tormek couldn't do this.

Gord

Offline texaspro

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Re: Long Knife Jig asymmetry problem
« Reply #110 on: February 18, 2019, 09:15:16 am »
We are expecting a lot from one relatively inexpensive knife jig. We expect it to accurately grind both bevels of knives with quite a range of thicknesses and blades which are are not parallel.I think Wootz is moving in the right direction by dedicating four jigs to achieve this goal.

I believe the final solution will be one or perhaps a series of more advanced, self centering jigs. This will be a demanding order for Tormek. I would guess it will sell for a much higher price and in considerably smaller quantities if Tormek decides to go forward with such a jig.

I do not see such a jig being a practical investment for the hobbiest of part time sharpener.
I would like to be wrong.

Ken

I just wish they would figure out a way to use the jig that comes with the T-2, on the T-8. To me that is a true jig.

Offline cbwx34

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Re: Long Knife Jig asymmetry problem
« Reply #111 on: February 18, 2019, 03:29:05 pm »
I just wish they would figure out a way to use the jig that comes with the T-2, on the T-8. To me that is a true jig.

Herman’s Homemade Knife Rest will do this.

(A video demoing it)...  https://www.youtube.com/watch?v=AcWAkQmoU8c

Offline Ken S

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Re: Long Knife Jig asymmetry problem
« Reply #112 on: February 19, 2019, 12:47:10 pm »
I just wish they would figure out a way to use the jig that comes with the T-2, on the T-8. To me that is a true jig.

Herman’s Homemade Knife Rest will do this.

(A video demoing it)...  https://www.youtube.com/watch?v=AcWAkQmoU8c


The jig on the T2 is designed to allow restaurant staff with very little sharpening experience to sharpen most kitchen knives. Neither the T2 nor its built in jig were designed to be used by skilled sharpeners.

I agree that the homemade knife rest (Herman's small platform) works well. The T2 knife jig can be converted into a small platform, however, the conversion is expensive. Tormek does not want the T2 to be used for anything more than basic kitchen knife sharpening by kitchen staff with the built in knife jig being used conventionally.

A sharpener is much better served with a T4 or other Tormek and the traditional Tormek knife jigs. This arrangement allows a sharpener the flexibility to use his skills.

Ken

Offline Darrell C

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Re: Long Knife Jig asymmetry problem
« Reply #113 on: February 21, 2019, 07:22:03 am »
 
Quote

Herman’s Homemade Knife Rest will do this.

(A video demoing it)...  https://www.youtube.com/watch?v=AcWAkQmoU8c

Now I like that, gotta make me one, thanks for the link..........

Offline Ken S

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Re: Long Knife Jig asymmetry problem
« Reply #114 on: February 21, 2019, 08:52:43 am »
Don't be tempted to use the Torlock platform instead of the platform from the scissors jig. Been there; done that; the higher center of gravity does not work as well.

Every Tormek knife sharpener should have a small platform jig.

Ken

Offline andrew08

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Re: Long Knife Jig asymmetry problem
« Reply #115 on: March 14, 2019, 04:37:07 pm »
I generally have the right side as convexed as I can, and I even keep the shoulder on the left one on purpose in some extreme cases. But steering is a very individual matter. Get used to it, loosen your grip and little by little you will compensate for it and need less correction of the geometry.

A good trick to see how the blade itself behaves is by making a cut without any pressure, only with the blade's weight in the inverse sense of your normal cutting. If you normally push, try this pulling and vice versa. See under which angle cuts the best.

Offline smurfs

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Re: Long Knife Jig asymmetry problem
« Reply #116 on: October 17, 2019, 11:09:57 pm »
Apologies for resurrecting an old thread but I found this discussion on uneven bevels extremely informative and I wish to make an observation which I think is relevant which doesn't seem to have been mentioned (although it has possibly been made in another thread I've yet to read  :D).

What prompted me was the following post from texaspro...

<snip..>. I already know that my 2.5mm wide blade (Benchmade Mini Griptillian) in the SVM-45 is not the same on both sides. I am trying to figure out why and how to fix it. Unfortunately putting shims in the jig or grinding the jig down as Wootz suggests, is not applicable on 2.5mm wide blades (his method is more for under 2mm or over 3mm, from what I understand).

To be perfectly clear, the problem I am having is an uneven bevel (one side is higher than the other). No matter what I try, the angle is always different on one side as opposed to the other, causing the bevel to be higher on one side.

I can think of two scenarios where uneven bevels could occur with a perfectly centered blade, i.e 2.5mm in thickness. The first would be an uneven number of grinding passes on each side of the blade, and/or the uneven application of pressure during each pass.

It may seem obvious, but having a perfectly centered blade will not guarantee a symmetrical bevel. It also requires that refined human touch!