An easy way to rough turn bowls

[hockenbery]

Many turners don’t enjoy roughing. They get beat up from pointing tools the wrong way and loosing control of the cut.
Many years ago Christian Burchard showed me a very effective pleasant to use cut with the side ground gouge.
Gouge needs around a 60 degree front bevel.

He called it the A frame cut. Two straight arms with the tool as the cross piece.
Rotating the hips cuts a smooth cove.
Sneak up on the first cut swing an arc through air. Move the tool forward a 1/4” between each test cut until you cut.
A 1/4” cut every pass is a good starting point. With practice you can cut the full length of the wing.
1/2-3/4” cuts are easy and the tool does the work.

I put together a 3minute video from a couple of demos that shows the mechanics of the cut.
Please add you techniques or comments

A Frame Roughing Cut -

View: https://www.youtube.com/watch?v=qYuA5ywiRFo

 

[Kent Reisdorph]

Interesting. Al, what grind is on that bowl gouge?

 

[hockenbery]

Interesting. Al, what grind is on that bowl gouge?

Thanks for asking. I use an Ellsworth grind. It has a 60 degree front bevel.
I grind my wing a little longer.
That front bevel is kind of important. I added that to the post.

The 40/40 won’t do this cut well if at all because the handle has to be way to the right to ride the bevel.
The handle probably hits the tailstock with a 40/40

A Michelson grind would work well. You could use any sideground gouge with a front bevel around 60 degrees.
Probably work with 70-55 degree front bevel.

 

[Kent Reisdorph]

Awesome. My main gouges are both 55 degree(ish) Ellsworth grinds. At least they were 55 degrees when I made them a few months ago. I'll have to check and see where they are now.

 

[Doug Freeman]

I learned Ellsworth's roughing method, which is very similar, with one main difference - hold the tool horizontal, flute at 45° or greater (rotating the edge closed reduces how much edge is exposed to the wood). When the tool handle is lowered, the force of the wood against the edge creates a horizontal force "vector" (physics term) that pushes the tool off the tool rest, which the turner must counter. The steeper the handle, and the heavier the cut, the higher the horizontal force vector. With the tool horizontal, all the force from the cut goes into the tool rest. It is also not important to have the bevel rubbing - it's a roughing cut to get to "round", where a bevel rubbing cut can then be used to smooth things out. Any bevel angle can be used - I use a 40° long wing edge shape for roughing. A 40/40 can be used as well. The sharper edge slices through the wood with less force vs ~60°. A higher angle, ~60°, is required to get in around the foot with a push cut once round, or a pull cut with the wing can be used. Getting rid of that horizontal force vector makes a huge difference.

Until the work is round, it's always an interrupted cut. The faster the work can be spun, the less "free air time" the tool edge has to change position. So, spinning faster (up to your, and the lathe's, tolerance) makes it go smoother. Once up to ~ 600 rpm and up cutting starts to smooth out.

Ellsworth describes and demonstrates, stating at about 5 min mark. Also described in his book:

View: https://youtu.be/wGupR8Lt9E0?si=-bN2qJbVC7aH36Tq

 

[Darryn Achall]

My big gouges are ground 60 to 62 degrees with swept back wings. This A frame cut works great for roughing. I usually don't bother to shape blanks with a saw. Mount an odd shaped chunk with bark and all on the lathe and use this method to fairly quickly rough it to round in the general shape I'm after.

 

[Bill Alston]

I like the traditional Japanese style of bowl turning. The blank is rough turned mechanically on what often looks like a large engine lathe. After seasoning it’s then finish turned on a traditional lathe with their iconic tools made from carbon steel.

 

[Tom De Winter]

It looks like David is getting quite a bit of bouncing at the handle end. I reviewed Al's video to see if he was also getting this but didn't see a shot of the handle end. Though it looked like the gouge is more stable with his approach.

I can't wait to get to the shop to try out both.

Thanks for sharing.

 

[Mark Fairchild]

It looks like David is getting quite a bit of bouncing at the handle end. I reviewed Al's video to see if he was also getting this but didn't see a shot of the handle end. Though it looked like the gouge is more stable with his approach.

I can't wait to get to the shop to try out both.

Thanks for sharing.

Tom, I have used Ellsworths method for A while. Once I tried the above mentioned method I won’t go back. Everyone has their own method they like which suits their style. For me, Al’s method is much smoother as you noticed.

