Unequal bevel on Sorby Bowl gouge

[scooby]

Thanks for suggestions. I wasn’t aware that changing the projection of the gouge from the holder made much difference but will happily give it a go. Is there a sharpening setup that uses a flat belt sander to avoid the concave bevel?

Theres nothing wrong with a concave bevel. Having a concave bevel on some tools (skew, scrapers, etc) will allow you to easily hone the edge with a diamond card to save going back to the grinder as often.

Sorby Pro Edge is a belt sharpener so will give a flat bevel. Its an expensive (but worth it imo) bit of kit. Or you could make an abrasive disc to fit on your lathe.
Again, nothing wrong with a concave bevel though. There are people who like/dislike both flat and concave.

Before I got a Pro Edge, I used a 6" grinder and I can't tell any difference (not talented enough) between flat and concave.

 

[Phil Pascoe]

Someone on this thread said to avoid a concave bevel.

I know experienced turners who won't use a ProEdge precisely because it doesn't give a hollow grind. The wheels at the club I doubt are much over four inches.

 

[Phil Pascoe]

Thanks for suggestions. I wasn’t aware that changing the projection of the gouge from the holder made much difference but will happily give it a go. Is there a sharpening setup that uses a flat belt sander to avoid the concave bevel?

I would think the grind in your picture perfect for a spindle gouge but too acute for a bowl gouge, certainly for anyone inexperienced. Try a grind with it not projecting so far, and when you find the perfect projection glue a stop on the base so that you can repeat it easily. Glue different stops for different grinds (label them), it saves messing about and more importantly tool steel - you can grind your perfectly shaped tool in one swing from one side to the other if the protrusion is identical to the one you used before.

 

[scooby]

As an add-on to Phil's advice of making a stop block, have a look here Sharpening gouges with a jig - Woodturning by Terry Vaughan

 

[Phil Pascoe]

I would think the grind in your picture perfect for a spindle gouge but too acute for a bowl gouge, certainly for anyone inexperienced. Try a grind with it not projecting so far, and when you find the perfect projection glue a stop on the base so that you can repeat it easily. Glue different stops for different grinds (label them), it saves messing about and more importantly tool steel - you can grind your perfectly shaped tool in one swing from one side to the other if the protrusion is identical to the one you used before.

Edit - I should have ideally rather than perfectly - perfect for you might be different from perfect for someone else.

 

[Bob Chapman]

They meant to avoid a concave cutting edge. The cutting edge should be straight or slightly convex. A concave BEVEL is pretty standard. I think your best bet would be to find an experienced turner and have lessons as soon as covid allows.

 

[Kerrowman]

Some success!

I have played around with the tool projection distance etc and have managed to match the grind I got back from the shop (without running the wheel).

Also after seeing a video mentioned a while back I have precisely cut a block of wood to set the jig distance exactly and repeatably (see pics).

Now when I come to sharpen I will waste minimal metal and get the shape I’m happy with, even if it turns out to be a little bit concave

 

[Kerrowman]

So thank you for all the helpful suggestions and comments

 

[scooby]

Good to see you're making progress.
The measuring block is a good idea, but don't forgot the wheel diameter will change over time. Not a big problem as (unless its getting heavy use) it won't decrease fast. Just something to keep in mind, you could either make a block that references off the face of the wheel to your jig arm pocket or use your existing one and check (periodically) to see if there is a light gap between the wheel and gouge.

Don't worry about that for now and just give the gouge a try.

 

[Jacob]

Some serious over-thinking going on?
I'd just have a go with it, then sharpen it freehand as best you can if needed and see what difference it makes. It's a learning curve - you don't learn if you don't do it and instead depend on gadgets/jigs/magic numbers.

 

[Phil Pascoe]

Sharpening freehand is a dreadful waste of expensive steel, no matter how efficient at it you are.

 

[Jacob]

Sorby pro edge plus gadgets £500?
Sorby bowl gouge £40 ish?

 

[Phil Pascoe]

A Sorby 447 is nothing like that money. The OP has a 1/2" and a 3/4" - that's near £140 a pair, besides any others.
Besides which he already has a jig, he's just not not using it properly.

 

[scooby]

Under and over pricing in one post..impressive.

Not that I'm suggesting its a must have item, but you can get the Pro Edge and all the stuff you need for turning tools for way less than that.