Do Angles Count?

[Dan Forman]

Wally --- I haven't tried this at the end of the lathe yet, but to keep tucked, and work all the way around the bowl in one cut would seem to require some pretty fancy footwork in order to maintain a ridge/dip free surface, whereas using a long handle and working away from the body at the beginning of the cut will prevent you from having to move the feet. Each would seem to present different challenges to a single, smooth, continuous cut from foot to rim.

Dan

[Hayes Rutherford]

Dan, now that you have the push cut down you can combine the two methods and in one motion. form the chuck spigot, pull cut the flat spot for the chuck jaws, pull cut a base , then start to pull the bottom curvature of your vessel, then roll the gouge and swing the handle around and go into the push cut and finish the outside curvature. You are actually scraping when you start the cut but that gets you around the problem of starting a push cut at the base.

[robert baccus]

I finally caught on here. You guys were talking about the tailstock getting in the way of your handle and I couldn't get my head around that. No wonder--that gouge cuts both ways you know. I always cut toward the"holding", and downhill if possible. You got boocoo room if you cut the outside or inside towards the bottom. I thought this was standard practice but maybe not. Wally, I remember those days--I think I bought the first DB gouge in Texas. I smiled for a week after that yeah. Suddenly I had to use a rake and shovel in my shop. Dan, try a super sharp 3/8 DB gouge on your final cuts with the bevel rubbing--light, fast rpm cut???

[Reed Gray]

Dan,
For your push cut (photo 1) you are using a 'traditional' gouge, which is ground very similar to a spindle roughing gouge. Rolled onto its side, you get a high angle shear cut and a long 'sweet spot'. This is a different cut than if you use the 40/40 gouge rolled onto its side.

For your pull cut (photo 2) if you try to cut with the flutes pointing up, you are really doing a scrape cut, and that one would be very grabby. For the pull cut, you need to drop the handle, and roll the flutes over to 90 degrees, or sideways. That way you are getting a bevel rubbing cut and a fairly high shear angle. If you roll it over some more, you have a 'shear scrape' as in high angle shear cut with no bevel rub.

robo hippy

[paul vechart]

"Warning - this is not the same cut as Lyle Jamieson describes when he talks about push cut in his Youtube video. "

Dan you mensioned above about Lyle Jamieson's push cut not being the same as the push cut you are talking about. I watched Lyle's u-tube videos and would like you to tell us the difference in the push cuts if possible. I just bought a new Sorby bowl gouge...it came with a 45° bevel. I used the push cut on the outside of the bowl and it really does leave a very smooth finish. Before that I was using an Ellsworth gouge with a 60° bevel angle and the finish was not as good. I know they were two different type gouges but maybe the 45° bevel is that much better than the 60°. Good thread going here!

[Dan Forman]

Dan,
For your push cut (photo 1) you are using a 'traditional' gouge, which is ground very similar to a spindle roughing gouge. Rolled onto its side, you get a high angle shear cut and a long 'sweet spot'. This is a different cut than if you use the 40/40 gouge rolled onto its side.

For your pull cut (photo 2) if you try to cut with the flutes pointing up, you are really doing a scrape cut, and that one would be very grabby. For the pull cut, you need to drop the handle, and roll the flutes over to 90 degrees, or sideways. That way you are getting a bevel rubbing cut and a fairly high shear angle. If you roll it over some more, you have a 'shear scrape' as in high angle shear cut with no bevel rub.

robo hippy

Reed --- It's the same gouge in both pictures, a 40/40 grind - it only looks like a traditional gouge in the push cut photo because of the angle of the photo - the nose of the tool seems to be foreshortened, but it's still there. I just wanted to show how the wood was being cut, and that was the best angle to show it, but you're right, it does look like a traditional grind.

In the pull cut picture, I just was trying to show how it would cut the wood coming down on the edge from above, more than the push cut takes from in font of it. Hope that makes sense. Because I took the pictures one right after the other, I just laid the gouge on the gap left from the push cut. Had I actually done a pull cut, then showed the gouge in the position that cut was made in, it would have looked a little different, rolled over on it's side a little more to rub the bevel, but I figured everyone would already know that one. Hope that clears up the confusion.

