McNaughton Center Saver Question

[Mike Goetzke]

Little over a year ago I bought the kit with large and standard blades. I have only cored a few bowls but plan to do several more. I see they estimate 4-8", 6-10", 8-14", and 10-18"+ for the micro, mini, standard and large blade sets respectively.

I was wanting to buy some individual knives to make smaller cores (Lee Valley has free shipping right now). But, I know from my current large/standard sets that the sets seem to overlap. In other words the radius on some of the std. seem to be the same as the large. If I wanted to compliment my current arsenal to produce smaller cores I'm sure I don't need to buy full sets of mini and micro - hopefully just one or two more knives???

Hopefully someone has experience and figured this out. Appreciate your opinions.


Thanks,

Mike

[Reed Gray]

I can't remember for sure, but think there are 4 sets; large, standard, small, and micro. I do 90% of my coring with the standard set and the medium curve blade. If I was doing sets like Mike Mahoney, then I would use the mini to squeeze out the most from a piece of beautiful burl. For standard bowls, you don't need them. I don't core less than 10 inch diameter and 4 inches deep. I end up with too many tiny bowls which do sell, but take a surprising amount of time.

robo hippy

[David Gilbert]

Reed,

I am interested in doing sets like (well similar to) Mike Mahoney where there are lots of bowls nested together. I have the standard set of blades. Each of the blades has a curved diameter like 7, 11, & 14". If I start by coring out a 7" bowl and want the next bowl to be about 8" in diameter, there is a problem. When I move the starting point out it doesn't seem possible to use the 7" blade to cut an 8" bowl with the same profile as when the 7" blade cuts a 7" bowl. The bowl will be wider but also flatter. Do Mike and the others who do these amazing nested sets have a whole series of blades where the blade diameters increase uniformly so they can cut out these uniform bowls?

Cheers,
David G

[Reed Gray]

If I was going to make a personal set of blades. I would start with about a 3 inch radius, and go up from there in 1 inch increments. Given the shapes of the feet on the bowls, it is difficult to move in 1 inch steps though, unless you are making 'earthquake' indicator bowls with round bottoms. You still need a flat space for your chuck to grab onto. With a burl, most have a convex top, so that does make the process easier. Starting with a standard bowl blank, you don't get as many cores. Mike does explain a bit about that in his video, I explain some of that in my video as well, which is up on You Tube. Only other consideration is that the smaller blades have a narrower tip so they remove less wood.

robo hippy

[Ralph Lindberg]

The article in the AAW journal a few years ago on coring had a supplemental PDF that might be of use, this PDF is (was?) available on the AAW web-site.
Among other things this PDF showed the radius of each blade and showed an overlap between blades. I don't have it in my hands, but as I recall the "small" and "medium" blades in the large set had the same radius as the "medium" and "large" blades on the standard set. Only the large blades are longer.

[David Delo]

American Woodturner Feb. 2013 Vol 28 No 1 is the article I believe Ralph is referring to.