What shapes do you think are most appropriate or easily achieved on V, U and "elliptical" fluted bowl gouges? Why?
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grinding different flute profiles
- Thread starter Kevin Jenness
- Start date
It's easier to say what grinds can't be put on which flute shapes. I haven't tried very many different grinds, as I'm pretty happy with the 2 I use. That said, I was unable to get an Ellsworth grind on a V flute--it needs a parabolic/elliptical flute. I can get a mildly swept back/not truly an Ellsworth grind on Doug Thompson's mostly V flutes. The more open, tending towards a U flute seems to be best for the Bottom of the Bowl gouge.
I use a swept back or fingernail going on all of my gouges.
Stuart Batty is the only one that I know who uses the term 'elliptical' flute, I use the more commonly used term 'parabolic' to describe that flute profile in my following comments.
The U flute on a larger gouge with a more straight across grind is good for removing bulk material from the outside of bowls and also for facing off blanks. But, as @Dean Center has posted, the U flute doesn't take a swept back wing grind very well, so I moved over to V and Parabolic flutes that do take a more swept back grind when those became available. David Ellsworth explains the issue with trying to grind a swept back grind on a U fluted gouge in this article...
The last U fluted BG that I had was the D-Way 3/4", which I got for bottom inside of bowl work in larger bowls and platters, but I didn't like it at all as it didn't have enough meat left below the bottom of the flute for that use, so I also gave that one away and now don't have any U flutes.
That leaves me now with just V and Parabolic flutes in my BG rack. All with swept back wing grinds and with three different nose bevel angle grinds; 65, 55 & 42°. It would be more sensible to have just two nose bevel angle grinds, like 60 and 42°, but it would be hard to let the 65° go as it was my workhorse for decades and it doubles as my inside bottom of bowl gouge nowadays. The Henry Taylor parabolic flute ground with a 65° nose bevel is my preferred gouge for that...
I find that Parabolic is the most versatile across all three of my nose bevel angle grinds, but the Parabolic flute is the best for taking my 42° grind.
The V flutes work equally well for me across my 55 and 65° nose bevel angles, with some variation between the makers, but not enough to be significant. I added the V flutes initially because I wanted some more durable 10V and M42 gouges and the V flute profile was the only style that came with those steels at the time. That has since changed and both of those gouge steels can be purchased now with a Parabolic flute.
I have never had any issues with shavings clogging in either the V or Parabolic flutes and the majority of my wood is pre-turned when fresh green.
Now that 10V, or 15V, and M42 gouges are available with parabolic flutes I'm unlikely to buy any more V flutes, but I'm very happy to keep using the ones that I have.
Stuart Batty says that an 'elliptical' flute (his word, which I interpret as parabolic) is best for his 40/40 grind, which is what I also found with my 42° grind. I would say that applies to any swept back grind with a 45° or less nose bevel angle.
The U flute on a larger gouge with a more straight across grind is good for removing bulk material from the outside of bowls and also for facing off blanks. But, as @Dean Center has posted, the U flute doesn't take a swept back wing grind very well, so I moved over to V and Parabolic flutes that do take a more swept back grind when those became available. David Ellsworth explains the issue with trying to grind a swept back grind on a U fluted gouge in this article...
The last U fluted BG that I had was the D-Way 3/4", which I got for bottom inside of bowl work in larger bowls and platters, but I didn't like it at all as it didn't have enough meat left below the bottom of the flute for that use, so I also gave that one away and now don't have any U flutes.
That leaves me now with just V and Parabolic flutes in my BG rack. All with swept back wing grinds and with three different nose bevel angle grinds; 65, 55 & 42°. It would be more sensible to have just two nose bevel angle grinds, like 60 and 42°, but it would be hard to let the 65° go as it was my workhorse for decades and it doubles as my inside bottom of bowl gouge nowadays. The Henry Taylor parabolic flute ground with a 65° nose bevel is my preferred gouge for that...
I find that Parabolic is the most versatile across all three of my nose bevel angle grinds, but the Parabolic flute is the best for taking my 42° grind.
The V flutes work equally well for me across my 55 and 65° nose bevel angles, with some variation between the makers, but not enough to be significant. I added the V flutes initially because I wanted some more durable 10V and M42 gouges and the V flute profile was the only style that came with those steels at the time. That has since changed and both of those gouge steels can be purchased now with a Parabolic flute.
I have never had any issues with shavings clogging in either the V or Parabolic flutes and the majority of my wood is pre-turned when fresh green.