Dan

[Dan Forman]

I finally caught on here. You guys were talking about the tailstock getting in the way of your handle and I couldn't get my head around that. No wonder--that gouge cuts both ways you know. I always cut toward the"holding", and downhill if possible. You got boocoo room if you cut the outside or inside towards the bottom. I thought this was standard practice but maybe not. Wally, I remember those days--I think I bought the first DB gouge in Texas. I smiled for a week after that yeah. Suddenly I had to use a rake and shovel in my shop. Dan, try a super sharp 3/8 DB gouge on your final cuts with the bevel rubbing--light, fast rpm cut???

DB gouge = dedicated bowl gouge???

I get much better surface working out from the foot, than working in from the rim. I will use the latter sometimes for gross shaping, but can still get tearout from it. I was wondering why you couldn't see the trouble, it was pretty obvious to me.

I use an American (D-Way)1/2 gouge for the final cut, which would be the same as a 3/8" English gouge. I do speed up the lathe for it, but sometimes the roughing cuts have a better surface, as I have nowhere near mastered this yet. I am steadily improving though.

Dan

[Dan Forman]

Dan, now that you have the push cut down you can combine the two methods and in one motion. form the chuck spigot, pull cut the flat spot for the chuck jaws, pull cut a base , then start to pull the bottom curvature of your vessel, then roll the gouge and swing the handle around and go into the push cut and finish the outside curvature. You are actually scraping when you start the cut but that gets you around the problem of starting a push cut at the base.

Hayes --- I don't really "have it down" yet, but working on it. The attraction of doing it all in one go is not having the blend the two cuts, though that will probably happen on occasion. and can always be done if circumstances demand. I am reasonably flexible that way, but still trying to get the pure approach down too. Kind of like learning the melody before improvising, going back to musical analogies.

Dan

[Dan Forman]

"Warning - this is not the same cut as Lyle Jamieson describes when he talks about push cut in his Youtube video. "

Dan you mensioned above about Lyle Jamieson's push cut not being the same as the push cut you are talking about. I watched Lyle's u-tube videos and would like you to tell us the difference in the push cuts if possible. I just bought a new Sorby bowl gouge...it came with a 45° bevel. I used the push cut on the outside of the bowl and it really does leave a very smooth finish. Before that I was using an Ellsworth gouge with a 60° bevel angle and the finish was not as good. I know they were two different type gouges but maybe the 45° bevel is that much better than the 60°. Good thread going here!

Paul --- Stuart defines a push cut as one in which all of the force actually directing the cut or path of the gouge comes from the right hand pushing the gouge from the foot of the bowl to the rim. The left hand only holds to tool on the rest, it doesn't guide it in any other way. If you look at Lyle's cut, (for the outside of the bowl) he is pulling the tool with his left hand, which by Stuart's definition would be a pull cut. . This is only for the outside of the bowl, there is no pull cut on the inside, only push.

Stuart's version of the push cut is shown below. You stand back behind the bowl, the gouge is primarily guided by the right hand pushing out to the rim, the left hand only holds the tool down on the rest, not pushing into the wood, which would cause the tool to start bouncing. If you feel the bounce, you know you are doing it wrong. Thats the instant feedback I was talking about earlier. The shaving is primarily taken by the nose, not the wings, and the cut is into side (face) grain, no end grain. The pull cut alternates cutting side and end grain. Tearout often results when cutting end grain.

The pics I posted this afternoon were closeups, and didn't show the operator, so I hope this one will clear that up. It's awfully hard to show everything you want to when using delayed shutter, so I wasn't able to get the nose of the tool in the picture. By the way, I don't claim to be at all expert about this, just going on what I learned from Ashley Harwood, who was a student of Stuart's, and from the video :Two Ways to Turn a Bowl, by Stuart Batty and Mike Mahoney. The video is highly recommended, and explains all of this in depth. For all I know, Lyle's could be considered a push cut, but doesn't seem to fit Stuart's definition. If you look at the way Lyle cuts the inside though, that does fit: left hand pushing the tool down on to the rest, right hand guiding the direction of the cut.



