Ellsworth Grind v Irish Grind

[Desert Pete]

I have an Irish grind bowl gouge that I use occasionally. It is pretty aggressive but, I suppose, with enough practice it came be tamed.

Rockler has an Ellsworth grind gouge on sale which looks to me to be a somewhat less aggressive Irish grind. So, the question is, "What is the practical difference?".

 

[waltben]

Nothing much. David insists on students using his grind for classes, and I believe it's a good idea as it removes a big variable when you've multiple students. The gouges with his name are quite good, about the same hardness as 2030 and I believe a bit harder than M4. I prefer a similar profile that's less angled (aggressive?), but not that much so. The term is also pretty much interchangeable with fingernail grind.

The only real difference is that David's is a specific angle, while the other terms refer to a generic shape.

 

[MichaelMouse]

The jig-made grinds have a straight line edge when you look at them from the side. The original "Irish" grind from waaaay back when the cylindrical gouges were new has some curve to it, which makes it much more friendly when moving the handle up or down to track into a bowl shape.

Other folks http://www.woodcentral.com/newforum/grinds.shtml

My version of the Irish is pictured below. It's a friendly poke and roll gouge for working in, http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=HollowTwo001.flv but I rarely use it for fairing the curve because it gives a short sweet spot in comparison to the forged gouge.

 

[Ron Sardo]

I think the difference is about $25

 

[Steve Worcester]

At one time I talked to David about this and his take is far less than you might think. Any gouge can be reshaped with a fingernail grind, but the flute shape is mighty important as well. If you can, look straight down the "barrel". One may be a "U" shape and another a "V". Thickness at the bottom of the flute also is an important factor in the usefulness and rigidity. I got some name brand powdered metal gouges and there were big discrepancies in thier own parts. Over time though you will start to find something that suits the way you work. It all starts out as an experiment.

 

[waltben]

Here's a reply from a member of the Irish Woodturner's Guild:

It was Liam O'Neill who designed the Irish Grind and it has the swept back sides along with a short grind at the tip of the bevel just at the heel, for getting to the bottom of the bowl.
I think Ellsworth copied Liam's idea but left out the short bevel.

 

[hockenbery]

Walt is on target.

Liam Oneil invented the side grind.

David shortened the wing and rounded the nose a bit more gently.

I had five day class with Liam in 1994
and a 5 day class with David in 1995 two great experiences.

I prefer David's grind. It has a beefier shoulder that supports shear cutting.

I often grind the heel from the Ellsworth grind to shorten bevel allowing the bevel to ride through a tighter curve or deeper bowl.

happy turning
Al

 

[Steve Worcester]

This is from an interview I did with David a few years back http://www.ellsworthstudios.com/interviews/interviewDavidEllsworth.pdf

Steve: What about the "Irish grind". Which came first, you or Liam O'Niell? What have you done to this seemingly radical departure from the standard bowl gouge design?

David: I was first exposed to the ‘side grind’ gouge through Liam O’Neill in 1982.
He, Michael O’Donnell, Richard Raffan and Ray Key had all been working with
the concept in the UK, and each had their own variations of the design. What I did was to further modify the tip shape by broadening the bevel and arching the edge until I got the right proportion between edge sharpness to bevel durability.
This is particularly important because I use the edge of the gouge at an elevated angle of 45 degrees across the wood to ‘shear’ the surface for the final cut on the outside of a form. None of the other turners did this because they were trained in the traditional manner of rubbing the bevel.
The shearing cut doesn’t use the bevel against the wood, but it does use the mass of the bevel beneath the edge to support the cut; that is, to keep it from vibrating against the wood. Equally important, my design allows the gouge to be used horizontally instead of at an elevated angle on three of it’s four primary cuts.
This means that the force of the cut is now generated directly into the tool rest instead of into the turner, with the result that the cut is more efficient and the turner is less fatigued. In fact, the tool is so specific that if you put the same long edge on a gouge with a smaller diameter shaft, you loose the mass that’s needed to support the edge and, therefore, the efficiency of the tool to do a proper job.
What’s most important about this gouge design is that it was developed out of need and by people ‘in the field’, rather than on a drawing board. While its design is unique compared to traditional bowl gouges, its efficiencies are based on sound design principles.

 

[MichaelMouse]

Probably worthwhile to note that the practice of rounding out the squared upper edges of the "long and strong" gouge which was used until they started machining flutes into cylinders was of long standing. Nothing new there.

It was also the practice to trail the upper limb of the gouge to get a shear cut while taking full advantage of bevel support. That secondary grind on the heel of the bevel was used to overcome one of the shortcomings of the flute-in-cylinder grind, that of not being able to get a consistent tool thickness is not necessary if you do your final shaving with a forged pattern gouge.