Your favorite bowl gouge GRIND, and why

[Curt Fuller]

I didn't want to sidetrack Jamie Straw's thread on bowl gouges so I launched a separate one. I've seen numerous threads about favorite turning tools and I've wondered if anyone else sees this question like I do. It seems to me that a gouge is a gouge, a scraper a scraper, a skew a skew. That is until you put your favorite grind to it. Not really knowing anything about metals and metallurgy, I do know that some of my tools seem to be really easy to get a great edge on them while others are more difficult. I don't use a sharpening jig so I can't blame it on anything other than my own skills. But the one exception is I've wondered if there is a relationship between the grade of steel in the tool and the type of wheel on the grinder. I have two wheels, a 60 grit blue wheel and a 100 grit white wheel. Some tools sharpen better on one, some on the other. The visible appearance of the grind on some tools may look rougher coming off the 60 grit wheel but the edge will cut much nicer. Sometimes it's the opposite. Do the harder steels in some of the new tools require a softer wheel? When you're buying a new gouge, skew, or whatever, should you be considering how you're going to sharpen it before you make the choice?

[Nathan Hawkes]

Boy what a good thread! I've been wondering this quite a bit recently, as I just replaced the 60 grit (only marked as "medium") on my Woodcraft slow-speed grinder. I got a Norton 60 grit 8x1 wheel from www.sharpeningsupplies.com over 2 years ago, which sat in a box til now. I don't know what hardness it is, but I'm assuming it is "I" or "J", as it is softer than the vitrified Al/Ox. white stone that was supplied with the grinder. It is SOFT! I do use a Oneway vari-grind jig when sharpening everything but the traditional gouge. If I push at all beyond just keeping the tool touching the wheel, it forms a depression. However, it puts a noticeably sharper burr on the tool. All but one gouge (finishing gouge in traditional grind) are powder metal alloy of some sort or another. The burr does seem to burnish a bit faster than before, but is sharper. If I hone the burr off, it is noticeably not as sharp as before, which to me says that the harder wheel leaves a keener edge.

I'm considering purchasing an 80 grit Norton 3X wheel to replace it.
I'm hoping other responses will clear up your (and my) questions.

[Doug Thompson]

IMO - the best grind is from Johannes Michelsen which has a 45 degree nose and 45 degree wings... this is measured to the flute done freehand. This grind will get into tight places or remove tons of wood when roughing. The best part of this grind is the fact it won't catch... well there is only a small 5 degree area that could but it falls out of the cut.

Get one wheel the Norton 3X, 80 grit "K" grade, this is a very hard wheel that holds up better than anything else I've ever used.

[George Guadiane]

I have tried, but can't get Hannes' tools to work for me, at all... I have them and want to take the hat class so that I can learn to use the tools (and have a really cool hat), but not yet.

I STARTED out with a conventional old school grind and I still keep two gouges like that sharp at all times... No wings, just on the platform and rolled. I had to get pretty contorted at times when it was the ONLY grind I had, but I managed to get a pretty nice cut across the bottom of my bowls with them.
I STILL can't get a good enough cut with the Elsworth grind gouges on the bottom. It may just be technique, it might be a stubbornness, I don't know. So far, I still rely on those tools and if you took all but one, I would probably keep the old grind (so long as I can keep my detail gouge, roughing gouges and all of my scrapers.

[Dennis Ford]

Curt, you have opened a can of worms with this thread! I have yet to meet two people who can agree completely on the many variables involved here. We should get a lot of opinions. The variables that I can think of at the moment:
* Cutting angle
* Hardness of the steel
* Wet or dry wood
* Grinding grit / honing?
* Shape of the gouge ie: traditional vs Irish grind vs other
Combine these with different turners using different techniques and different priorities; ease of cut vs edge life vs ease of sharpening.

My favorite bowl gouge is HSS, the cutting angle is ~ 50 deg. The shape is somewhere between a traditional and an Irish grind. It is easy to sharpen on the aluminum oxide wheel that came with my Woodcraft grinder. I have one with a traditional grind @ ~ 70 deg for the bottom of bowls. For roughing green wood, I like a cutting angle of ~ 40 deg.

I use a silicon carbide wheel (green) to sharpen powder metal tools.

[Matt Hutchinson]

Well, I can't say that I have a terribly specific grind I prefer, but for bowl gouges I use a 3/8" 'v' flut bowl gouge that has a VERY swept back fingernail grind. I can get great roughing and finish cut off of it.

When I buy a new tool, I absolutely have a reason for getting it other than "I need a new one". This usually means I have a very specific grind I plan on putting on it. So the grind I want to use will usually determine which tool I purchase.

Hutch

P.S. As for wheels, don't have any deep knowledge about that. But I use a 120grit Norton SG wheel.

