beyond knives

[Ken S]

The Kenjig, formerly known as the knife setting tool, was primarily designed for knife sharpening. However, the original idea was  for chisels, and it is not limited to knives or chisels.

When held in the Tormek knife jigs,  the projection of the knife edge beyond the universal support combined with the distance between the universal support and the grinding wheel will determine the bevel angle. This is equally true for chisels and planes in the square edge jig as well as turning and carving tools.

The projection and distance can be determined by using the Anglemaster WM-200; using a black marker; the Turning Tool Setter TTS-100; the Kenjig; or Dutchman's trig tables and a rule. The method of determination does not matter; a given projection and distance will produce the same bevel angle. Being familiar with the various methods gives the Tormek user the flexibility to choose the method he feels most appropriate for the situation.

As I have stated before, only the application is new. The concept of using gage blocks to set the distance between the universal support  and the grinding wheel goes back to the invention of the universal support and is shown in the handbook. The Turning Tool Setter TTS-100 demonstrates a refined method of  accurate and repeatable setting of both the distance and the projection. (It also compensates for stone wear automatically, something which must be done manually and only very occasionally with the Kenjig.)

If a chisel is placed in the Square Edge Jig to a convenient projection length, the distance between the universal support can be set by black marker or the Anglemaster. Once these variables are determined, a blank Kenjig can be marked with the projection distance of the chisel or other tool, just like the knive version is marked. The slot is cut to the universal support distance. Once this is done, all future chisels or other tools with the same desired bevel angle will not require any measured set up. This is especially desirable for those with older eyes or anyone who must work in less than perfect light. It also eliminated error do to measuring errors.

I made the tool with baltic birch plywood offcuts. 12mm thickness (half inch) works well, although any thickness of plywood or even cardboard of matboard will also work. Any width between 18mm and 30mm (three quarter inch and inch and a quarter) works. A length of at least 150mm (six inches) allows the cut away for the universal support to be long enough for any distance the universal support will work. It also allows any commonly used projection distance. There is no reason why the tool can not be longer than 150mm, except for convenient storage.

I cut the blanks to shape with my table saw and the cutaway with my bandsaw. The width of the cutaway is approximately the diameter of the universal support. My initial run was eight blanks. I have given most of these away. The next run I make up will be more, perhaps twenty. (The exact number will be determined by the size of the plywood offcut I start with.) A smallish piece of  plywood, perhaps 600mm square or rectangular (two feet by two feet, more or less) should provide a lifetime of Kenjigs. I suggest cutting the long side of the cutaway during initial construction.

When a new tool needs a Kenjig, the projection is marked on one side. Using the end opposite the cutaway small end seems logical. The distance from the universal support and the grinding wheel is noted, market on the area to be cutaway, and this last task is easily completed with a compass saw or dovetail saw. (By precutting the cutaway long cut, there is no need to set up the bandsaw again.)

When the accuracy of the gage block has been tested, it should be labelled, noting the bevel angle and tool (or tool type). The next time that tool type is sharpened, setup is quick and accurate.

Happy sharpening,

Ken