Bowl gouges

[loberg]

I have been to a fellow woodturners house for lessons. He has gouges that have a deep flute but the bevel is very steep (high angle). He said these were for turning the inside bottom of bowls. What is the name for this type of gouge and where is a good place to get one. Thanks

 

[GeorgeH]

Well, the Ellsworth grind (fingernail grind) is typically 45 - 60 degrees. But I'm not sure what you mean by "steep" so, if your reference is intended to describe a different axis, it could be what's known as an "Irish" grind which runs about 22 degrees +/-. The traditional bowl gouge (I don't know anyone who uses one) is ground at about 45 degrees (some set it at about 50 degrees).

http://www.turningwood.com/fingernail1.htm

http://www.woodturnerscatalog.com/s...=&imgsrc=/products/large/htt-kryo-irish_l.jpg

http://www.woodcentral.com/newforum/grinds.shtml

 

[robo hippy]

I have an old Glaser bottom of the bowl gouge. It looks similar to a spindle roughing gouge, but the edges are rounded back slightly rather than square/straight across, and the bevel is 75 to 80 degrees (no I didn't measure). On larger deeper bowls, it is impossible to get a bevel rubbing cut all the way down the sides, through the transition and across the bottom. On smaller shallower bowls, this usually isn't a problem, unless your gouge is almost worn down to the end of the flute. The tool rest gets in the way, and the rim of the bowl gets in the way (as in your gouge handle will rub on it). A 45 degree gouge can't make it. This is where the more blunt angle on the cutting edge comes in. You can ride the bevel across the bottom, while the handle points almost straight out from the bowl. No interference. I also have an old 1/2 inch gouge that I ground the same profile on, and it works fine.
robo hippy

 

[MichaelMouse]

I suppose someone, for the sake of selling gouges might make up such a name. Look at what the politically correct people are trying to do to the noble roughing gouge! I have four "bowl" gouges, which is to say deep-fluted cylindrical types, and they are all ground differently. The smaller the flute, the steeper the grind, because I expect them to work in more confined spaces.

Still, if you have a short handle and close rest, you can bottom with any fingernail grind gouge by using the 12 to 2:00 area. You get some bevel support, but you have to be very careful about the cutting edge rolling in and taking a divot. I normally stop about a half inch shy of very bottom and turn out from center using 10:00 to 12 so I don't twist out an ugly chunk. Long shafts and handles will make sure everything is in the way, so I imagine a blunt end is their way of getting the handle up off the ways or the banjo. More of a "shear scrape," if I understand that term correctly.

 

[waltben]

I believe what you saw was similar to the ones Mike Mahoney sells. One of his looks almost like a spindle roughing gouge, with close to a 90 degree grind.

 

[john lucas]

Check my article in the Winter 2008 American Woodturner. It discusses some of the different grinds and the insert by Alan Batty discusses using steeper angles on gouges to rub the bevel in deep bowls.
I have what I call a bowl bottom gouge. It is ground so the tip is about 75 degrees which is very blunt. This allows me to reach into very steep sided bowls and still turn the bottom.
On what I call dog bowls, those with a steep side and flat bottom I turn from the lip down to the transition area and then go to the center and turn out to the meet the transition area.
For those a little more advanced in their turning skills the Hunter tool is great for turning the bottom of steep bowls and hollow vessels. For southwest style vessels with a fairly flat bottom I turn from the center out. If the bottom is slopped down I turn from outside toward the center to cut downhill with the grain.

 

[Truffuls]

Ellsworth angle

Well, the Ellsworth grind (fingernail grind) is typically 45 - 60 degrees. But I'm not sure what you mean by "steep" so, if your reference is intended to describe a different axis, it could be what's known as an "Irish" grind which runs about 22 degrees +/-. The traditional bowl gouge (I don't know anyone who uses one) is ground at about 45 degrees (some set it at about 50 degrees).

Having just spent 3 wonderful days with David Ellsworth I can tell you that his gouge is 60 degrees. He also uses an 85 degree gouge to get at the bottom of a deeper bowl.

I was using the Verigrind jig for the Wolverine system on my Benjamin's Best bowl gouge. He put my gouge in his jig and re-ground it to his signature grind. I was astounded at how much better it worked. Granted my Benjamin's Best gouge has a "U" shaped flute as opposed to his parabola shaped flute so I'm not getting the exact results of his gouge, but I was amazed at how much better it performed. David's signature gouge is on my shopping list. As soon as I sell a few more items I'll be ordering it.

