Sharpening Bowl Gouge with Elsworth Grind

[Dana Berenson]

I've got the Oneway Wolverine Grinding Jig and the Vari-Grind Jig to sharpen my bowl gouges. I find that during the sharpening process, the gouge sometimes slides off the sharpening stone, especially when I am switching hands to switch sides. Does anyone have a strategy or a jig that allows you to keep the gouge still?

Also, does anyone know why the part of the Vari-Grind Jig that rests on the Wolverine is not rounded all the way around?

Thanks!

[Jim Becker]

You can approximate the Ellsworth grind using the VariGrind jig, but not exactly duplicate it. This has to do with the physical location of the pivot point in relationship to the angle of the jig. The solution is to either use the Ellsworth jig as designed, use the Ellsworth jig on the Wolverine arm with a block in the saddle, so to speak, that raises the pivot point to the correct geometry, or buy the after market arm that is designed to position the Ellsworth jig at the right point. Note that vertical location relative to the wheel centerpoint and distance of the pivot point from the wheel surface (which changes postion as the wheel wears) are critical to maintaining a consistent grind.

As to the rotation for a side grind, you have to develop a light touch and when you switch sides/hands, you have to disengage the tool from the stone so you don't over grind in one place. This takes practice... ;)

[Cyril Griesbach]

The after market arm that Jim mentions comes from Don Geiger and is called the Geiger Solution.

http://www.dongeiger.com/index.html

However, the Ellsworth Grind can be very closely approximated by extending the tool about 3" out of the Vari-Grind Jig. Just be sure to adjust it according to Oneway's instructions for the Vari-Grind but with the additional extension.

[robert hainstock]

While I have a differant jig,(PSI) It works the same way and I have used Steve Sclumpf's wolverine so I am curious as to what the issue is for you.
both jogs performed well for the bowl gauge grind you rtefer to. ????
Bob

[Reed Gray]

I start by grinding the wing on one side first, then rotate the gouge up to the tip. Then do the other side. I don't make one sweep from one side, across the tip, and then to the other side. Can't bend my arms enough to do that. Also, I will eyeball the profile constantly. It seems that I still will grind more off one side than the other, or not go all the way to the tip, or rotate through the tip too much from both sides so that the tip gets square.
robo hippy

[David Walser]

Dana,

The Vari-Grind will do what you want it to, you just need to learn how to use the jig properly to produce consistent results. Find a copy of Lyle Jamieson's DVD, Bowl Basics the Easy Way, and watch his explanation of how to use a Vari-Grind style jig to sharpen bowl gouges. He shows you how to hold the jig -- which hand to use, how to stand, where your head should be, where you should be looking, etc. He also shows you how to sharpen one wing of the gouge, then the other wing, and then to blend the nose of the gouge into the two wings. (He does not recommend you try to grind the entire bevel in one motion. You'll often end up with the problem you describe.) He shows you how to adjust the jig to produce the types of grind you want (including the Elsworth Grind). He gives tips on how to quickly and accurately set the jig up time after time. He discusses how to tune up your grinder, what kind of wheels to use, etc. He also discusses the various jigs on the market and points out the good and bad points of each. In short, it is absolutely the best video I've ever seen on using a dry grinder to sharpen a bowl gouge. The instruction on sharpening alone is well worth the $40 cost of the DVD. (It's even better if you can borrow it from someone. Free's always nice.)

I use a Tormek to sharpen my turning tools and still learned a lot from Lyle's presentation.

Here's a link to CSUSA's description of the video: http://www.woodturnerscatalog.com/store/Videos___Techniques___Bowl_Basics_the_Easy_Way___j amieson_bowl_basics?Args=

The video is available from a number of retailers.

[Bob Hovde]

You can approximate the Ellsworth grind using the VariGrind jig, but not exactly duplicate it. This has to do with the physical location of the pivot point in relationship to the angle of the jig. The solution is to either use the Ellsworth jig as designed, use the Ellsworth jig on the Wolverine arm with a block in the saddle, so to speak, that raises the pivot point to the correct geometry, or buy the after market arm that is designed to position the Ellsworth jig at the right point. Note that vertical location relative to the wheel centerpoint and distance of the pivot point from the wheel surface (which changes postion as the wheel wears) are critical to maintaining a consistent grind.

As to the rotation for a side grind, you have to develop a light touch and when you switch sides/hands, you have to disengage the tool from the stone so you don't over grind in one place. This takes practice... ;)

Jim,

I saw David at a turning symposium in Nashville and he showed me a way to use his jig on the Woverine without the block. He extends the gouge out of the jig the length of the saddle in the Woverine arm and then adjusts the arm until the face of the grind is flat on the wheel surface. I do it that way now and get a good grind - slightly longer wings than before. I second your remark about a light touch.

Bob

[Jim Becker]

Bob, thanks for the comments about your conversation with David. It's good to know that he's talking about a way for folks to use the Wolverine without modifications. Making the block was easy, but it was an extra step and had to be removed to use the arm for other tool sharpening tasks. I used thumb screws to make that functional when I was using the add-on block. The Geiger arm took its place now in my shop. Maintaining a consistent Ellsworth grind is important to me because I use the 3 gouges I have for 95% of my turning work...

[Tom Godley]

It took me a while to learn to do it correctly using all the jigs!!


I found that it works best if you learn to do the grind in one motion. This produces a balanced grind without flat sides or a pointed tip.

I am sure that David can do the grind freehand if need be - but everytime I have seen him sharpen he uses the guide.

[Terry Stellman]

Bob,

Could you post a picture of the setup you are talking about? I'm having a problem picturing it in my tiny mind. Thanks.

Terry



Jim,

I saw David at a turning symposium in Nashville and he showed me a way to use his jig on the Woverine without the block. He extends the gouge out of the jig the length of the saddle in the Woverine arm and then adjusts the arm until the face of the grind is flat on the wheel surface. I do it that way now and get a good grind - slightly longer wings than before. I second your remark about a light touch.
Bob

[Bernie Weishapl]

I do like Reed does. I do one wing bringing it up to the middle. Then take it away and switch hands to do the other side. Don't leave your grinder on the middle of the gouge as that takes a light touch.

[Andy Hoyt]

Don't stand in front of the grinder.

That's why you have to switch hands.

Stand off the to one side or the other.

[Gary Herrmann]

I recently picked up Don's jig. Following the directions I was able to duplicate the grind first try as evidenced by all the marker being removed from the the existing bevel. It's a good investment.

[Dana Berenson]

As usual, everyone has some very helpful and valuable insight. Thanks so much for sharing your perspectives here!

You all ROCK!