 

[robo hippy]

Well, you know me, scrapers rule for roughing. I always rough bowls on a short bed lathe. Sliding headstock or pivoting headstock, and a 1 inch Big Ugly tool. After a number of years of doing this, gouges are just too slow.

robo hippy

 

[Bill Alston]

Well, you know me, scrapers rule for roughing. I always rough bowls on a short bed lathe. Sliding headstock or pivoting headstock, and a 1 inch Big Ugly tool. After a number of years of doing this, gouges are just too slow.

robo hippy

Reed, isn’t this the way it was done years ago, before the advent of the bowl gouge?

 

[hockenbery]

After a number of years of doing this, gouges are just too slow.

You are quite skilled with the scraper. I did my first bowls in the 1970s with scrapers. Then found the long and strong gouges.
Then in the 90s the side ground gouge.

I find the gouge much easier on the body. For me using a scraper is hard work and if I get a little over the tool rest I have to use downward pressure on the handle to keep the scraper on center.

When I use the gouge it does all the work. I can hold it finger tight to guide it. I also get a cleaner surface cutting.

What works for me won’t work for everyone.

 

[robo hippy]

As I say in my Scary Scrapers video, so many people think using a very thick and wide scraper is the way to go. I don't agree at all, and never use any more than 1 inch wide or 5/16 thick. Getting too much metal into the wood at one time is a big problem. To me, this is why the carbide scrapers are so popular. They are all smaller which makes them easier to control. The down side to using scrapers for all the cutting is that you still need gouge skills. I am trying to learn to use scrapers now...... If I had turned as many spindles as I had bowls, I would be an expert with skews now....

robo hippy

 

[Doug Freeman]

so many people think using a very thick and wide scraper is the way to go. I don't agree at all, and never use any more than 1 inch wide or 5/16 thick.

I agree for roughing/ heavy to light cuts, but for using them for shear scraping, a 1-1/2” with a V works well.

 

[robo hippy]

I had to go check..... My spear point and round nose are both 1 5/16. My ) one is 1 inch. For reasons unknown to me, the M42 goes from 1/4 to 5/32, and then to 1/2 inch. My ) one is 5/16, and a Thompson.

robo hippy

 

[Bill Alston]

What included angle do you use for your scrapers? I used to use 80° but have more recently found 70° or even 65° works very nicely for finishing cuts. I expect this sort of angle may not be durable enough for roughing though?

 

[Dave Fritz]

Thank you Al. I like too that it keeps you out of the line of fire.

 

[robo hippy]

My scraper angles are at 65 degrees. My NRSs are 25/55, which on my robo rest are 60 and 30. I am finding that some times the grinder burr works best rather than the burnished burr on M42 and V10. I have been turning some bay laurel/myrtle, and on one bowl, the NRS leaves a beautiful surface, and on the next, not so good.... You just never know. With this myrtle, I will have to start sanding at 80 grit. No way around it....

robo hippy

 

[Dennis Weiner]

Thanks for asking. I use an Ellsworth grind. It has a 60 degree front bevel.
I grind my wing a little longer.
That front bevel is kind of important. I added that to the post.

The 40/40 won’t do this cut well if at all because the handle has to be way to the right to ride the bevel.
The handle probably hits the tailstock with a 40/40

A Michelson grind would work well. You could use any sideground gouge with a front bevel around 60 degrees.
Probably work with 70-55 degree front bevel.

Regarding 40/40 won't do this cut well...etc.
Al, the 40/40 is not used by Batty to cut a Rough bowl blank into round using a drive center and live center. So yes, you're right in your video. The Tailstock may get in the way of executing with a 40/40. However, Batty first flattens the top, makes a tenon, and places it on a chuck. The tailstock is not needed. While on the chuck, you can see him effortlessly bring the bowl to round with his push starting around 29-30 minutes into this recent YouTube: You do not get beat-up at all using his method as well as the Aframe method.

View: https://youtu.be/dw2bMwUpOZ4?si=jj1foEdNFlnASXVa&t=1774


I used the Ellsworth for 18 years until I found the 40/40 method. Old habits Die hard.

 

[robo hippy]

I don't find the 40/40 to get in the way when I do use them for roughing any bowls, which I do some times. I generally don't use a tailstock when turning bowls. For the bowl he is turning, you need the tailstock engaged for that particular lathe. That nose cone puts the bowl mounting spot several inches out farther than on the Vicmark lathes. This will cause vibration on the bowl blank when turning. The vibration goes away when the tailstock is engaged. I also stopped using the swept back gouges after a work shop with Stuart and Allan Batty and I learned the 40/40 grind. It does work better/more efficiently. If you can only afford one gouge, then the swept back gouges do a bit of everything.

robo hippy