Sorby Belts, Pt II

[John Grace]

The standard Sorby belt assortment stops at 240 grit. I see other abrasive companies offer up into the several thousand. For those of you who use the pro-edge sharpening system what grit do you typically stop at and why? The question is relative to bowl gouges and skews, thanks...j

 

[William Rogers]

I don’t sharpen my bowl gouges using the Sorby. The extension needed for bowl gouges is a lot using the Sorby. I use the Hannes vector jig for bowl gouges, I use the Sorby for my skews, scrappers, and roughing gouges. The highest grit I usually use is 220. I hone my skews and burnish my scrapers. The edge is fine for my spindle gouges. I have those high grit belts, but never use them. I do use a 40 grit for re-shaping and a 120 grit sometime.

 

[Bernie Kopfer]

The standard Sorby belt assortment stops at 240 grit. I see other abrasive companies offer up into the several thousand. For those of you who use the pro-edge sharpening system what grit do you typically stop at and why? The question is relative to bowl gouges and skews, thanks...j

I use the Sorby system but have been unable to find ceramic grits higher than 120. 120 is good but in my experience higher would be a bit better. But the 600 or more grits are usually used for knife sharpening.

 

[Bill Alston]

I use an Axminster Pro Edge that takes the same size belts as the Sorby. Here in the UK I often use 800g blue film belts sold by Axminster. Normally only on spindle gouges or scrapers though prior to pressing a burr with carbide.



Here in the UK you can normally get custom belts made, albeit with a minimum order of 10 belts.
I also make up my own belts from time to time. I’m not sure how fine abrasive rolls are commonly available though?

 

[Bernie Kopfer]

William could explain what you mean by” the extension needed for bowl gouges”.

 

[William Rogers]

William could explain what you mean by” the extension needed for bowl gouges”.

Bernie, with the Pro Edge you need to have couple inches plus the setting the tool to the desired sharpening angle. Looking at the picture below you see about 2” extension on the 45 degree setting and a lot more as the angle decreases. With the Hannes Vector jig I can use all the way down to 1/2” remaining flute regardless of angle. That is a lot of tool life left.



Also Supergrit has 220 ceramic Sorby belts.

Supergrit® Abrasives: Search

 

[Bill Alston]

I believe some have got round this by grinding a flat on the top of the tool between the end of the flute and the handle?

 

[William Rogers]

I believe some have got round this by grinding a flat on the top of the tool between the end of the flute and the handle?

Yes, I tried this with the wolverine system, but hand grinding a flat is never precise. You get off any and this affects the shape of the grind. Robust tools does provide a flat the length of the tool. With the Hannes I get the same results time and time again and prefer the way it shapes the tool.

 

[Doug Freeman]

I believe some have got round this by grinding a flat on the top of the tool between the end of the flute and the handle?

Yes, I do this. Sure the flat isn’t perfectly parallel to the flute tops, but it doesn’t affect performance IMO. The grind will change slightly once the jig is clamping on the new flat, but then it is done and very repeatable. Running a coarse diamond hone across the machined area will flatten it out for repeatability.

 

[Bernie Kopfer]

Thank you William, your explanation was really clear. And I appreciate the link to Supergrit

 

[Bill Alston]

Part of the problem with the gouge jig on the Sorby, is that it was originally designed for use on the Tormek. Before the patent ran out the jig was manufactured and supplied by Tormek. When the patent ran out Sorby started making their own. The Tormek jig is fully adjustable for angle but Sorby generally advised against this. I’ve read that adjusting the angle, together with reference to the Tormek instructions, some turners have had favourable results.

For reference, the Tormek jig has a black plastic knob and has index marks for repeatable angle adjustment.
The Sorby jig has a red anodised knob and is I think bereft of any angle reference?

Edit: Another obvious difference is that the Tormek jig is used directly on the (12mm diameter) fully adjustable guide rod.
The Sorby modified version is used with a Boss that slides on a fixed 1/2” guide rod. The Tormek system offers much more flexibility in the way in which it can be adjusted to suit the grind required.

Edit 2: The Axminster Ultimate Edge belt grinder uses a fully adjustable 12mm guide rod to take advantage of the many different jigs available for the Tormek and other wet grinders on the market. It’s also variable speed with forward and reverse.