Sharpening Bowl Gouges

[crokett]

I have the wolverine system. I don't do many bowls, so don't use the varigrind jig much. In this video:
Sharpening Turning Tools // WOODTURNING - YouTube

He uses wood jigs to set the rest on the wolverine jig to the correct distance for a 50 degree grind on a bowl gouge and 45 degrees on a spindle gouge. I looked for patterns online and don't see any. I would like to make a jig. How is that measured? What is the 50 degrees in relation to? Is it simply 50 degrees where the arm on the tool rest is the bottom of the angle?

 

[jrista]

I have actually had the same question, where to find patterns to make these handy angle-setting jigs for my grinder. I've mostly been using the marker technique, to mark the bevel of any tool, test until I am scraping across the full surface of the bevel, and then grind that way. But I feel my tool bevels are actually changing slowly over time, and it would be nice to be able to very accurately maintain exactly the bevel angle I want/need.

Further, to be able to do that for both traditional grinds, as well as swept back/irish/elseworth grinds as well...the swept back grinds are much trickier.

 

[crokett]

Here is a commercial version.
Raptor Set Up Tools | Shop Supplies | Craft Supplies USA (woodturnerscatalog.com)

Reading the comments in the video I

I have actually had the same question, where to find patterns to make these handy angle-setting jigs for my grinder. I've mostly been using the marker technique, to mark the bevel of any tool, test until I am scraping across the full surface of the bevel, and then grind that way. But I feel my tool bevels are actually changing slowly over time, and it would be nice to be able to very accurately maintain exactly the bevel angle I want/need.

Further, to be able to do that for both traditional grinds, as well as swept back/irish/elseworth grinds as well...the swept back grinds are much trickier.

Here is a commercial version

Raptor Set Up Tools | Shop Supplies | Craft Supplies USA (woodturnerscatalog.com)

Reading the comments in the video I linked to, he made his by borrowing a friend's commercial jig and tracing the pattern

 

[jrista]

Interesting.... I wonder if those will work with the Peachtree grinding system I just installed. I was going to get the OneWay, then realized that it was nearly $150 for just the rail guides, the long rail and the platform, and the varigrind. The Peachtree came with the same core stuff, and a ton of extra useful features. It is basically teh same thing, although I'm not sure their counterpart to the varigrind jig has exactly the same dimensions...

 

[NJturner]

I use the Raptor Set-up tools with the Wolverine system on my 8" slow speed grinder. You must also use a small stop to set the distance from the tip of the gouge to the front of the wolverine clamp. You use the Raptor gauge to set the distance from the VariGrind jig to the wheel - there are a number of Raptor Gauges, each creating a different turning grind angle. You then set the tool overhang from the jig with the little stop. The combination of VariGrind distance plus the tool overhang creates the right grinding angle.

The grind angles are pretty consistent and repeatable using this setup. This sounds way more complex in my description than it is to use - it takes me 30 seconds or so to set everything up and be ready to grind.

 

[greenacres2]

I drilled a block of white oak with holes to depth of 1.75", 2", and 2.5". Slide the Varigrind over the shaft, put the shaft in the hole and tighten the jig. The Raptors are great to set the distance. I don't know if my bowl gouges are exactly 45 or 50 degrees…but they are the same grind every time so I know how they'll behave. Now if my body would behave the same way every time, I'd get better!!
Earl

 

[crokett]

I ordered thesefrom Amazon. Together they are the same price as both of the other gauges and I had points so they're free to me.
Gouge Setup Blocks by Ron Brown's Best. Quick, Easy, Repeatable settings for sharpening bowl and spindle gouges with all popular wood lathe tool sharpening systems.

 

[jrista]

So what about swept back grinds? That is the area I have the most trouble. I actually received a set of guides like you linked from Amazon, @crokett, with my Peachtree grinding jig system. But, they only really seem to set things up properly for standard grinds, not swept back. They claim to have one config for swept back, but it seems to be radically different than my existing grinds on both my Ellseworth gouge (Crown), and my Sorby Irish gouge, and it would require taking a lot of material off to use the gauges that came with the Peachtree system. I am currently manually finding the right settings by testing with a marker, which takes time.

 

[crokett]

So what about swept back grinds? That is the area I have the most trouble.

Jigs won't work in every situation. The same benefit of repeatability means it's hard to adapt them. Im just looking for some repeatability at the moment. It's sort of a catch-22 for me. I don't turn bowls much because I have problems sharpening bowl gouges. Since I don't turn bowls much I don't need to sharpen bowl gouges, so I haven't really gotten good at it. Since I can't sharpen bowl gouges I don't turn bowls much. Since I don't turn bowls much... Anyway, once I get the basics down I will try adapting.

 

[mgoetzke]

When I was learning to bowls I was fortunate to time it right and have a two day class with Stuart Batty at a local turners club. He uses a 40/40 grind and it is sharpened by hand on a platform. I had a Wolverine system with the vari-grind jig but it didn't take long to learn to grind without a jig. You may also need a "bottom-feeder" gouge for the very bottom of the bowl. There are several videos on the internet on the Batty 40/40 grind.

Stuart also has videos online that I suggest you watch. He uses a process that is easy to follow.

Good Luck!

 

[NJturner]

Truing and sharpening a gouge with the Ellsworth Grind can also be done with the Raptor Gauges, it's just a bit more challenging. The key is to always maintain the same distance between the tool and the wheel when you do the sweep across the edge. If you can pivot the gouge correctly, you come out with a nice sweep edge without making the gouge pointy. The newer VariGrind jig with the different holder works a bit better than the older VariGrind.
I also had read a pretty good article from one of the AAW clubs on doing this with a homemade jig assembly using the Ellsworth sharpening jig (which if you are creative, you can make something similar) - you might want to take a look at this one - https://mendocinowoodturnersguild.org/wp-content/uploads/TheEllsworth-SharpeningJig.pdf

 

[penicillin]

I use Tormek jigs on the Grizzly wet grinder, which I do not recommend.
-> I wish I had bought a slow speed grinder, CBN wheels, and the Wolverine jigs or a similar equivalent.

I use the Tormek TTS-100 "Turning Tool Setter" to set the gouges and skew chisel in their respective jigs. The lesson I learned is that although it is very very good, it is not perfect at setting up the gouge/chisel in the jig before grinding on the wheel.

My solution is the same as described by @jrista in post #2, above. I turn off (unplug) the grinder for safety. I take a thick Sharpie marker and mark the bevel from heel to tip in the middle. I put the jig on the bar and look at the bevel on the wheel from the side. If the bevel isn't a perfect match for the wheel, then something is wrong. Otherwise, give the wheel a short, partial turn by hand, scraping the bevel.

Look at the Sharpie mark. If the Sharpie mark is not cleaned off from heel to tip on the full bevel, then adjust the gouge/chisel in the jig to compensate. If the grinding wheel rubbed on the heel, then back the gouge/chisel in the jig by the smallest amount. If the grinding wheel rubbed on the tip, then push the gouge/chisel forward in the jig by the smallest amount. Put a fresh Sharpie mark on the full bevel and test again.

 

[Jarod888]

As far as the swept back or Ellsworth grind,the tool needs to extend 2 and 1/8 inches out of your jig. From the pivot point to where the gouge touches the wheel, it needs to be 7 inches.

I found this PDF online.