Custom Shopped TTKZ

[Last Visible Canary]

*bling*

In response to adrock1978's thread about handles turning in your hand while chopping, this is why I consider this a good handle for avoiding torqueing in the hand. The center swell is fairly thick, but throughout it maintains a profile that is more flat then round, especially at the index and pinky positions:
index - 1 3/16" tall, 10/16" thick
middle - 1 7/16" tall, 15/16" thick
pinky - 1 4/16" tall, 11/16" thick

This is a chart of the difference in this custom shopped TTKZ's grind vs. the stock TTKZ and KZ2. It's edge is thinner then the KZ2 up to the the 3/8" mark at which point the CS TTKZ gets a little thicker. The KZ2 has a flat (or nearly flat) grind that starts out thicker, and ends thicker then the TTKZ but is thinner in the middle. If I had continued these measurements you'd see that at the 1 3/4" mark the TTKZ would be thinner then the KZ2 since it's stock thickness is 0.260" vs. 0.295". I realized when measureing this that the CS TTKZ thins out from about 1/2" down from the spine to the spine, going from .260 to .240.

Even though this flattening/thinning didn't quite get it as thin or flat as the KZ2 at the center of the blade, it's a definite improvement over it's original geometry. I would take this over the KZ2 because of it's handle more than anything, as I found the KZ2 handle (even after clipping off the rear top pommel swell) was just to round in the center, making the hand have to grip to hard to keep it in position and pressing to hard on the inner metacarpals (palm bones). I am quite happy with this knife.

I can't really comment on how the balance was affected, as I had a gap between handling it in it's original form and in it's new form, and I don't have a stock model to compare it to. I don't know if my hand strength has built up, or if it's lighter, but it feels less daunting in the hand than I remember.

 

[Bigfattyt]

Nice!

I think my KZII might need a little Custom Shop Diet!


What is funny, is that my old FBMLE felt so heavy when I first got it. Then after a while it was just normal.

The the KZII felt massive. But now, it feels much lighter!

 

[type00rev]

That TTKZ is F'n SWEET!

 

[PeterPHWS]

Very interesting write up LVC ... and your CS TTKZ looks great :thumbup:

I think we share many of the same thoughts in terms of looking for "performance" in a knife ... and that this comes more than anything else from the cross sectional geometry of the blade ... for the knife to chop like a demon the difference in the thickness of the shoulder behind the edge and the general "taper" ratio of the knife from the edge to the spine is critical IMO albeit I can only vouch for this from actually doing chopping with my knives as opposed to having some technical knowledge to explain why ... the best thing I can say is that there is a definite "optimum" in dimensions for a blade and the best way I can describe it is an "apple seed" shape.

You need the section from the edge to 3/4's of the way up the blade grind to be a gradual increase in thickness that is quite shallow ... almost like a high sabre grind with that portion being almost like a flat grind ... then blend in the top part where the sabre grind would be to a less radical transition so that the convex shape is a smooth curve ... this seems to enable the wood to be forced apart more easily after the knife has initially bitten into the wood and leads to a very deep cut ... ideally to the spine ... and the girth in the top 1/4 then enables you to remove the knife without undue sticking ... something which can occur when you have a simple thin flat grind such as on a machete ... which because of the thinness and usually the length of the blade means it bites deep but is a hell of an effort to remove ...

The "incline" ratio needs to also factor in the depth of the blade ... forinstance the short depth on a Basic 11 which has a thickness of .25 at the spine can be a benefit in just leaving the sides of the blade as a "flat grind" ... but the greater depth of the TTKZ at the chopping point means the taper has to be thin and shallow near the edge and gradually widen around the 3/4 mark to enable the wood to be pushed apart ... so for deep blades it is more gradual and for less deep blades a faster increase in taper works well ...

These sort of observations though are not really commented on much in the wider scheme of things on knife forums ... but I am sure a number of custom knife makers pay some heed to this sort of thing ... especially those who focus on competition chopping/cutting blades ... and I know that the Custom Shop is certainly aware of these points as they have been developing ever more capable grinds on the Zilla's as time goes by ...

Your CS Zilla is very similar in grind to the Nuclear Zilla I have which was done on a quasi "flat grind" up to the three quarter point and then had the apple seed shape created where the nuclear serrations began ... this "lighter" blade chops as well as my modified TTKZ and KZII mainly in my view because of the thinner steep profile which it has from the edge to 3/4 point on the grind ...

It would be nice to see this "dimension knowledge" dicussed more ... I really think that this sort of understanding is critical to performance ... :thumbup:

To show what I mean ... if the grind shape dimensions are right you can definately sink the knife deeper when chopping ... and the "apple seed" taper by the spine forces the wood apart for easy withdrawal ...

 

[oge14]

very nice write up's, and sweet knive's.

 

[Last Visible Canary]

Edge thickness and the speed at which a knife thickens up is definitely important, you can feel it doing something simple like cutting an apple. I've had knives from busse that couldn't cut most apples, the edge would sink in a short was (about 1/4") and then the apple would split apart from the force of being pushed apart.

You can tell a lot about a knife just by a measurement of the edge 1/16" up, spine thickness, and height of grind. If it's flat anyways, when your dealing with convex main grinds you really do kind of need a set of measurements like the ones above, or to know what radius of curve they applied, which is a lot harder to understand since it involves math that I don't really know how to do.

I wish I had had this just two weeks ago when I was processing an old dead and many years seasoned apricot tree. The B11 was sticking really badly while splitting most of it, but that was because of how twisted the grain was. I'd have loved to see how the CS TTKZ handled it.

 

[Last Visible Canary]

edge thickness and overall geometry is very important, you'll feel the geometry long before you feel what type of steel it's made of.
(KZ2, TTKZ)

(Tank Buster, Mini Sus Scrofa)

 

[steelnut]

Damn that's HOT!!