Ellsworth Similar Grind

[Chris Barnett]

Grinding the Sorby 1/2-inch (.639" dia.) to look like the profile of the Ellsworth HSS 5/8-inch (.634" dia), the result was close but the wing face tapered proportionally through it's length on the Ellsworth original grind, whereas the Sorby wing face was wide to the end. The lower face edge on the Ellsworth appears to be a straight line. Are the non-tapering wide wings shown on the ground Sorby typical of what folks obtain when they grind a gouge with a profile similar to the Sorby? The Sorby's groove width is larger but the Ellsworth groove is slightly deeper. Perhaps the wings should have been ground more.IMG_3642.jpg
Is there a benefit to continue developing the profile to be indentical to the Ellsworth, and what should be changed to achieve that tapered face? The grinding setup was a Oneway grinding station with Varigrind using pivot point 7 inches from wheel face and 4 inches below wheel center. Varigrind angle was set to match the heel angle of the Ellsworth gouge.

[Paul Heely]

I think that you would need to change the angle of the arm on the vari-grind to try and change the taper on the wing. Try loosenign the arm and with the gouge in the jig hold it to the wheel as if grinding the wing. As you change the angle of the arm you should be able to visualize how the wing taper would change. As to any benefit, practically speaking, I'm not sure that the way I cut it would make any difference. The only time I'm using the part of the wing where it tapers down is if I'm shear scraping.

Paul

[Steve Kubien]

I am not an expert but I think once you change the geometry of the flute (the Sorby is different than the other one, right), then there is little chance of the wings appearing the same.

As for whether it matters, it depends. The Ellsworth grind is a nice general purpose grind. I am not sure it does any one thing exceptionally well. Hmmm, maybe shear scraping and getting into the bowl of a bowl. I have recently started grinding my bowl gouges between 45 and 50 degrees and I have been a lot happier overall. Way faster at roughing out and a much nicer finishing cut too.

But, that's just me. Ask 3 turners how to grind a bowl gouge and you will get 15 answers!

[Jamie Donaldson]

It doesn't really matter whose grind you are trying to copy, but which one works better for you. I could hardly make sense of your question, but I use the profile similar to the bottom gouge in your example with a bevel angle of 60 degrees, same as the Ellsworth spec. I like the long straight wings on my big gouges for leveling the almost flat surfaces of my winged bowls with a shear/scraping cut, allowing me to start sanding at 220.

[David E Keller]

Like Jamie, I'm not sure I entirely understand the question... My gouges are ground very similar to the gouge at the bottom on your photo. I think most of us find a grind that we like and then stick with it, but I don't think there's a right or wrong.

On the varigrind, I typically adjust the length of the arm(the pocket) to match the bevel angle at the tip of the gouge and use the leg adjustment on the actual jig to change the wing profile. I fiddled with the jig adjustment until I found something that I liked. If you'll look at the Thompson tool site, there's a photo of the varigrind on the sharpening page, and I used that for my starting point on adjusting the jig.

[Bill Walsh]

Chris, I've set my vari-grind jig up the same as David using Doug Thompson's easy to follow instructions from his web site. Boils down to setting the leg about half way on the vari-grind then just move the arm in and out. I grind angles between 45 and 60 degrees for most tools. I have a complete set of Raptor set up gauges. They make it so easy to touch up a detail gouge with a 30 degree angle then switch back to say a 55 degree bowl gouge. No black marker and fooling around with the vee arm. Just takes seconds to adjust. Dead on every time... I see no benifit grinding away tool steel if your happy with the way the tool cuts. Different tool makers use different shaped flutes so its hard to grind the tool to look exactly the same. Keep the wings flat or with a slight convex curve, never concave. I try to keep them flat so the tool can be used to shear scrap the outside of the bowl.

[Bernie Weishapl]

I generally run a bevel of around 55* and my wings are cut back a little further than the bottom gouge. I do this to use like Jamie does and also with the longer wings I can shear scrap the outside of a bowl to start sanding at around 180 grit. I just experimented until I hit on something I liked. Any gouge I get it in is sharpened the same way. It works for me.

[Dennis Ford]

I see two differences in the gouges pictured:
a) slightly different flute shape (negligible effect on how it cuts)
b) different cutting angle on the wings (big difference on how it cuts IF you cut with the wing). The Ellsworth grind is easier to control when cutting with the wings. The other grind pictured has a smaller margin of error when cutting with the wings.

[John Keeton]

Without a straight on view from the point of the gouge, it is difficult to say for certain, but it would appear the two gouges have an entirely different "cross-section" and regardless of how you attempt to duplicate the appearance, it will not be possible. Using the same grinding setup for both will always result in a different appearance of the ground surfaces.

I double bevel my gouges, reducing the width of the working bevel to about half or less of what comes off the grinder. That works for me, but may not for you. So much depends on the type of turning one does, and on personal technique. That is why so many different profiles and grinds are out there - so we can try them all!!! I think I want a couple more gouges!!! And, I think I will probably do that while at the OVWG Symposium!!

