22mm supagouge

[Adam Petersen]

Hi,

I just got a 22mm P&N Supagouge for roughing blanks. Any suggestions on bevel angles and grinds for that purpose. I've never had a large rougher, so I thought I'd ask before I put steel to CBN.

Thanks,

Adam

[Reed Gray]

Surprised there are no answers here, well not yet... I am biased because I use scrapers for all of my bowl roughing. I do use gouges as well. Most of the time it seems that that style of gouge is ground in the swept back/Irish/Ellsworth design/profile. This is generally a 60 degree bevel and the wings are ground back an inch or so on the sides. The 60 degree bevel is kind of an all purpose angle which means that if you grind off the heel of the bevel, you can go through the transition and across the bottom of most bowls without having to switch to a BOB (bottom of bowl) specialty tool. The long wings are good for shear scraping, and for heavy roughing cuts if you drop the handle to a more shear angle rather than holding the tool more level. Of course, you have to have the horse power to be able to take that big of a cut. I don't use swept back gouges at all. I do all of my roughing with scrapers, and all of my shear cuts with scrapers as well, so they have no other practical use for me. One can never have too many tools.... I prefer a 45/45 grind for most of my finish cuts on the outside of a bowl, and on the inside walls. For some reason, a 60 degree bevel just doesn't feel right for any heavy stock removal, and the 45/45 or Stuart Batty's version the 40/40 takes less effort for the roughing cuts. So, I do keep a number of 45/45 gouges, and a number of BOB tools with different flute shapes, but all have a ) shaped nose so I can roll them over and get a very high shear angle for cleaner cuts.

robo hippy

[Adam Petersen]

Thank you for the in-depth reply Reed. Definitely give me something to ponder. This is a big darn gouge, so I was debating what was best for roughing but also maybe as a BOB since it could handle the extension off the tool rest. I'll probably experiment with some of those different angles you listed.

[Dennis Ford]

A bottoming gouge works best for me with a large angle (~70 deg). A roughing gouge works best for me with a more aggressive angle (~45 deg).

[Robert Willing]

https://www.youtube.com/watch?v=3liDhY_zxSc I would suggest reviewing all of Lyle Jamieson youtubes on sharpening.

[Don Frank]

Reed,
That's good info. Do you grind your 45/45 freehand or use a wolverine jig? An off topic question, what angle do you prefer to put on the scrapers you use for roughing cuts? I've been doing 70 degrees but have not experimented with other angles. tks

[Reed Gray]

Don,
I haven't used a gouge jig in so long, I don't know if I could even figure it out now. Platform sharpening only. According to Stuart Batty, you can not get the 'proper' grind on the 40/40, or the 45/45 that I use if you use the jigs. Not sure exactly what the difference is, but guessing, most jigs do not allow you to roll over far enough so jig grinding leaves a more acute wing angle, and hand rolling gives a more blunt angle. I do have a video clip up on platform sharpening.

For scrapers, I have them all at 70 degrees. As near as I can tell, that is what they all were when I got my first ones many years ago, and I have never experimented beyond that. There are a number of turners, and I think most of them are from England and Ireland, who prefer a more acute angle. I do think the 70 degree bevel forms and holds a more heavy duty burr. Grinder burr (80 or 180 grit CBN) for roughing, and burnished burr for shear scraping.

robo hippy

[Don Frank]

Reed,
I'll look for that video. I don't think I've seen that one before. I have your Robo rest and love that thing. Tks for the info.
Don

[Adam Petersen]

Went with the 45/45. Looks good and seems to cut okay just playing around with it. I'll give it the paces early next week. I have a project for a friend that will allow me to use this for roughing out the shape. Thanks for the advice.