 

[loberg]

To sum up what I have read: The gouge is probably a bottom bowl gouge. If I can't find one then I could take a bowl gouge and grind the angle to 70-80 degrees and get basically the same unit.

My problem to overcome right now is the bottom and sides of a large and/or deep bowl. I am willing to try this gouge to help with my turning. Does this sound reasonable? I will be in the shop all next week, as I took vacation time, so I will experiment.

Again, thanks.

 

[john lucas]

To do deep sides you may need a gouge with a sharper grind, 45 to 65 degree. This is to keep the bevel rubbing while not hitting the shaft on the other side of the bowl. With an 80 degree gouge when the bevel is rubbing while you turn the sides you might hit the rim with the shaft or handle.
You are correct about the steep grind for turning the bottom. It is the same problem as mentioned above but when turning the bottom you must have a steep grind to keep from hitting the side of the bowl with the shaft of the tool.
Obviously the best way around this is to make larger shallow bowls. Then one gouge will do it all.

 

[hockenbery]

If you use a side ground gouge like the Ellsworth you can ride the bevel on a fairly deep bowl all the way to the bottom using two tricks.

first grind the heel off the front of the tool. This shortens the bevel to a 1/4 or 1/8 and inch and you won't have the heel pushing the cut deeper into the wood than wish to go. If your bowls are roughly hemispherical you can ride ride the bevel all the way to bottom. Once the heel is ground away there is much less steel on the tip so greater care must be taken with sharpening to not grind the tip too much.

The second is the shear cut on the inside of the bowl. This is an intermediate skill best acquired with someone showing you. Enter the cut with the flute pointing to the bottom of the bowl and roll the tool counter clockwise until the flute is point straight up and you are cutting just to the left nose. If you roll the tool too far Big time catch as the wood will drive onto the tool. Once you learn this cut and how to feel the sweet spot of the cut you can turn fairly tight bowls with the bevel riding.

The shear cut changes the bevel angle and allows cutting in much deeper bowl. It will yield a surface that needs much less sanding than a push cut since the curve of the tool's cutting edge at the shoulder slices through the fibers. This cut is a finish cut and should be removing 1/8 inch or less of wood.

happy turning
Al

 

[MichaelMouse]

If you use a side ground gouge like the Ellsworth you can ride the bevel on a fairly deep bowl all the way to the bottom using two tricks.

I understand the macrobevel technique from the early days of cylindrical gouges (Irish grind?), but I'm not following the counterclockwise rotation and use of the left side of the gouge. I use it from the center out, but from the rim in it seems much more stable to me to use the right side (2:00 position) if you can drop the handle far enough. Why I use fingernail ground "spindle" gouges for the task. They have short handles.

Are the opening cuts of the following similar to what you're recommending? http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=PillarSmall.flv

 

[hockenbery]

It appears to be the shear cut in the film.

I'd caution folks who look at the video to resist the temptation to knock the post off.
Even with the undercut do enough bowls and you will find an odd grain that tears out across the bowl bowl or one that breaks the chuck tenon rather than the post. I suggest turning away the post much earlier so that the finish cuts can terminate in the middle.

-Al

 

[MichaelMouse]

Well, you'd miss the whole point of the "post" by doing so. It is designed to provide tailstock support until the piece is at its very lightest and most balanced. Good protection against hooking the piece and knocking it off the chuck. As you may recall, the rear of the piece is done both green and dry with a pin chuck in the pillar. After a couple of decades of doing it, I can say it works just fine the way it is shown. You must be careful not to cut into the post with the nose of the gouge, which is why you see the opposite cut tapering in to the parting point.

The method shown produces a rough cut to be refined by the fingernail gouge used as I mentioned above.

 

[hockenbery]

I've used the center post with students and it works fine.

Like many things in turning the post is a trade-off

1. It provides extra support and some protection against ripping the bowl from its mounting in case of a catch.

2. It is also in the way of turning out the bottom.

You seem to have good tool control and I suspect you don't get catches.

I would remove the post earlier so that I could get the bottom turned out easier and I would get a better curve as by cutting it with continuous motion.

-Al

 

[MichaelMouse]

I like a continuous run as an aid to a fair curve too.

http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=CherryPeelIn.flv

Then it's center out to blend. If I cut inward to the very bottom I have a tendency to twist out the last bit because I'm behind/underneath the wood along the grain. I'd rather sand away a small "outie" than recontour an inadvertent "innie."

 

[rsser]

Those with an Ellsworth gouge or one with a similar grind might find these diagrams useful.

These are David's work and I hope he doesn't mind me posting them here.

There's a lot to the use of this grind.