Revised Bowl Gouge Opinion & Apology

[Richard Madison]

In the unlikely event that anyone followed my opinion to buy a U gouge (versus the overwhelming majority who favor a V gouge), and is dissatisfied with it, I apologize. Having finally got around to cleaning up the grind on my new Thompson 5/8" U (same grind it came with but finer stone) and using it a bit, I found that it is not as "comfortable" as expected. Comparing grinds with my trusty old Sorby with straight conical grind, the nose angle is a bit different, maybe 60 vs 50 on the Sorby, which should not make that much difference. But staring at the business ends side by side was a revelation. The Sorby is actually a moderate V, not a U as I always thought. The error in thinking happened some time ago when I compared the Sorby to some Ben's Best gouges that I do not like, and that are a rather sharp V shape (I think). I erroneously concluded that since the BB tools were obviously V's, the Sorby was a U, when in fact it is not.

So again, knowing that many of us must be economically careful and selective in our tool purchases, if my posted opinion has led you astray, I sincerely apologize.

[Allen Schmid]

Well Richard,
From the overwhelming responses you should come to realize that all is not lost but it is nice to see you explain your situation and outcome. I especially like your last sentence concerning the idea to be "economically careful and selective", it rings true with me and many others who are making purchases that may not always be the best timing (financially). That is a good thing to see and I am sure all who read it appreciate your candor.
I have come to really like the v-gouge and find that it is versatile and efficient.
Thanks again for sharing,
Allen

[Steve Schlumpf]

Richard, now that you have your grind cleaned up, I am curious as to how you like the gouge on the inside of a bowl? According to Doug's site, that is where the 'U' gouge is suppose to work best!

[Ryan Baker]

I have a 5/8" U Thompson, but I can't really comapre it to the 5/8" V since I have a traditional grind on it. It works great for the bottoms of bowls. Very smooth and clean cuts. (And I like the 5/8" for this application for stability hanging farther over the rest.) Maybe one of these days (when I have some spare cash), I will try one of the U gouges with an Irish grind.

I tended to think of my Sorbys as U shaped too ... since they were certainly closer to a U than various other V gouges I have. Certainly there are different varieties of V and U in the market -- one brand's definition does not necessarily match another. Doug's U shape is quite wide in the flute, IMO, while the V is certainly a lot different (and improved IMO) than other V designs.

[Richard Madison]

Allen, thanks for your reply. I appreciate it.

Steve, I have not turned a bowl for a while, but will keep you posted. Being self-taught (inadequate teacher) and somewhat isolated, my techniques are probably a bit odd. I tend to turn the inside bottom of a bowl with the Sorby and sides with home made boring bar w/ HSS tool bit, then turn up speed and clean up with home made tool with Hunter cutter. Can do fairly decent segmented stuff but am really just an average turner. Maybe a little below average actually. Have an idea for a new ribbon piece but can not get motivated to start on it, so maybe a good time to do a couple bowls and practice with the Thompson. Will probably learn something.

[Doug Thompson]

The flute shape dictates how the tool will be ground and you grind a tool following the flute shape. A V shape flute will have a small nose radius and straight wings and the U shape will have a large nose radius and narrow wings. If you don't follow the flute shape when grinding by creating another shape grind example a v shape grind on a U shape flute the cutting angles are lost not on the nose angle but around to the wings. This is tough to put into words...

I don't know how to put this in words either but if you look at the shape of the flute then look straight down at your grind you should see almost the same shape created on the inside of the grind... well the flute that hasn't been ground yet.

All the professionals except Stu Batty use a V shape flute... we all know Stu does wonders with this flute shape but that's him... I bet he could turn a bowl with a butter knife too.

I'll be back in a few minutes on another post.

[Doug Thompson]

The U shape flute because of the larger nose radius is good for a finish cut, when the tool is rolled the cut is shearing the wood across the large radius with no tearout. The finish cut inside a bowl or dry wood turning when you want no tearout is where this tool excells over a V shape tool. IMO - a secondary bevel like Stu Batty uses is the way to grind this tool but there are a hundred ways to grind a U shape tool.

[Richard Madison]

Doug, in your first post it sounds like you are saying that whatever the flute shape, the tool should be ground to have a uniform included angle at every point along the cutting edge. Is that correct? Think I have read that the "Ellsworth" grind has a uniform 60 degree included angle all around. Believe that is achievable with considerable variation in the extent of "swept back" or "fingernail" grind.

Meanwhile will use new gouge some more and try to become a more skilled turner.

[Doug Thompson]

Richard, the angle does change with the nose say at 60 degrees and the wings... well I can't measure right now but it's less. If you go to my site and look at the sharpening guide, this leg angle works very well on a bowl gouge at a 60 degree nose angle or within 8-10 degrees of that. My jig angle is very close to the Ellsworth and the jig setting came from an Glaser tool a long time ago.

Johannes Michelsen and Stu Batty both use a constant angle around the entire cutting edge of the tool. Johannes a 45 degree on a V shape tool and Stu a 40 degree angle on a U shape flute... interesting. Both use a very large secondary bevel so the cutting bevel is less than a 1/8 inch, both IMO are better grinds than you can do with a jig but they take time to learn. I use a grind something like Johannes and the cool thing is it won't catch.

[Gordon Seto]

The sharpening jig that can result a constant angle all around the whole edge on side grind bowl gouges has not been invented yet.
This sharpening YouTube by Mike Mahoney is the Stuart Batty method. The only difference is the nose angle at 45 instead of 40.
http://www.youtube.com/watch?v=4m8-8MNhpvY
The following is by Johannes Michelsen
http://youtube.com/watch?v=wevTPeJoOrs
If you have a chance, please watch "Two ways to make a bowl" & Jimmy Clewes turning DVD. You will notice the different approaches they turn the inside of bowls with bowl gouges only.
These pros gliding on the short primary bevel, they bring the full potential what bowl gouges can do.

