Forza Corsica

[tgbto]

Hello all,

I'm still getting to grips with my new T8. Today's target is a corsican knife made in the hills around Ajaccio by a renowned knifemaker (Biancucci). I have no idea what the steel is, I just know it is NOT stainless and the forging process involves tempering in ice. I'm not sure what happened to this knife, but close to the heel the bevel was shorter and the blade ground in an akward fashion.

As you can see (C1.jpg), it is a thick and bulky blade, with a high curvature in the tip area. It also has a very thick heel. I used the setup template from Jan to have a reproducible setup, and it curves upward much more quickly than the template. I also used a reference line on the stone with a laser pointer.

To make sure I didn't miss anything, I tried to first lift (airplane roll) the handle only. As expected, the edge would quickly run higher up the stone, with a very high angle (C2.jpg). I then tried to pivot (airplane yaw) the handle rather than just lift it. However, the blade being very short, and because of the flat handle on the SVM-45 jig, the distance between the blade would also increase quickly (albeit not as quickly as when only lifting). (C3.jpg)

Back to the paper template, but this time with the triangular-shaped pivot jig (C4.jpg). With a lot of pivoting and a bit of lifting, this improved dramatically. It would still get further up the wheel, but much less than before (C5.jpg). I had to reverse course at some point over the US, because the pivoting action would bring the tip closer to the edge of the wheel. And boy it ended up sharp after honing on felt/1µ diamond spray.

As you can see (C6.jpg), I did not completely correct the area where the bevel is much thinner (I'd have to remove a lot of steel, and probably reshape the heel). You will probably also notice that in the first part of the curvature, the bevel is wider. At the beginning of the pivoting action, the edge would drop for a short while below the laser line, so no surprise here.

And that had me thinking that maybe a pivot jig with a variable flat area  (if this is not clear i'll sketch something) might help. Or maybe the SVM-45 with just the handle upside-down, who knows. Or the one sold by wootz. Or maybe somehow bringing the svm-45 backwards to keep the edge on the line, no longer resting over the US, but that would be detrimental to consistency.

Well, your feedback is welcome. The tormek is not even a month old and I got kids, so we're talking a few hours of experience on it. Still, I think the compromise between speed and quality is very promising.

[cbwx34]

Edit:  My bad.. I reread your post... you already are doing what I posted.

[cbwx34]

Ok... I actually read your post. ...

One thing you can try, since you have a laser guide is to completely remove the handle or stop collar.  You still use the USB, but keep the blade on the line... like in the top set of photos...



... you're still using the USB, just give you a bit more freedom to manipulate the blade.

[tgbto]

Thank you for the input, I will try to do that. Do you still feel like you have a lot of control when you sharpen that way ? Or is it tormek-tatoo-prone ?

I will probably do it on a few inexpensive knives and on the SG only (not SJ) before I get back to this one !

[cbwx34]

Thank you for the input, I will try to do that. Do you still feel like you have a lot of control when you sharpen that way ? Or is it tormek-tatoo-prone ?

I will probably do it on a few inexpensive knives and on the SG only (not SJ) before I get back to this one !

Yes, you can maintain control... and definitely practice.

What is "tormek-tatoo-prone"? 

[tgbto]

What is "tormek-tatoo-prone"? 
[/quote]

I was referencing this : https://forum.tormek.com/index.php?topic=1568.msg6183#msg6183

[cbwx34]

What is "tormek-tatoo-prone"? 

I was referencing this : https://forum.tormek.com/index.php?topic=1568.msg6183#msg6183

Ah.  (Before my time).