[Chris Barnett]

The Ellsworth is the top gouge (used but never sharpened), the lower is the Sorby, and they both have the same bevel angle because the Varigrind was set from the Ellsworth bevel. The only difference is the wing profile....the face width of the side of the Ellsworth gouge tapers to a point at the rear and the Sorby face ends as a semicircle.

I was attempting to duplicate the Ellsworth since it seemed to shear cut the outside of the bowl so smoothly, but I did not want to sharpen and thus grind away the Ellsworth profile until I had that exact shape duplicated on the Sorby.

Info found by searching states to set the pivot point 7 inches from the face of the wheel and 4 inches below the center; I have moved the rest in and out and changed the angle of the Varigrind but cannot get the face of the bevel to look like the Ellsworth. I have since varied the angle and the distance from the wheel (but not the height to wheel centerline) and cannot get the tapered face like the Ellsworth.

The question was.....can the tapered face on the Ellsworth be duplicated on the Sorby or other gouge? I will assume the answer is no, because the grooves are different. The other question asked basically is it worth exactly duplicating the Ellsworth profile. Again, apparently no, since it is just a good all around decent shape. I did not want to waste material trying to do what cannot be done, but I did want to find the grinding setup that would repeat the Ellsworth profile....on the Ellsworth before I ground that profile away.

Need to replace my wheels now....when trying to get the tapered face with the Varigrind jig leaned way over, caught jig between the wheel and the housing, chipped the wheel and spun the other wheel off which careened across the shop, coming to rest under the lathe...also badly chipped. The wheel covers were both removed to get the wheel centerlines to pivot points...big mistake.

Thanks for your help, and wish I could have been clearer in my previous questions.

[Bob Bergstrom]

The Elsworth is a deep fluted "V" shaped gouge. Most Sorby's have more of a "U" shape in the bottom of the flute. They will present different profiles even off the same jig. You pay extra money for that profile on the Elsworth. Even the standard Crown Pro bowl gouge is different than the Elsworth and $10 cheaper (more like the Sorby). The tip of the Elsworth is more pointed and works well on a push cut down the outside and inside of the bowl. A Sorby is better ground with high flutes for cutting on the high flutes while the tip can be used to cut across the bottom of a bowl.

[Gary Kman]

Have been lurking for a while and have a question before I can put any of this information to use. The information that I have collected from FWW and Dave Ellsworth's book and have tried to apply centers on two principals. Keep the bevel rubbing to achieve a shearing cut. This is best illistrated by making a linear test cut on a flat board. Pushing the gouge along a flat board like a plane to make a shaving. It is immediately obvious the angle needed to cut without digging in. Second, roll the gouge while advancing across the entire pass to use all of the edge. That is - when the tool becomes dull, the entire sharpened edge will be dull.

Is that how you guys are turning?

[Jamie Donaldson]

You were doing fine with the bevel rubbing/shearing cut in the first part Gary, but when you started to roll the gouge "to use all of the edge" is when you quickly ran into what we call a catch!

[Mark Levitski]

Yes, Gary, that's right, though your use of "rolling the gouge" could be misleading. I'm sure you meant rolling it in the same plane along the axis of the handle to engage more of the edge whilst the bevel rubs to create a beefier cut. Jamie's correct: if you rolled the edge as if rolling the handle clockwise or counterclockwise on its axis, you'd set it up for a catch. The edge comes off the support of the bevel. Merely engaging more of the cutting edge while the bevel is rubbing is a normal part of turning. One chooses how agressive a cut to make depending on the cpapcity of your lathe and the finish that results.

I have several bowl gouges with different flute profiles. Don't get caught up and bogged down in too much detail and overthink the basics. In my experience, there are only subtle differences to be found beyond the more fundamental gouge techniques and sharp tools. Just keep turning a lot and find out what works best for you. That's what led the Ellsworths and the Grumbines to become who they are as teachers of technique.

[Gary Kman]

I guess I'm thinking about using a bowl gouge like a roughing gouge. I was just starting and doing ok sliding a square ended roughing gouge back and forth making squares round when I went to a gathering of some kind that had a turner named Harry Kloppel (I think). Anyway he had a wood bed steam powered lathe with fairly substantial HP the way chips were flying. He had a gouge that looked like a piece of 2" plumbing pipe split in half and sharpened (Size and scale anyway). Perfectly square on the end. He rolled (twisted) as he cut along the spindle using every bit of the sharpened edge from the left edge on the left end the right edge on the right end. I adopted the technique roughing. Smooth, natural, easy and getting all the use out of a sharpening. I'd like to improve my final shaping and with a smooth finish if possible (certainly no pulled grain from hard scraping). I get the "lumpies", ridges and valleys on areas I want a sweeping curve on the inside or outside of bowls and plates.