Dan

[Dan Forman]

Is it just me, or is the Creek a little goofy tonight? Anyway, this was a double post, so please ignore.

Dam

[Reed Gray]

I did a push cut for years and used both hands till I saw Chris Stott at a demo for our club. He started a cut on the inside of a bowl, dropped his left hand, turned around and started chatting with our club. Huge eye opener. The thing with the 2 handed cut is I don't think you 'feel' the wood like you do when the left hand only rests on the shaft. We all know that bump that happens, both inside and outside the bowl when the bowl goes out of round. Use less pressure on the drive hand, and less 'grip', and most of that bump smooths out.

robo hippy

[robert baccus]

Sorry--I was referring to a US true 3/8 DB--deep bowl gouge. I find better support for the gouge(especially on thin wood--less chatter) cutting toward the hold and downhill if possible. For one thing I am not in a contortion position dodging the tailstock. If I do my part I get perfect cuts and if I can anyone can. Like Wally I bought a DB gouge before I knew what it was supposed to do and was purely self taught. I'm about to get over that handicap but I can say I know all the wrong ways to cut wood. Love this thread--how about another DAn.

[Dan Forman]

Robert --- Stuart has some very interesting bowl gouges coming out in the next couple of months - parabolic flute, and laminated with 10V on top for a long lasting edge. They are milled from beam shaped stock (higher than wide) for extra support. Ashley had a couple of them, and I'm going to pick some up when they are ready. Ashley recommends a parabolic (eliptical) flute, in between a U and a V, but with continually curving sides rather than straight like a V. She says a U has too wide of a nose for a 40/40 grind to work well, would be too aggressive. The D-Way gouges that I have are closer to a U than a V, but have the straight sides of a V. I think a slightly narrower nose would be easier to control, and parabolics are easier to blend the edge when sharpening. For reference Sorby bowl gouges have a parabolic flute. Here is a link to the Batty gouges: http://www.woodturning.org/sbw/wp-co...o-consumer.pdf The usual disclaimer, I have no connection to Stuart Batty.

I guess I'll have to try the rim to foot cut, but like I said before, I often get tearout in that direction when initially shaping a roughout.

Dan

[Grant Wilkinson]

This is great information, but some of it leaves me confused. Robo, you said that the Batty grind cannot be achieved with a jig. I don't understand why not. As I read Stuart's picture, you could place a gouge with the flute flat on your grinding platform, set at 40 degrees, and grind the 40 degree sweep. Then, you could place the gouge flute up on your platform and grind the nose to 40 degrees. Then, using a wolverine/varigrind or some other similar jig, you could turn the bevel on the wings. You would set the length of the wolverine by placing the gouge in the varigrind, and the varigrind in the pocket of the wolverine, then moving the wolverine "bar" until the nose angle that you ground on the platform lined up with the wheel. I appreciate that the angle on the wings would vary depending on where you had set the arm on the varigrind, but the 40/40 would be intact. I don't see anywhere in Stuart's pic where he talks about the ideal angle for the wing, only the angle for the sweep.

If I am wrong, and that's entirely possible, I would be grateful if someone could explain why. I'm not arguing the merits of the 40/40 over the 45/45 or any other angle, merely trying to understand why they cannot be achieved with a jig.

[Reed Gray]

I am not totally clear on that either, one would think it was possible, but Stuart and others who use this grind claim that it is so. Mostly I don't think the gouge rolls properly to the side when you attempt this grind. I don't even have a gouge jig any more, so can't attempt to grind it both ways and see what the actual difference is. You grind flutes down at 40 degrees, roll it over, and grind away the flat. There is commonly a line scribed into the platform so you know where 40 degrees is.

robo hippy