Now that 10V, or 15V, and M42 gouges are available with parabolic flutes I'm unlikely to buy any more V flutes, but I'm very happy to keep using the ones that I have.
Stuart Batty says that an 'elliptical' flute (his word, which I interpret as parabolic) is best for his 40/40 grind, which is what I also found with my 42° grind. I would say that applies to any swept back grind with a 45° or less nose bevel angle.
In the Thompson Tool booth often I would be asked which is better U or V. I answered saying that I prefer the V. The U for me feels like it self feeds and with the V I have more control. Control is king! To this day even though I have U gouges I do not use them. For me I have never found any advantage of parabolic tools over the V tools I use (I've tried them), after 20 years of using Thompson V gouges anything else feels foreign.
I did not like the deep V flute on the old Glaser gouges. They were prone to clogging up with chips. The more open V flutes like the Thompson or D Way work fine, and also work fine for the 40/40 grind and the swept back grinds. I do not use a swept back grind at all any more. The U flutes or half round flutes do not work well for swept back grinds, but both work fine for BOB (bottom of bowl) specialty gouges. My favorite BOB gouge is a spindle detail gouge with a 70 degree bevel and a ) nose profile. I do use the 40/40 and a BOB tool for all of my bowls. I use dedicated scrapers with burnished burrs for shear scraping my bowls as my finish cut. Nothing wrong with the swept back grinds, but to me, they are a "one tool does it all" type which means that they do a lot of things well, but the specialized tools work better.
robo hippy
robo hippy
This thread got me thinking about the different types of flutes. I went to Thompson to look at his offerings from a search on this topic. One response i saw mentioned the fluteless gouge with a link to a @robo hippy video. To bad Thompson doesn't have a picture of said tool.
Gregory
Gregory
I have two 5/8" bowl gouges, one a Crown "parabolic" and the other a Thompson V, both ground to the Ellsworth formula. For a while I was grinding the Thompson gouge by hand (no jig) to a 40-40 profile. Other than having to take care at the transition between nose and wings to avoid a "birds beak" I don't see any great difficulty in grinding either profile on a V gouge, and the V and parabolic gouges seem to work about as well for me with the Ellsworth grind. I haven't used a U gouge, but it looks to me as if you should be able to grind one as well as a V to the Ellsworth profile, even if Ellsworth didn't manage it.
What I was really trying to get at with my initial post is this; aside from the ease of shaping a particular profile on a particular flute shape, is there a profile that is more appropriate to a given flute shape, that works better? Is a parabolic gouge better suited to an Ellsworth grind than a V because it typically has a wider nose, or because it has a more gradual transition between nose and wing, or because the wings are curved rather than straight? Is a U gouge unsuited to an Ellsworth or a 40-40 grind because the flutes are parallel or because it is harder to grind that way? (Asking for a friend).
What I was really trying to get at with my initial post is this; aside from the ease of shaping a particular profile on a particular flute shape, is there a profile that is more appropriate to a given flute shape, that works better? Is a parabolic gouge better suited to an Ellsworth grind than a V because it typically has a wider nose, or because it has a more gradual transition between nose and wing, or because the wings are curved rather than straight? Is a U gouge unsuited to an Ellsworth or a 40-40 grind because the flutes are parallel or because it is harder to grind that way? (Asking for a friend).
Several make and sell variations of a fluteless gouge, for example the Skewchigouge. Some make them in their shop, I've made several myself. Can be ground from a round bar steel flat on top and round on the bottom. I sharpened one for a friend recently. Can be better for tighter coves than a skew. However, I prefer the skew for things like planing, peeling, facing, and v-cuts.
JKJ
I have a Thompson “u”. Haven’t found a grind for it I like. I bought it for use as a smaller Ellsworth grind, but can’t get the wings swept back and still have a continuous smooth cutting edge. Now I know why. Hoping to hear more here about what a “u” gouge does best, and with what grind.
I guess without seeing a picture in didn't put fluteless gouge and skewchigouge together. Thanks for helping me figure out what it is.
Gregory
I picked up a Thompson fluteless gouge after watching Robo's video. At first I had trouble getting it to work for me but I've been using it more lately as a problem solver in bowl bottoms and often as a scraper.
The bottom of this page has some photos of the grind for the round-bar type. Keep in mind that different turners may have different terminology for the similar tools and the similar terminology for different tools. Good fun.
Note: I am not necessarily endorsing this article, it's just one I found. Note especially that he says "I have been ... turning for just a couple of weeks."
