holding thicker knives

[Ken S]

The Tormek knife jigs must be able to accommodate thin and narrow knives, such as paring or fillet knives and have enough clearance to hold them for relatively acute angles.    This puts a constraint on the jig's ability to properly center thicker knives.

Tormek has devised the Small Blade Tool. This tool is mounted in the regular knife jig and holds small bladed knives by the handle.

Wootz has clever developed a modification of the standard knife jig by milling the 1.25 centering recess deeper.

I propose a slightly different approach. A pair of holding jaws, one fixed, one movable (to tighten) could be mounted in the regular knife jig (actually just the fixed jaw would be held in the jig.) These jaws could be thicker than those of the standard Tormek knife jigs. A thicker knife would generally be larger and probably ground less acutely, thereby allowing the jaws to be thicker.(clearance not being as critical)

The fixed jaw would have a milled rabbet (groove in woodworkingese) milled from beneath 1.25mm thick in order to center with the jig axis. The milled area would be large enough to fill the entire knife jig holding area. This would allow the side of the fixed jaw facing the grinding wheel to have whatever milled depth was needed to center the work.

Machining would be relatively simple. The fixed jaw would require one face to be milled to 1.25mm. The other face would be milled to the desired centering depth. This jaw would also be drilled and tapped for the clamping screw(s). The movable jaw would only need to be drilled for the holding screws.

Two springs would hold the jaws apart.

The holding tool might require more distance than the standard universal support can offer. In that case, Robin Bailey's extended universal supports would resolve things.

Wootz' idea of feeler gages would also work with this set up.

Due to the small market, this tool would need to be made up by a machine shop.

Thoughts?

Ken

[Jan]

Ken, you are really very inventive and creative man. 

The advantage of your idea is that the Tormek knife jig will remain unchanged. 

On the other hand I am afraid that the Wootz solution in its simplicity is hardly surmountable.   

Jan

[Ken S]

Jan,

I share your high opinion of Wootz' solution. This is just an alternate idea.

I wish I had learned how to use my father's Unimat (a small metal lathe and mill). This is one of many projects I could have done with it.

Ken