Help with cut direction and tear out.

[Grey Darrah]

I'm working on the outside shape of a side grain piece of box elder. It's going to be a flying saucer-ish shaped hollow form. when doing a push cut, if I'm cutting uphill (from the smallest diameter on either end towards the largest diameter area), I get a glass smooth finish off the cut. If I go the other direction (cutting down towards either the smaller top or bottom), I'm left with massive tear out, even with uber sharp tool and taking light cuts.

The biggest problem is the bottom of the form, the area with the tenon in the chuck. I need to get it smaller and better shaped, but because of the head stock, I can't really get my gouge in there (where I need to start the cut) with the bevel riding for a smooth finish.

How else should I approach this cut?

Thanks,
Grey

 

[Dennis J Gooding]

Is it possible to reverse mount your piece temporarily, between centers perhaps, to finish turn the problem area?

 

[Bill Boehme]

You could do a shear cut. It's a bevel rubbing pull cut with the handle dropped 45° to 60° to get much closer. Eventually you will need to reverse it to finish the bottom. You could wait until then. Make certain that the gouge is as sharp as you can get it.

 

[Mike Johnson]

Reverse mounting the piece would be the common practice after finishing the inside, outside and top of the vessel. Another option is having a thicker piece of wood blank to work with which allows more room when working around the face of the chuck. Some turners will glue a waste block on the bottom of the turning blank to mount to a face plate or bowl chuck after you turn a tenon on the waste block. Depending on the size of the wood blank I have a box of tenons turned the correct size that can be quickly glued to the center of wood blank with a flat sanded surface. The precut tenons have a center point which can be centered using the tail stock live center and then use the hand wheel to press the tenon being glued to the wood blank while it is mounted in the bowl chuck or on a face plate. The larger wood blanks will require a larger glue surface which usually requires a larger waste block surface to secure the wood blank to the waste block to the lathe chuck.

 

[hockenbery]

This is a tough area to work.
It is usually an inches or two you can only cut either with a scraping cut or the gouge in the wrong direction.
Sometimes scraping will do well in this area.

This cut can often be done with no tearout by using either a 3/8 spindle gouge or a 1/4” bowl gouge ( I use a Michelson grind). Also Box elder is a pretty soft wood so it need finesse.
Light cuts sharp tool

Most often I turn this area with an advanced cut - it is near impossible to learn in your own-
With the flute straight up at 12 o’clock I cut with the leading edge of the wing of an Ellsworth ground gouge.
This give a pretty clean cut going the wrong way.



I may have this on a video

 

[hockenbery]

I use the flute up cut at about 2:35. In this video it is quick tweak of the curve.
I later cut most of this area with a pull cut and then with a spindle gouge.
What you see here is cutting on the leading edge of the left wing. If the piece were on a faceplate or in a chuck I can cut toward the tenon with the leading edge of the right wing.

View: http://www.youtube.com/watch?v=qZ0fC5Rk6h4

 

[Bob Sheppard]

I'm working on the outside shape of a side grain piece of box elder. It's going to be a flying saucer-ish shaped hollow form. when doing a push cut, if I'm cutting uphill (from the smallest diameter on either end towards the largest diameter area), I get a glass smooth finish off the cut. If I go the other direction (cutting down towards either the smaller top or bottom), I'm left with massive tear out, even with uber sharp tool and taking light cuts.

The biggest problem is the bottom of the form, the area with the tenon in the chuck. I need to get it smaller and better shaped, but because of the head stock, I can't really get my gouge in there (where I need to start the cut) with the bevel riding for a smooth finish.

How else should I approach this cut?

Thanks,
Grey

40 grit gouge. It worked for Bob Stocksdale.

 

[Grey Darrah]

Thanks for the video. That is a very "catchy" looking cut. I'm going to go at it with Bill's shear cut recommendation first. If that doesn't get it, I'll throw a scrap piece between centers and practice your cut.

I use the flute up cut at about 2:35. In this video Here it is quick tweak of the curve.
I later cut most of this area with a pull cut and then with a spindle gouge.
What you see here is cutting on the leading edge of the left wing. If the piece were on a faceplate or in a chuck I can cut toward the tenon with the leading edge of the right wing.

View: http://www.youtube.com/watch?v=qZ0fC5Rk6h4

 

[hockenbery]

Thanks for the video. That is a very "catchy" looking cut. I'm going to go at it with Bill's shear cut recommendation first. If that doesn't get it, I'll throw a scrap piece between centers and practice your cut.

The shear cut is near impossible to learn on your own.
You can get a horrendous catch if you get off vertical a tiny bit.
I learned it from Liam o’neil and got reinforced by David Ellsworth.
A great cut for inside a bowl or for turning the wall of a NE bowl.

Try finding someone in a local club to work with. Ask who has had an Ellsworth class.
A lot folks do this cut and teach it to their advanced students.
Ellsworth and others have taught this cut to lots of people.

It is essential to hold the tool loosely so it can turn to follow the bevel.
Of course it is near universal to tense up and grip the tool tightly and then you can get a horrendous catch.
So then on the next try youngrip it even tighter and get worse results.

 

[Grey Darrah]

Using a shear scrape with light touch, a few passes and a sharp blade got it. It's not as glass smooth as a bevel riding push cut in the proper direction, but it's pretty close. Thanks for all your suggestions and help.

Grey

 

[John Turpin]

Ask who has had an Ellsworth class.

I have an Ellsworth DVD and he does a good job explaining it. I now use the shear cut at some point in every piece.

 

[Bill Boehme]

Just to be clear on terminology, a shear scrape isn't the same thing as a shear cut.

 

[Allan Moore]

For me box elder just gets to a point where no matter how sharp the gouge or how fine a burr on the scraper there just is no cut to get out all the torn grain. I use the old stand by putting sanding sealer on and make one final cut or shear scrape ,and then just break out sand paper. I find that I hit a point trying to get rid of torn grain with a gouge or scraper is just not productive , hit the inevitable and power sand. I do believe each piece of wood is an individual and you just have to adjust tactics. Love box elder colors , hate the grain.

 

[Grey Darrah]

For me box elder just gets to a point where no matter how sharp the gouge or how fine a burr on the scraper there just is no cut to get out all the torn grain. I use the old stand by putting sanding sealer on and make one final cut or shear scrape ,and then just break out sand paper. I find that I hit a point trying to get rid of torn grain with a gouge or scraper is just not productive , hit the inevitable and power sand. I do believe each piece of wood is an individual and you just have to adjust tactics. Love box elder colors , hate the grain.

It came out pretty good with a sharp tool and light shear scrapes. Here's a pic of it right off the lathe, still pretty wet with no sanding yet done. It's about 9.5" wide by 8.5" tall.

Grey