Bowl gouge grinds

[Jack Tyree]

I recently got a DT 1/2" U shaped bowl gouge and use it with the standard grind it came with. I use the Wolverine system and have no trouble duplicating that grind. I also have a 3/8 V shaped gouge and use it with the standard grind also, but I guess because it is a V shape it seems to cut quite a lot nicer. I meant to get the 1/2" in the V shape too, but I messed up, I guess. I want to experiment with more of a side grind now and want to get another 1/2" to keep in that grind. Should I get a U shaped or a V shape for that grind? (And why do they cut so much differently?)

[Steve Schlumpf]

Jack - everyone will have a different opinion on this - but - seeing as how you already have a 'U' shape - I would go with the 'V' shape and then you can actually compare both and see what works best for you.

I have the 5/8" V from Doug and it is my go-to gouge for everything! I can rough out bowls and hollow forms or make extremely fine cuts... but it does come with practice!

I have a swept back grind on my gouges and I use the wings more for sheer cuts than anything else but can take off some seriously wide curls when roughing out a blank!

[Jack Tyree]

I knew you used a swept back grind on your gouges and hoped you would reply. I decided to try and learn to grind and use them after watching a video of Tim Yoder taking wonderful shear shavings on the outside of something(?)

[Steve Schlumpf]

Jack - I do have a fairly radical swept back grind but it is something I worked in to over time and something that works for me and my style of turning.

If you are just starting out with a swept back grind - be aware of those sharp wings when you go to use it - or YOU WILL SLICE your hand! I wear a glove on my left hand and it has many slices from when I hold the gouge against the tool rest! Just something to be aware of!

[Bernie Weishapl]

I also have a 5/8" and 1/2" Thompson gouges with a really swept back grind. I like the long swept back wings for doing the vertical shear scrape like Bill Grumbine uses. It really makes a smooth surface especially where there is a lot of tear out.

[William Payer]

I have four Thompson bowl gouges (3 "v" and one "U") along with a couple of Sorby bowl gouges/ I sharen them all with the same jig setting on my Tormek ( protrusion of 75 mm and on #6 position) Although I like the Thompson gouges I find the Sorby's to cut much cleaner. I think the Sorby's are more of a "U" shape. I just wondered if anyone else has noticed some designs cutting better than others with the same sharpening settings?

[Thom Sturgill]

I have a DT 5/8" U in a conventional grind with the heel rounded that I use for the transition area on bowls. I also have 2 other 5/8 - a crown and a Ellsworth sig. I also have DT 1/2" and 3/8" Jimmy Clewes V (sharper than the normal V).

On the U more of the 'nose' gets involved when cutting with the point because it is so much wider. The Ellsworth seems to get sharper than the others. Its flute is parabolic which effects the shape of the wings. The Clewes flute is a sharp V with straight sides giving a good straight wing for shear cutting.

Differences in grinds, steel, and flute design all make them hard to compare, but also make each perform different tasks better than another. I just have to remember which is which.... then a little sometimers kicks in

[Harlan Coverdale]

Should I get a U shaped or a V shape for that grind? (And why do they cut so much differently?)

I find it's handy to have both U and V shapes. I tend to use the V shape on the outside of bowls, since I like the shearing cut I can get with the relatively long wings. I like the U shape inside a bowl, since I can get a shearing cut with the more rounded tip of the gouge. I think if you have both in the same size(s), you'll find certain tasks that one excels at over the others.

[Jake Helmboldt]

How does the Thompson V-flute compare to the Sorby? I've seen some posts say the Sorby is parabolic while others say it is more akin to a U.

[Neil Strong]

There was a time when all we could get were U fluted gouges, so still have a few of them in the tool rack but only reach for them very occasionally now that we have so many V flute (actually Catenary or Hyperbolic cosine or Parabolic) gouges available.

Perhaps the one U fluted gouge I still reach for quite a bit is the big P&N roughing gouge, but other than that I wouldn't bother buying another U'ee.

.....

[Josh Bowman]

Jack - I do have a fairly radical swept back grind but it is something I worked in to over time and something that works for me and my style of turning.

If you are just starting out with a swept back grind - be aware of those sharp wings when you go to use it - or YOU WILL SLICE your hand! I wear a glove on my left hand and it has many slices from when I hold the gouge against the tool rest! Just something to be aware of!

Steve,
Could you post a picture of your grind? My mentor has me using one that has long wings. I duplicated it on my Tormek and they call it an Ellsworth grind.
Thanks

[Dennis Ford]

I agree with Harlan, both shapes have their uses. If I had to choose just one it would be the "V" shape but a "U" shape with a conventional grind at 60 - 70 deg works great for the bottom area of deeper bowls.

[David Woodruff]

I truly love the radically long swept back grind. With practice, really delicate cuts can be made. I have GLASERS(gloat, gloat 0 .25 up to.75 with grinds of both varieties. The V-15 is awesome.

[Richard Madison]

The Sorby "V" is shallower than the DT. I used to think is was a "U". The BB "V"'s that I have are much sharper/deeper than the DT, and harder for me to control. I use the nominal swept back grind that Doug supplies, except on the Sorby which has a straight "traditional" grind (good for shear scraping). As mentioned, wings of the DT 5/8" "V" are good for shear cuts, similar (I think) to planing cuts with skew.

[Doug Thompson]

The most common bowl gouge is the V shape, if you look down the flute at all the different brands on the market you can see that most are close to each other. This basic shape does most everything well because the small radius is easy to control. The U shape because it has the large radius will shear the wood better on a finish cut but roughing the larger nose radius IMO is harder to control. When you think about a U shape flute think push cut, Stu Batty, dry wood and finish cuts.

When you sharpen a bowl gouge remember you follow the flute shape, look down the flute then look straight down at the grind, they should look about the same.