tool grinding question

[Scott Loven]

Do you/should I you remove the bur after grinding a lathe tool?
How do you know when your tool is sharp?
How do you know when to resharpen?
can i regrind a traditional grind bowl gouge into one with an irish grind?
I have Bill Gs DVD and the oneway jig, but have yet to FINISH a bowl. I started two, but they broke off in the chuck.
Scott

[Dennis Peacock]

To answer your question for me only:

1. I do not remove the bur. I simply go to the grinder and "touch up" the edge and get back to the lathe.
2. The tools will produce dust or be difficult to cut the wood. In a short time, you'll learn the feel of when the tools is "getting" dull enough to need a fresh edge to cut with.
3. Yes, you can regrind any bowl gouge to any type grind that you choose. I turned a standard grind bowl gouge into an Ellsworth Grind gouge in a matter of minutes on the grinder. You can even grind and old parting tool to make it into a bowl scraper.

Last but not least? What do you mean when you say they broke off the lathe? What's your mounting method?

I have learned that you can break a bowl off the chuck by over-tightening the chuck jaws around the tenon on the bottom of the bowl. DAMHIKT!!!:o
In the same token, I've also split a bowl by expanding the chuck jaws too tightly against the recessed tenon on the bottom of a bowl. :o

After a while, you learn how much to tighten in order to avoid snapping a bowl off the lathe.:rolleyes: ;)

[John Miliunas]

Scott, although I'm not nearly as accomplished with the spinny thing as Dennis is, he pretty much covered my routine on sharpening!:) I have found that, quick trips to the grinder are much more preferable than waiting too long and then having to spend a lot more time at the grinder. I also note that, in doing so, my results (such as they are:rolleyes: ), typically end up a bit more consistent. Really not a whole lot different than using a utility knife beyond its point of reasonable. You end up doing more "chopping" than cutting, then, when you switch to a new blade, all of a sudden, you're using more pressure on the tool than is necessary. Good advice, IMHO. :) If, for whatever reason, I end up putting a "new" edge on a tool, then I'll take a moment and clean off the burr a little bit. I simply take some 400 paper and wrap it around a small dowel and hit the burr side with it.

Also, ditto on overtightening when expanding the chuck into a recess. Been there, done that, didn't get the T-shirt!:rolleyes: :cool:

[Bill Esposito]

I dont remove the bur after grinding EXCEPT for the final pass or when I've got some real tough end grain to finish cut.

You really need to compare a sharp tool to a dull tool so you can see the difference. A dull tool will cut, but not as easily. The best way to tell if your tool is sharp is to sharpen it, look at the edge and make sure there are no reflections from flat spots (might need incandescent light), and then do some turning. It should be easier now that the tool is sharp.

What will probably happen next is that you'll start having trouble with your turning. You'll think to yourself that this wood is really hard...but wait, remember a while ago when it was cutting like butter? Time to take another trip to the grinder.

Lately I've been using a diamond hone between grindings. It extends the time between grindings and really keeps the tool sharp.

And yes, regrind away. Just remember to grind that edge and look at it for flats. When I do a first grind, a regrind or and extensive grind, I usually look at the edge through an eye loupe (maybe because I'm getting blind). That's how I found a flat on my Woodcut Proforme tool that shouldn't have been there.

[John Nicholas]

Do you/should I you remove the bur after grinding a lathe tool?

I always remove the burr. When you place your gouge on the wheel, a small burr is thrown up in the flute. You can take a fine file, diamond hone, slip stone or other tool and quickly remove that burr. Just be careful not to round the line of the flute into the bevel.

What about honing the bevel? That is something else. But in doing that you are not removing a burr.

John :)

[Dick Strauss]

Folks,
a friend of mine showed me a neat trick to hone the edges of tools. First he cut a bunch of 6" discs of MDF. Then he stacked and glued them together to make a cylinder. This cylinder was mounted on a face plate. So at this point you have a giant face-plate-mounted MDF cylinder. From this point you turn various profiles in the MDF to match the shape of your turning tools.

Once you have the profiles, you simply rub the tools against the mounted MDF cylinder to hone the edges. This must be done from the opposite side of your lathe or your lathe must be reversed to prevent cutting/catching the wood (the MDF has to rotate from the bottom towards the top as you face the MDF). MDF has abrasive qualities that makes it great for honing. You can hone both the inside and outside edges of turning tools if you have the right profiles. You can also use it for chisels, planes, or just about any tool!

I'll post pics if this note isn't clear...

[Scott Loven]

To answer your question for me only:

1. I do not remove the bur. I simply go to the grinder and "touch up" the edge and get back to the lathe.
2. The tools will produce dust or be difficult to cut the wood. In a short time, you'll learn the feel of when the tools is "getting" dull enough to need a fresh edge to cut with.
3. Yes, you can regrind any bowl gouge to any type grind that you choose. I turned a standard grind bowl gouge into an Ellsworth Grind gouge in a matter of minutes on the grinder. You can even grind and old parting tool to make it into a bowl scraper.

Last but not least? What do you mean when you say they broke off the lathe? What's your mounting method?

I have learned that you can break a bowl off the chuck by over-tightening the chuck jaws around the tenon on the bottom of the bowl. DAMHIKT!!!:o
In the same token, I've also split a bowl by expanding the chuck jaws too tightly against the recessed tenon on the bottom of a bowl. :o

After a while, you learn how much to tighten in order to avoid snapping a bowl off the lathe.:rolleyes: ;)
The tenon broke off the bottom of the bowl, both times. The broken tenon stayed in the chuck.
Scott

[Travis Stinson]

Scott, are you making sure you have a good shoulder turned on the tenon for the face of the jaws to rest against?