Coring with just a blade?

[Gabe Latner]

I mainly turn bowls that are 9" or smaller. Sometimes, I'm lucky enough to get blanks that are deep enough that I could core out one extra bowl, and feel bad about turning it to shavings.

I'd rather not drop $500 on the full McNaughton system, but I can pick up one of the curved blades for $70. I've seen videos of people making "cone" cores with, e.g. the Sorby Slicer, without a specialized tool rest. Can curved blades be safely used the same way?

 

[Ron Solfest]

I have a McNaughton system. I don’t think I’d be willing to try one of the curved blades on a regular tool rest with out the capturing mechanism to hold the handle from coming up violently and wrestling it out of my hands. Not that it couldn’t be done, just I don’t think it could be done safely by me

 

[Kevin Jesequel]

No. With a straight blade, the force is directed straight down in line with where the blade sits on the tool rest. With a curved blade, the downward force will be to the right of where the blade sits on the tool rest and will cause it to twist and catch without proper support. I can’t imagine the result being anything but catastrophic. If you are patient and keep your eye out, you can get a used set for a good price. Likely to be in “like new” condition too

 

[hockenbery]

Can curved blades be safely used the same way?

No - without using a trap gate torque and rubbing the wall will make it impossible to control the tool and it will surely bind in the kerf after 2-3 inches.

the stewart slicer is just a big parting tool. As long as you keep some clearance for the shaft of the tool, cut at center or a tiny bit below, and clear the chips if they don’t feed out you can control the slicer at a pretty good depth 6“ easily. Much more if you develop A comfort with the slicer.
You can core cones or rings from blocks.
the Ellsworth straight tool will do the same job but needs a wider kerf.

 

[robo hippy]

I have cored thousands of bowls. I would not even dream of attempting to core a bowl with the straight cutter without the vertical gate. I guess you could make one, but I would not go with wood. At least not wood dowels. Wood blocks maybe....

robo hippy

 

[Dennis Weiner]

In regard to the oneway corer, Never Ever EVER ...... core a bowl with just the knife, Always use both the knife with its paired finger.
A friend of mine didn't use his for a number of years and forgot to put the support finger in and slightly bent that heavy-duty thick steel knife. The two arcs no longer clear each other so he can't get a complete cut. Using the knife alone will cut fine for a few inches in but will bounce around or grab the bowl blank as the cut gets deeper and deeper into the wood as the leverage against it increases. (just like trying to cut way off the tool rest)

That was a 200-dollar mistake.

 

[JeffSmith]

I’m with Robo on this. I use the Macnaughton straight cutter a fair amount to pare off a platter or lid from large blanks before coring. It may be possible to use it on a 3” spindle (or smaller), but I’d still recommend taking the few minutes to set up the turret even for smaller stuff. I’ve sliced lids from blanks as large as 20” and often wind up breaking out a hand saw to finish the big stuff. I do make sure to widen the kerf a little as I go just to help avoid the blade binding in the cut.