Machete - curved blade - how to sharpen.

[piotr.galecki]

Hello,

I have a request for help in choosing a sharpening method for a Fikars XA23 WoodXpert machete with a curved blade on the Tormek T-8.





I would like to ask for help in choosing both the appropriate method of attaching the machete (in which device and how to attach it), and the method of conducting the correct sharpening of the blade curved inwards.

Thank you in advance for any suggestions.
Piotr

[Ken S]

Piotr,
Here is advice directly from Tormek's experts:

https://www.youtube.com/live/aw4vJSUPXmk?si=hb1TbSq8YbVABkpr

Ken

[tgbto]

Hi Piotr,

No jig will help you sharpen such a blade on the Tormek. If you use a jig you will only be able to sharpen the convex part of the blade, and you will dent/overgrind the concave part.

So you're pretty much left with (freehand) grinding on the (rounded out) shoulder of the wheel, and the convex part will be quite finicky. Grinding on the side of the wheel increase the pressure *a lot* so you're on dangerous ground.

Give it a shot if you "only" have a Tormek, but with low pressure and checking your work often. I'm not sure with the shape of the wheel and the shape of the blade you'll be able to grind everywhere at the desired angle, and honing will probably be even worse. So I'd "hone" with a ceramics rod instead of the leather wheel in the concave area.

If I had to do that I'd rather go with a rod-based sharpening system with a semicylindrical/triangular stone, or a belt sander with a slack, thin belt. That would give much more control.

[piotr.galecki]

Hello,

First of all, I would like to thank you very much for both answers.

Unfortunately, they confirm my fears that sharpening a blade of this shape can be a difficult challenge.
I also wonder if using a grinding wheel that is significantly thinner than the standard Tormek wheel (50mm) would make this easier?
Do such wheels (e.g. 3-5 mm thick) exist and can they be mounted on the T-8?

Piotr

[RickKrung]

Hello,

First of all, I would like to thank you very much for both answers.

Unfortunately, they confirm my fears that sharpening a blade of this shape can be a difficult challenge.
I also wonder if using a grinding wheel that is significantly thinner than the standard Tormek wheel (50mm) would make this easier?
Do such wheels (e.g. 3-5 mm thick) exist and can they be mounted on the T-8?

Piotr

Indeed they can, with a some accommodations.  Ken S. has said many times before that a stand 1" grinding wheel can be mounted on a Tormek, run in water and used just like a regular Tormek grinding wheel, including truing with the Truing Tool.  It requires buying or making a bushing to mate the 1" grinding wheel's arbor hole (often 1") with the 12mm Tormek shaft.  Many new standard grinding wheels come with a set of plastic bushings in about 1/8" diameter increments.  As I recall, Ken drilled a piece of PVC pipe with a 12mm drill to bore out the ID to fit the shaft.  He also used multiple 12mm ID fender washers to build up the width to serve as flange washers. He recommended Norton 3X, 64 grit wheels.  80 grit can also be used. 

I have done this with two different sets of wheels for my T8, two 8" Norton 3X wheels, 64 and 80 grit and and a 10" no-name wheel.  I machined stainless steel bushing and custom aluminum flange washers, but Ken's method works fine.  The most important aspect is matching the shaft diameter with the bushings.

Here is a video of truing one of these.

The point of the above adaptations was to provide a more aggressive metal removal option to the range of Tormek wheel grits and are very effective.  They may work for what you are asking about but I think the corners would need to be rounded quite a lot to be more effective.  How often would you need to do this? 

Rick