[Dale Bright]

I have several bowl gouges in different sizes and grinds. The ones I use most are 1/2 and 3/8 inch that have a 40 degree grind that I learned from Stuart Batty. There are very versatile for both spindles and bowls. They have to be sharpened by hand and that took a litlle practise. They are similar to the Johannes Michelsen grind, in that a catch is less likely.

Dale

[Bob Bergstrom]

I use this grind to turn pretty thin bowls. The narrow nose (about 3/16") allows me to get into small areas. It also allows me to apply a minimal about of pressure to get a resulting cut. The cuts off the tip are as narrow as a bristle on a large paint brush. The low wings aren't great for shear scraping, but keeps the center of gravity of the tool very low. This stability is a plus when turning as thin as the bowl below. It measures a little over a thirty second of an inch thick.
http://i306.photobucket.com/albums/nn274/bbergst/IMG_2584.jpg
http://i306.photobucket.com/albums/nn274/bbergst/IMG_2824.jpg

[Steve Schlumpf]

Curt - my go-to bowl gouge for just about everything I turn is a Doug Thompson 5/8" V and I have it mounted in a Monster Custom Handle that is loaded with BBs for ballast! Love it!

The grind I use works for me and has been developed over time. The cutting angle is 42* and the actual nose area varies from 1/8" to 3/16" max. The wings are swept back approximately 1 3/4" to 1 7/8" and if you check out the photos - you will notice that I grind the heel back to minimize the nose/contact area and then I grind that secondary bevel back also so it doesn't interfere with the transition area inside of the bowl.

151900 151899

I have no problem using this gouge for roughing out blanks or super fine finishing cuts. The only difference for finishing cuts is that I sharpen the gouge again before making the final cuts. Great tool/handle combination!

Oh, wanted to add that I use the Wolverine sharpening system with the Woodcraft slow speed grinder. I use a 150 grit wheel for touching up the edge on the gouge and a 120 grit wheel for my scrapers.

[John Keeton]

My Thompson 5/8" V bowl gouge is ground just like Steve's - and, that is not coincidental!! I have seen these pics before!;):D Works great!

[Allen Neighbors]

I have a question for you, Steve, or John: How is that 42 degree cutting angle measured?

[Bernie Weishapl]

I pretty much use the what Steve and John use with the big swept back wings. I also have two others that I have patterned after attending a demo given by Mike Mahoney. I use one conventional grind, a gouge to hog with and then a gouge that is really swept back for shear scraping. The one to hog wood (has the bevel shortened) and the conventional grind are 40* and the shear scrape is 50*.

[Steve Schlumpf]

Allen - my measurement was real scientific - I used one of these (http://www.hartvilletool.com/product/12511), it's magnetic so just placed on top of the gouge inline with the flute, lifted the gouge up until I couldn't see any light under the main bevel and checked the reading - 42*

[Cathy Schaewe]

This is a fascinating thread - now I'm going to have to go measure my grind angle. I'm used to what I've got, which is nowhere near as fancy as these double grinds, etc., but why not try something new!

[Richard Madison]

Thanks Steve. Will try that. Should be interesting.

Favorite grinds are moderately swept back, the same way that Doug sends them out, and one conventional/traditional (angles to be measured tomorrow) for shear scraping inside and out.

[David Peebles]

Here are my grinds. The first two are at about 60 degree nose angle, and the big one is about 62. They work well for me... but that is the angle that I learned on.

I have experimented quite a bit over the years, but keep coming back to these. 60 grit wheel for most of my sharpening.

Best wishes,

Dave

[Reed Gray]

Well, I haven't settled on any one grind. I did take a 3 day workshop with Allen and Stewart Batty, and that got me to start experimenting with the more standard grind, 45 degree bevel, 45 degree sweep. I like it, but find it more suited to shallower bowls, and totally unsuited for deeper bowls except for going down the sides. You need a more blunt angle for making the transition on the inside of bowls. I use less sweep back, closer to the medium one that Bernie shows.

As far as I know, I am the only turner who used CBN (cubic boric nitride, or some thing like that) grinding wheels. I don't know what the hardness is on them, but probably Z. It is an aluminum core with 3/16 of matrix bonded to it. My 80 grit wheel is maybe 4 or 5 years old, and still has 1/8 inch of material on it. They are already balanced when you get them. Down side is cost is about $300 per wheel. They are made to order, in whatever grits you want. I had a 320 grit wheel, but it was softer and wore out quicker. I now have a 150 grit wheel. Much finer surface left than what you get from standard grinding wheels.

I haven't used a grinding jig all year, and never will again. A platform is much more efficient.

robo hippy

[Wayne Spence]

Doug-Who is Johannes Michelsen? I am always reluctant to ask as the person sometimes turns out to be the god of sharpening or some such figurehead.

[Doug Thompson]

Johannes can be found here woodhat.com He's the guy who taught me how to turn the "right way"... anyhow it works for me... the guy is impressive to watch.