Fingernail grind

[V8-108]

Having decided to change the standard grind on one of my 3/8" bowl gouges to a fingernail grind I started doing a bit of research on how best to do it. Most of the information is out there, but the one thing that seemed to be lacking was reliable info on what sort of angle to grind back the top to give you the start. I guessed mine, and worked to that......it has turned out well and the chisel works just fine, but is there an angle I should have been working to or is it about personal choice (as seems to be the case with many angles on turning chisels!) Did I get it right by pure chance or will many different angles work?

Regards

Neil

[bodrighywood]

To be honest the angle is not really that important as long as it works for you. I haven't a clue what angle my tools are ground to, they work so they are. Sure some like to have specific angles but there are no golden rules as with so many things in craft works. As long as it is safe it is OK.

Pete

[Twisted Trees]

A good starting point is 45° ISH! 45° is a good angle in a lot of cutting operations with a gouge, so if you have nowhere else to go, go there! Mine were once about 45° along the wing, they are probably somewhere within 5° or so of that still. I have the bevel (bottom ) angle about 55° because I can and it fits many of the curves I am cutting.

Variation in your height relative to the lathe toolrest height relative to the workpiece all vary things and make tools quite personal, so it is hard to get a fixed answer, but 45 isn't a bad answer :-)

[julcle]

Niel,  As Pete and Pete says but I would just add that the top of the cutting edge along the flute should be a convex shape and not a concave shape which is a very easy condition for the beginner to end up with. Good Luck  --  Julian

[V8-108]

Just as a bit of a side thought on this subject.....is it worth keeping bowl gouges with the original grind? I have a virtually new set of Record Power chisels and the one I converted to the fingernail grind was a duplicate RP that I had. I'm not convinced that I want to convert the 3 newer bowl gouges yet, but suspect they will be slightly easier to use with the FN grind and probably more versatile? More experienced turners thoughts on retaining the original grind or conversion appreciated. Thanks in advance.

Neil

[Woodcrafts]

You might find the following useful as Stuart explains why various grinds work, when to use them and how to create them. It IS a lengthy video so you may want to skip some parts, but it is very informative.
https://www.youtube.com/watch?v=N7BjRcSDurM
Hope it helps,

[Bill21]

I’m not a prolific bowl turner but I read some time ago that it is worth having several bowl gouges with different grinds, the original grind being particularly useful for the bottom of bowls.

[Derek]

To be honest the angle is not really that important as long as it works for you. I haven't a clue what angle my tools are ground to, they work so they are. Sure some like to have specific angles but there are no golden rules as with so many things in craft works. As long as it is safe it is OK.

Pete

I am with Pete I have mine ground to what works for me never thought about the precise angle I use

[Bill21]

The only time many people bother to check the angle is when a pro turner helpfully provides this information about the grinds they use on their tools. Just because the “unknown” angle a turner uses works for them doesn’t mean they aren’t missing out on something. I couldn’t tell you the present angle on my gouges but I do reference them against accepted angles from time to time. As an example, my spindle gouge worked absolutely fine with “my” standard grind but worked so much better when I replicated the grind used by Cindy Drozda.

Keep an open mind and don’t get set in your ways.

[bodrighywood]

I agree with you Bill though the open mind includes those who think that what the 'experts' use is right.

Pete

[Bill21]

I agree with you Bill though the open mind includes those who think that what the 'experts' use is right.

Pete

Yes, it’s been said more than once that some of these grinds are not for the inexperienced!

[Twisted Trees]

As an example, my spindle gouge worked absolutely fine with “my” standard grind but worked so much better when I replicated the grind used by Cindy Drozda.

Keep an open mind and don’t get set in your ways.

I agree with you Bill, I do every now and then think about it and "reset" my grinds then I sort of measure and engineer a particular grind, often it is because I have been careless and tried to cut a piece with a nail or stone embeded....

Specialist cutting as done by Cindy does require a specialist grind, which is why bowl and spindle gouges wear out quicker, so that you can have a new one, then experiment with weird shapes on the old ones 

But I have yet to see a blank wielding a protractor and until I do 13 to 18° = 15 and 42 - 48° = 45 etc....

[Twisted Trees]

Just as a bit of a side thought on this subject.....is it worth keeping bowl gouges with the original grind? I have a virtually new set of Record Power chisels and the one I converted to the fingernail grind was a duplicate RP that I had. I'm not convinced that I want to convert the 3 newer bowl gouges yet, but suspect they will be slightly easier to use with the FN grind and probably more versatile? More experienced turners thoughts on retaining the original grind or conversion appreciated. Thanks in advance.

Neil

Yep, one mid size steep angle traditional grind covers that need the others are all some form of fingernail as it is more flexible, if you find yourself cutting 1 shape repeatedly then a specialist grind for that shape is good, but for most "more versatile" is the winner.