The more I turn the more I think that the

[Arlin Eastman]

way or degree of the gouge really does not matter.  Just as long as you use the bevel on the wood.

I do not think it ever needs to be exactly 60* nor 40* nor 32* or any other if they are 5* to 10* off of whatever you like and use the bevel you should get a great cut.

I know some bevels on bowl gouges like something of 80* cuts well on the bottom but I have used my 60* which is +/- *'s will work just as well with a little more finesse or sanding.

I have seen neg-rake scrappers that look like skews do good work on inside and outside of bowls and other turnings and if they are not exactly 60* - 80* they will still do a great job just as long as it has a burr on it.

Let me know if I am wrong or not, but it sure seems to work that way when I do it.

[SceneryMaker]

My opinion on the subject:
The wood only sees an edge and acts accordingly. It has no idea what angle the handle is or the shape of the tool. It's the turner who has to present the tool to the wood correctly. The shape of the tool makes that presentation easier or harder in some cases but the only rule that I stand firmly by is this. "If it's almost sharp, it will almost cut."

In other words, I agree with you.

[MichaelMouse]

My opinion on the subject:
The wood only sees an edge and acts accordingly.  It has no idea what angle the handle is or the shape of the tool.  It's the turner who has to present the tool to the wood correctly.  The shape of the tool makes that presentation easier or harder in some cases but the only rule that I stand firmly by is this. "If it's almost sharp, it will almost cut."

In other words, I agree with you.

Of course, dragging a "bevel" will do nothing but burnish the wood, so some form of clearance angle is imperative.  As that angle opens, the wedging of the shaving will take a bit more energy - increase in pitch angle - but nowhere near what actually dragging non-cutting metal will. For a visual illustration of the terms, see Hoadley or http://homepages.sover.net/~nichael/nlc-.../caop.html


My preference for broader sweep gouges skewed and taking broader shavings allows a bit more of the edge to slice as the work slides by, but also leads me to use longer bevel grinds than the cylindrical gouges are really capable of taking.  In theory that should make the edge more fragile, but in practice, as said, the wood sees only the edge.  A little longer portion with traditional forged tools, which is nice.

[Arlin Eastman]

Of course, dragging a "bevel" will do nothing but burnish the wood, so some form of clearance angle is imperative.  As that angle opens, the wedging of the shaving will take a bit more energy - increase in pitch angle - but nowhere near what actually dragging non-cutting metal will. For a visual illustration of the terms, see Hoadley or http://homepages.sover.net/~nichael/nlc-.../caop.html


My preference for broader sweep gouges skewed and taking broader shavings allows a bit more of the edge to slice as the work slides by, but also leads me to use longer bevel grinds than the cylindrical gouges are really capable of taking.  In theory that should make the edge more fragile, but in practice, as said, the wood sees only the edge.  A little longer portion with traditional forged tools, which is nice.

MM

Most of the time you always lose me with the long parts of it.  So you agree with it and just like a bit longer bevel?  Correct????

[MichaelMouse]

MM

Most of the time you always lose me with the long parts of it.  So you agree with it and just like a bit longer bevel?  Correct????

Yes and no.  Think of St. Roy of Underhill's "edge and wedge."  You cut across the grain with an edge, along by a wedge.  Think of whittling, where you cut across with the edge almost vertical, then lower the pitch angle to wedge the shaving along the grain.  If you've got a Buck, or some other cutting knife, with steep bevels, you can cut across the grain, but can't whittle worth squat, as if you had a nice Camillus or Case with almost no edge bevel.  Same with turning.  Since it's the pitch angle that counts, a smaller sharpness angle will peel better than a large one when using the same clearance angle.  Remember, "riding the bevel" for a good peel is a myth.  Lower clearance angle is what makes it seem possible, but zero clearance angle heats and burnishes rings, right?

We can also take advantage of a couple other factors on the lathe.  First, as with whittling, when the knife is drawn through the cut, things are smoother. The lathe turns, continuously drawing our edge through our cut.  Second, skewing the edge effectively lowers the pitch angle, and we can do that, as well,  Broader skew angles make for smoother surfaces, but a cylindrical gouge makes it near impossible to get one, except by forcing us to grind and cut with the wings.  Broader sweeps may be ground fairly steep and still get useful skew angles, but the real money comes from the combination of longer bevel, shallower gouge, and skewing both along the gouge path, progressively deeper when the broad belly allows.

[Arlin Eastman]

Good grief you did it again to me. 




It seems what you are talking about primarily is a skew???   Or are you talking about having more then one tool with different bevels????


Which part is Yes and which part is No????

[MichaelMouse]

Good grief you did it again to me. 




It seems what you are talking about primarily is a skew???   Or are you talking about having more then one tool with different bevels????


Which part is Yes and which part is No????

Skew is a verb.  See the URL I included about skewing the edge.  The edge is still the edge, skewing as it is advanced simply lowers the effective angle.

So, agree that an edge is an edge, but the desired presentation is the key to setting bevel length for the task to be performed.  The more climbing grain or end grain involved, the lower the desired edge presentation to sever cleanly.  In a faceplate presentation, we have two areas of climbing grain guaranteed, which makes long bevels desirable because they wedge less and ridge less when presented to take a wider shaving.

[attachment=18652]

Static photo, and you can see I have the handle a bit low.  The part of the gouge which was cutting is obvious, swept clean by shavings and edged with a bit of dust.  

[attachment=18653]

This shows skewing the gouge and allowing the broad curve to deepen the cut as the tool is advanced.  Double skew!  A cylindrical gouge would have a hard time engaging the work with that big an edge.  Curves too fast.  Thus my love of what used to be, not what is ground weirdly to try and imitate it.

[Arlin Eastman]

OK I get it I thought you were talking about the Skew tool not skewing to the wood.