It also describe methods of sharping, some seem unnecessary. I just grind and sharpen things like this by hand.
Note the similarity of side view of the top grind to my Wicked Point Tool, designed independently, maybe 10 years ago. Tells me a lot of turners have probably ground tools with at least some similar features. For every "original" idea, someone else probably already came up with it.
JKJ
For reference, here are the flute profiles on the Glaser BGs, early version on the left and a later version on the right...
Doug Thompson's V picks up on the style of Glaser's later design and is just a bit more open...
I have and regularly use both V and Parabolic BGs and for the most part I don't find a lot of difference between them with the grinds that they will take, but the more open the V the more versatile they seem to be. For example, the wider V flute on the Lyle Jamieson V BG is slightly more forgiving of various bevel grind angles. That BG to Lyle's design is another case of a V flute being (to my eye) incorrectly described as parabolic. Again a very nice BG, but just misnamed.
The true parabolics that I have (Henry Taylor, Crown, Woodcut & Vicmarc) do take my 42° grind a bit better than the Vs, but the parabolics seem to get on well with all of my bevel grind angles.
Mike
I will leave those who are still using the U gouges to answer your question about what they do best. I stopped using them myself a long time ago.
Way back when I only had U fluted BGs I also never had any success in putting a swept back wing grind on any of them and is the reason I eventually moved them all along. My understanding of the the geometry is that the U flute and a deep swept back grind are incompatible. But, I may be wrong about that, so I would love to see some photos from anyone who has managed to put a swept back wing grind on a U fluted gouge.
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Most professionals (including myself) will recommend and use parabolic flutes on bowl gouges. Someone asked me in a demo why they even make the other shapes still and I honestly don’t know. Parabolic would be my choice every day of the week. Far easier I grind into a versatile and useable shape.
Richard
Richard
You can't put wings on the Thompson U gouge, the geometry just doesn't allow it. The Thompson V is more open than the Glasers because if you have ever used the Glasers you know that the tip clogs. Before starting out Glasers were what Doug used so he fixed that.
I made this video recently about an old Sorby profile which is horrible to sharpen with a fingernail profile:
View: https://www.instagram.com/reel/DA5xQRrMVJP/?igsh=aHliaWtvczU0MXNl
I think almost any tool can be made to have a fingernail grind, some are just much more difficult than others
Richard
View: https://www.instagram.com/reel/DA5xQRrMVJP/?igsh=aHliaWtvczU0MXNl
I think almost any tool can be made to have a fingernail grind, some are just much more difficult than others
Richard
Thanks, Richard. How does that gouge perform once you do get a fingernail grind on it?
It's interesting that several commenters to your post say they have been sharpening and using that profile for a long time. I guess you can get used to anything.
There seems to be a consensus that a continuously curved ("parabolic") flute profile is easier to grind to a swept-back or fingernail shape than a V, and much more so than a U. It seems that the closer to parallel the upper flute walls are the harder the task becomes. The sudden transition from the flute bottom to straight walls is an issue as well, one that I have adapted to with my Thompson V. The flute radius seems to play a part as well, with larger radii easier to blend to the straight sides.
A club member brought in a V gouge with a very tight bottom curve and a hell of a birds beak at the transition. I was able to grind a smoooth shape on it but only with difficulty. The very open V on The Thompson/Jamieson gouge seems to give little problem, to the extent that it is marketed as a parabolic flute.
It's interesting that several commenters to your post say they have been sharpening and using that profile for a long time. I guess you can get used to anything.
There seems to be a consensus that a continuously curved ("parabolic") flute profile is easier to grind to a swept-back or fingernail shape than a V, and much more so than a U. It seems that the closer to parallel the upper flute walls are the harder the task becomes. The sudden transition from the flute bottom to straight walls is an issue as well, one that I have adapted to with my Thompson V. The flute radius seems to play a part as well, with larger radii easier to blend to the straight sides.
A club member brought in a V gouge with a very tight bottom curve and a hell of a birds beak at the transition. I was able to grind a smoooth shape on it but only with difficulty. The very open V on The Thompson/Jamieson gouge seems to give little problem, to the extent that it is marketed as a parabolic flute.
Bottom feeder.
