Tenon Removal

[mbg]

OK trying to learn this hobby. When I reverse my bowl to work on the foot I have a small issue at times where the gouge wants to run toward the center (like when starting a cut on the rim of the bowl if you don't have a bevel it will run outward). I have the gouge parallel to the floor, flute closed, and the tip bevel close to parallel to the ways and when I start the cut more often than not it grabs and want to go to the center. Any help appreciated.

Mike

[iclark]

I do not know if that is a typo or not about the tip bevel. I can not picture how you can do that if you are using the tailstock.

You want the tip bevel perpendicular to the ways. That is the same way that it is oriented when you are dressing off the end of a spindle if you are cutting (rather than scraping).

You want to be riding the bevel as you start the cut. So, (in simplest geometry description):
gouge parallel to floor
tip at center line height
flute closed and pointing away from you
tip bevel perpendicular to ways/axis-of-rotation.

With the gouge in that position, you should be able to touch the tip to the round and create a thin groove. Then, when you rotate the gouge slightly, the bevel can ride in that groove that you just made.

Good lighting helps a lot, too.

[mbg]

I'm not explaining it well. Look at 7:30 in this video:


https://www.youtube.com/watch?v=Vdn0PdySkh4


when I enter the cut sometimes it wants to pull toward the center - not bad.


Mike

[iclark]

Makes more sense now, Sorry that I did  not understand the first time.

What I described is what he is doing at the 9:09 point.

In order to stop the skating when you use the technique that you are talking about at the 7:30 mark, you need to start by creating a slight groove when the tip first touches the wood. As MM pointed out, part of doing that is having a good strong anchor (strong, not muscular) as a pivot for bringing the gouge up to the wood.

My vocabulary is weak on this, so I hope that I can explain what I mean.

You want to start with the tip of the gouge coming in and touching the wood with the flute fully closed. If the gouge is parallel to the floor, then the tip will be at the same height as the center of rotation.

The tip bevel should be slightly beyond parallel with the axis of rotation. The heel of the bevel should be slightly closer to the axis of rotation than the tip.

Then, when the tip touches, it will cut that thin groove that you can use to stop the skating as you start to open the flute. It is the same sort of groove that you would get by lightly touching the wood with the long point of a skew.

In that section of the video, he is cutting on the tenon nub and then shear scraping on the bottom of the bowl.

[MichaelMouse]

Don't cut outside in, but inside out, so you're going downhill down grain. Swing the tool into the cut until the desired shaving is obtained, then maintain that angle as you move downhill. 

The fat guy in the mortise bottom video cuts inside out, most of the time.

[mbg]

Thanks to all for the help. Think I had two issues: 1) had the flute open a bit too much at start of the cut. 2) I forgot to clean the bottom of the tenon first. It was a little wavy since this is a twice cut bowl.


Thanks,

Mike

[MichaelMouse]

OK trying to learn this hobby. When I reverse my bowl to work on the foot I have a small issue at times where the gouge wants to run toward the center (like when starting a cut on the rim of the bowl if you don't have a bevel it will run outward). I have the gouge parallel to the floor, flute closed, and the tip bevel close to parallel to the ways and when I start the cut more often than not it grabs and want to go to the center. Any help appreciated.

Mike

First, anchor the tool well on the rest.  Use an overhand grip and swing to begin the cut.  Physics wants the tool to run outward unless there's a physical barrier, which is why you start in the middle of the rim and cut downhill to either side, so the point of entry becomes your "stop" cut. 

Not sure what you're asking about the tenon.  Parting is simple parting, but you will have two places where the tool will try to cut upgrain iif cutting faceplate, which is why you start way up top and scrape your way in with a down/inward arc.  Don't have a face-grain series, but if you start like the parting cuts in this long-grain video, you'll be fine. 

http://vid35.photobucket.com/albums/d160...e/Bead.mp4


I work the bottoms like this. But I still haven't figured out how to cut with the bevel on the wood even after all these years, so the tool clearance angle keeps the cut under control.

http://vid35.photobucket.com/albums/d160...rocess.mp4

Addendum : Be sure to draw the parting tool back, feed and widen the cut to keep it from binding and dragging it in.