[Burt Alcantara]

Gordon,
Which Jimmy Clewes DVD?

Burt

[Gordon Seto]

Burt,

He has demonstrated the technique in several of his DVDs. "Turn it On" Vol 1 has the most detail.
Jimmy uses a small gouge for the finish cut.
On the contrary, Stuart Batty uses a long and big gouge from the transition to the bottom.
There is more than one way to achieve excellence.
Unfortunately the Stuart Batty DVD is more of a show off. I have seen his live two day demos, there is no way the information can be compressed into half a DVD.

[Reed Gray]

Flute shapes vary a lot. The Glaser V is much steeper than Dougs V, and Dougs U is more of a C to me. The biggest difference in use to me is that when using the V gouge, you keep the flutes more upright when doing a finish cut, and with the U gouge, you keep the flutes at more of a 45 degree angle. I do prefer the U gouge on the inside of a bowl. Dougs V works very well also, but I don't like the steep Glaser V on the inside of a bowl, but it does work nicely on the outside of a bowl.
robo hippy

[Richard Madison]

Thanks again to all who replied. Became a more interesting and educational (to me) thread than expected.

[Richard Madison]

Per Steve's request, did some practice on a little 4" pecan dish with Thompson U (C?), Sorby "moderate" V, and BB "sharp" V. Tried to focus on tool usage this time instead of the usual vision of finished piece. For ref. I usually cut flat or slightly curved inside bottoms with pull cut from the center out, which I think is bass ackwards. Anyhow the Thompson is indeed smooth and easy to control across the bottom, until reaching the curvature up to the bowl/dish sides. Also fine for shear scraping the O.D. The Sorby is still relatively easy across the bottom and a little further up the curvature. Also ok for push cut from the rim down, but easy enough to get a catch if attention to tool presentation slips a bit. The BB is just too tricky (too pointy) for a relatively unskilled turner like me. Fine for push cut from the rim downwards, but difficult for me to maintain correct tool presentation throughout the cut. In summary, if I had it to do again, would buy the Thompson V. Certainly the U is a good tool and would be excellent if one does a lot of shallow bowls and platters. Hope this will be helpful to someone.

[Steve Schlumpf]

Richard - just as an experiment (cause I can't see how you are holding the gouge) try a push cut with the flute of the Thompson U gouge at about a 45* angle once you get the gouge started cutting. As you approach the transition between wall and bottom of bowl - rotate the flute to an even more open position - meaning greater than 45* but only for the corner area - then rotate back to original angle. I do this with all my bowl gouges and - for me - it works great!

Other thing I should mention - I move the gouge on an ever rising arc from beginning of the cut to the transition point and then back down to center. Hope that makes sense!

[Richard Madison]

Steve,
Will give it a try. Should really learn the right way to do it rather than continuing to use my trusty home made boring bar for bowl sides. And/but think I feel the motivation for a new seg. or stave piece getting stronger.

[Gordon Seto]

Richard,

The bowl in picture is challenging on technique. With almost straight side wall, tight curvature transition to bottom. It is easy to lose bevel control at the transition. In order to get bevel contact, the nose angle grind needs to be very brunt; and the swing has to be big & swift.
http://www.woodturningdesign.com/askdale/14/14.shtml
In hollowing out a side grain bowl, the cut has to be from outside in. If you cut from inside out, it would be cutting against the grain. That is not a good test for gouges.
For bowls with so tight a curve, you may want to round off the heel of the bevel to avoid bruising of the wood fiber.

[Richard Madison]

Gordon,

That's a good reference link and I actually "got" it. Thank you. Understand that one wishes to cut "downhill", i.e. from the outside in, and/but have typically had trouble maintaining bevel contact. More practice is in order, with attention to tool control.

[Steve Schlumpf]

Another point - which I realized when you mentioned bevel control - I have the bevel on all my gouges ground back so that the bevel is no more than 1/4" long. Makes a huge difference when it comes to going through curves!

[Richard Madison]

After the Thompson 5/8U languished virtually unused in the rack all these months (had no idea it has been so long), I finally wrote to Doug and asked if he would trade for a 5/8V. He agreed, and I think he had the 5/8V in the mail to me earlier in the day than I mailed the 5/8U to him. Assumed that he would surely wait until receiving the U from me. And we know that Doug also donates many tools to benefit various worthy endeavors.

Difficult to express my amazement at this level of trust, service, and consideration. If (when) I buy or recommend another tool, it will be a Thompson.

BTW, I really like the 5/8V and am worried that he hasn't got the 5/8U back yet.

Hope this is not too "over the top", but am accustomed to dealing with companies that make millions of widgets (or whatever I bought) and could not care less about a single customer. Guess that's all. Thanks for reading this.

[Bernie Weishapl]

Richard I am a little late in jumping in but I have both of Dougs gouges. The 1/2" V and the 1/2" U. I use the V to hog wood and the U to finish. I have the bevel like Steve releived to less that 1/4" and it works extremely well. It does make a hugh difference when doing tight curves. I got the 1/2" because I just don't care for the bigger 5/8". I find I have better control with the smaller gouge.

[Doug Thompson]

The postal system is wonderful and most flutes are a basic V shape, one way or the other the shape is there... I'm glad this worked out. I sent it out with in hours of your email so I didn't forget, it's been busy with months getting ready for the national symposium and half a week playing catch up after it. Now room has to be made for 2 machines to be delivered next week, maybe in 2 months there will be time to crank them up... these are cool machines too.