Sharpening Jig and chisel sharpening questions

[starmatt]

I've just started getting into a little bit of turning on my mark v and have been reading up on tool sharpening. I'm thinking of building my own version of the sharpening jig for the disk sander. In thinking about that I have a couple of questions:

1. The angle listed for the parting tool on the blackboard for the sawdust session is 30 degrees (presumably each edge is 15 degrees from the center line). The angle on the sharpening guide appears to be around 25 from the center (leading to a total of 50). What angle should I use? I know there's some personal preference that goes into these angles, but any insight would be helpful.

2. I can't quite figure out how the channel for the skew should be shaped since there's a compound angle. The sawdust session suggests each side should 15-22.5 degrees from the center line (30-45 degrees total), but it says nothing about the 20 degree or so angle of the tip (just that with the tip up, you push it against one side of the channel, with the tip down you press it against the other side). Is that channel slanted? It seems there would need to be two slants (one up and one down) depending on which side of the chisel you're sharpening.

Any advice would be appreciated.

[levier2011]

Sharpening the skew on a cicrular sander might be a little some practice but i have 2 possible solutions for you

check on youtube a video on how to sharpen the Alan Lancer Skew and the guy that is making the video is not using a jig.

also take your time and check my sharpening videos on youtube user name levier2011

[nuhobby]

I've just started getting into a little bit of turning on my mark v and have been reading up on tool sharpening. I'm thinking of building my own version of the sharpening jig for the disk sander. In thinking about that I have a couple of questions:

1. The angle listed for the parting tool on the blackboard for the sawdust session is 30 degrees (presumably each edge is 15 degrees from the center line). The angle on the sharpening guide appears to be around 25 from the center (leading to a total of 50). What angle should I use? I know there's some personal preference that goes into these angles, but any insight would be helpful.

2. I can't quite figure out how the channel for the skew should be shaped since there's a compound angle. The sawdust session suggests each side should 15-22.5 degrees from the center line (30-45 degrees total), but it says nothing about the 20 degree or so angle of the tip (just that with the tip up, you push it against one side of the channel, with the tip down you press it against the other side). Is that channel slanted? It seems there would need to be two slants (one up and one down) depending on which side of the chisel you're sharpening.

Any advice would be appreciated.

1. The parting tool takes a beating, so I like a slightly bigger angle for durability. I touch mine up often sliding it across a stone or sandpaper manually.


2. Yes, that channel looks like a "V" in cross-section. One time I worked out the trigonometry for relating all the angles in a skew grind, but I've misplaced it. Anyway, the moment the skew-chisel is rested in either side of a "V" rather than straight up&down as applied to the sanding disk, a skewed grind will result on the end. My Guide is buried right now so I'll have to measure the V-angles sometime later.

Happy Turning!

[algale]

Even though you are building your own jig, there's a good two part video on the use of the jig that may answer a few questions or give you some ideas.

Here's the link to the thread which then has the video link.

http://shopsmith.net/forums/showthread.htm?t=9400

Al