Ken Whitney
03-12-2011, 9:48 AM
Well, jig may be too strong a word for this.
186302
I really like the raptor-style templates for setting the platform and pocket on the Wolverine grinding system. Being able to quickly set a known angle minimizes set up time and also minimizes tool wear, since you don’t have to hunt around for the matching angle like you do when you are setting the system directly from the tool.
The Raptors don’t appear to have an angle suitable for skew chisels, though, so I came up with this very simple way to consistently set up the platform to do skews.
The “jig” consists of two pieces of ¾” aluminum angle, one about 1 ½” long and the other just over an inch long.
186300
The method works as follows:
1) Insert the long angle piece on top of the platform arm. Slide the platform toward the grinding wheel until it stops against the angle piece. Lock the arm in place and adjust the platform until it is parallel with a tangent of the wheel (see the photos, it is probably easier to see than to explain). I use the edge of the skew to line up the platform with the tangent, but a ruler or straightedge would work as well. Lock the platform in place.
186304186303186306
2) Release the arm, remove the long angle piece and insert the short angle piece. Again, move the platform forward until it stops against the short angle piece. Lock the arm in place. Do not make any adjustments to the platform itself.
186305
3) Sharpen the skew!
186301
This gets me fairly close to a bevel length of about 1 ½ times the thickness of the tool.
I’m sure there is some mathematical formula to determine the relative lengths of the two pieces, but I’ve not found it.
You may need to file or grind part of the weld joining the platform to the arm to get the angle pieces to lock into place reliably.
Good luck.
186302
I really like the raptor-style templates for setting the platform and pocket on the Wolverine grinding system. Being able to quickly set a known angle minimizes set up time and also minimizes tool wear, since you don’t have to hunt around for the matching angle like you do when you are setting the system directly from the tool.
The Raptors don’t appear to have an angle suitable for skew chisels, though, so I came up with this very simple way to consistently set up the platform to do skews.
The “jig” consists of two pieces of ¾” aluminum angle, one about 1 ½” long and the other just over an inch long.
186300
The method works as follows:
1) Insert the long angle piece on top of the platform arm. Slide the platform toward the grinding wheel until it stops against the angle piece. Lock the arm in place and adjust the platform until it is parallel with a tangent of the wheel (see the photos, it is probably easier to see than to explain). I use the edge of the skew to line up the platform with the tangent, but a ruler or straightedge would work as well. Lock the platform in place.
186304186303186306
2) Release the arm, remove the long angle piece and insert the short angle piece. Again, move the platform forward until it stops against the short angle piece. Lock the arm in place. Do not make any adjustments to the platform itself.
186305
3) Sharpen the skew!
186301
This gets me fairly close to a bevel length of about 1 ½ times the thickness of the tool.
I’m sure there is some mathematical formula to determine the relative lengths of the two pieces, but I’ve not found it.
You may need to file or grind part of the weld joining the platform to the arm to get the angle pieces to lock into place reliably.
Good luck.