Then there is the Sorby Spindle Master. It was their attempt to replicate a tool that Allan Batty used. Allan commented "They got it all wrong." Allan's tool, and one that Cindy Drozda and Stuart use and I think they call the "vortex" tool is much closer. It is half round bar stock on the end, like the Thompson Fluteless gouge, but it is sharpened more like a spindle detail gouge, so the edges are swept back. I have one of Doug's fluteless gouges that I sharpened that way, and it is great for getting down deep into a spindle cut for clean up. I guess the wings can be used to slice and clean up coves as well. The problem with the Spindle Master tool is that they made them out of very thin stock rather than half round.
robo hippy
robo hippy
I have two of Doug's fluteless gouges and find them indispensable. They have a 'scraper' style grind on the nose, a flat top side, with a round bottom. I don't use them on every piece but find they're great at removing fine tool marks and the like. The round bottom allows you to 'roll' the nose to just the right angle. Let me know if you'd like photos of the tool and I can send you a couple.
Thanks for the offer, I have a very good mental image now. Your description is pretty Illuminating as well.
Gregory
I have a 3/8" U-flute Thompson gouge that I bought before I really knew better. I saw @hockenbery recommend using such a gouge with a Michelsen grind for the top 1" inside a bowl, so I tried it, and it works great. (Jimmy Clewes also recommends finishing the top inside of a bowl with a small gouge before hollowing to the bottom, though he uses his standard grind.) I still find an Ellsworth grind more versatile than the Michelsen grind for my larger gouges, but that little 3/8 gouge is perfect for light finish cuts close to the rest, with the flute either all the way open or close to it.
I am, however, very interested to see what grinds others are using on their U fluted gouges, other than the traditional straight across grind. Some photos would be very much appreciated.
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I learned that from Jimmy too. I like the Michelson grind for the small gouge more than traditional
Like the Ellsworth for most other things.
I could be wrong but I thought this was a Thompson U gouge.
Rusty
Can't tell from that photo. Can we see an end-on photo of the flute profile?
Here is the grind that Carter & Son put on their 5/8" U-fluted 'Bottom feeder" BG with a 60° nose bevel angle...
https://cdn10.bigcommerce.com/s-pa1...uge_2_WEB__64809.1441249235.1280.1280.jpg?c=2
I have used a slightly similar grind on a large U-fluted gouge that I used for facing off blanks, but with a more acute nose bevel angle...
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I can see how the Michelson fixture solves the problem I’m having getting a swept back grind on my 3/8” U gouge. I don’t have the words to explain it, but I can see it.
Would it also help make a V gouge work more like a parabolic? Starting out, I just bought “bowl gouges”, not understanding the difference between u, v, and parabolic. So now I have 2 v’s, a “u”, and a parabolic, each a different size. I find the parabolic easiest to use. I’m starting to wonder if it’s because my sharpening system is best for parabolic?
I also like that it can grind all the way down to the end of the flute. I have a detail gouge that I’m already having to grind a flat on top by to use with my Tormek jig. I use a regular 8” slow speed grinder with the Tormek jigs.
Unfortunately, I don’t have a Oneway base, so getting set up to do the Michelson grind would require buying a Oneway base as well as the Michelson kit. I’ll need to find a way to try it out before spending that much.
I also noticed in the linked videos that based on the amount of sparks, he’s grinding a lot more steel away at each sharpening than I do with my Tormek jig on 8” slow speed grinder. I wonder if there is a reason for that?
Would it also help make a V gouge work more like a parabolic? Starting out, I just bought “bowl gouges”, not understanding the difference between u, v, and parabolic. So now I have 2 v’s, a “u”, and a parabolic, each a different size. I find the parabolic easiest to use. I’m starting to wonder if it’s because my sharpening system is best for parabolic?
I also like that it can grind all the way down to the end of the flute. I have a detail gouge that I’m already having to grind a flat on top by to use with my Tormek jig. I use a regular 8” slow speed grinder with the Tormek jigs.
Unfortunately, I don’t have a Oneway base, so getting set up to do the Michelson grind would require buying a Oneway base as well as the Michelson kit. I’ll need to find a way to try it out before spending that much.
I also noticed in the linked videos that based on the amount of sparks, he’s grinding a lot more steel away at each sharpening than I do with my Tormek jig on 8” slow speed grinder. I wonder if there is a reason for that?
If it is the same video, in the first section he is grinding with a #40 wheel to quickly form the bevel and wings. Finer CBN, or whatever, wheels are all that is needed after that to regularly refresh the edge.
The only U gouge I use, and that use is very rare, is a 3/8" U ground about 80° off 90. Its use is only for really difficult wood at the transition area between the side and bottom of the bowl when no other tool will clean up the tear out in that transition area.