Turning in Iraq, first practice piece/technical advice needed

[dave barnhart]

Attached is my first practice run making the gavel head. My skew jumped (and gouged) the piece when I was rotating it into the work. You can see in the picture. I just can't remember what mistake I made to allow this happen. Any quick advice to combat this problem is appreciated. (I only have two more pine blanks to practice on.)

The beads on the head are different purposefully. I was making a comparison between the narrow bead and wide. I'm going with the wide.

Oh, if you look at the growth rings on this wood they are 3/8" wide. I have seen some wood here that is over 1/2" wide growth rings.

Thanks

[Dean Thomas]

Just had a group lesson in skewing today, actually. I can offer a little from what he shared and a little from my own experience.

Teacher shared that the skew MUST be travelling in the direction of the cut. That seems like a "doh" answer to a serious question, but I think I understand what he was saying. It relates to basic lessons in physics.

SHARP skews should always be used. Dull causes problems.

Whether you use the skew with long point up or long point down, you only have a very small "sweet spot" in which to cut without catching. That seems generally to be up about 1/8" from whichever point is at the bottom and to a little bit below the center of the tool. If the skew is 1" in length, that means that you have between 1/4" and 5/16" of sweet spot. Once you hit center, you're risky. If you're in the lower 1/8", you're really risky! Corners will get you nearly every time.

If you're making a shearing cut, across the face of the spindle, you need to aiming the skew--pushing it or pulling it--so that the edge is moving toward the direction of cutting. Does that make sense? You can do all sorts of things with a gouge and still cut wood. Not with a skew. Another way to say that is if you're pushing to the left, the handle of the tool is going to be on your right side and visa-versa.

Lastly, the angle of cut for that cut along the cylinder. Bevel gliding, your cutting edge should be more than 45º, IMHO, to the length of the lathe. If you decrease the angle, the edge of the tool gets flatter and wider (parallel) to the wood, violating the sweet spot rule above. Danger, danger, danger. Or just dang, dang, dang! :p

The steeper the anger, say the closer to parallel, you get, the finer a thread you'll pull, but once you get too straight, you won't cut much at all. Counterproductive.

Does that help at all??

[Gene Kennedy]

I'll just add that I get a lot fewer catches when I set my tool rest up really high on whatever I'm working on. Whenever possible I try to stay a little over halfway between the centerline and the top of the piece.

[dave barnhart]

Much of that actually makes sense once I visualized how I run the skew. I keep these as sharp as I can, but they are 'made in china' (Grizzly needs to hold the Chinese company to a higher QA standard).

In the end it sounds like I just need to practice rolling the skew to cut the end grain and make that deep convex shape. I got it to work on a couple sides.