# bowl coring



## Gary0855 (Aug 3, 2010)

Anyone have a bowl coring tool? Pros, Cons?
Suggestions on which brand? Anything??

Thanks


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## Dave Paine (May 30, 2012)

I purchased a used the McNaughton Centre Saver set in July.

I have not yet used the set. I have since acquired a number of log sections, but have not got around to cutting any of them into a section large enough to try the saver.

This is what the McNaughton set looks like. Mine is the large set, but has additional knives.

http://www.leevalley.com/us/wood/page.aspx?c=&p=49128&cat=1,330,49232&ap=1

My set has the handle and the extension.

The knives have carbide tips which are about 1in long. So if sharpened a lot would eventually need new tips welded on.

The handle is very heavy. Two allen headed screws to hold the knife. A little finicky. The screws tighten onto the edge of the knife.

From what I read a potential con of any brand is that the cutting method takes a lot of power, so not good for lathes with smaller motors. The McNaughton set recommends 2HP motor.

The tool gate uses a 1in post. Another potential issue for some lathes which use a smaller post.

Another con of any brand is that the knife curve determines the diameter of the bowl. No surprise.

I am expecting a learning curve. I read it is easy to bust out the back of the blank while learning how to use the tool.


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## Dave Paine (May 30, 2012)

I found some useful links.

This one discusses the different systems.

http://www.morewoodturningmagazine.com/articles/coring.pdf

This one discusses using the systems.

http://www.woodturners.org/links/coringarticle-Joe.pdf


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## Horatio (Apr 4, 2012)

The system fascinated me though, because I harvest my own wood, its not really an issue. I expect when purchasing a blank, one would want to get as much out of it as possible. For me, its a matter of cutting and making a mess is all.


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## duncsuss (Aug 21, 2009)

If they weren't so expensive, I'd buy one in a heartbeat ... I've had 3 or 4 bowl blanks with drop-dead-gorgeous figure, and I was nearly in tears as I hollowed them out and the shavings fell to the floor.


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## DaveTTC (May 25, 2012)

Just my 2 cents worth. Could you save the centre by using a swan neck chisel ?


I know duplicating the cut may not be so simple. I have no fancy chisels yet so can not try it myself.

Dave The Turning Cowboy


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## Gary0855 (Aug 3, 2010)

Thanks for the links Dave, according to one, there may not be one for a mini lathe....bummer

I have the Jet mini lathe and can only turn up to ten inches, it be nice to core the small ones too. The amount of shavings is insane.


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## Dave Paine (May 30, 2012)

DaveTTC said:


> Just my 2 cents worth. Could you save the centre by using a swan neck chisel ?
> 
> I know duplicating the cut may not be so simple. I have no fancy chisels yet so can not try it myself.
> 
> Dave The Turning Cowboy


It sounds easy to just use a curved tool, but in addition to the tool, it seems a method to support the tool is also required. This is the tool gate which contains posts to guide and support the tool.


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## DaveTTC (May 25, 2012)

Dave Paine said:


> It sounds easy to just use a curved tool, but in addition to the tool, it seems a method to support the tool is also required. This is the tool gate which contains posts to guide and support the tool.


Yeah I can see you could get in trouble with the swan neck if it got caught ........ Ouch

Dave The Turning Cowboy


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## Dave Paine (May 30, 2012)

*Using the McNaughton centre saver video*

While looking for something else, I came across this excellent video on using the McNaughton centre saver.

This is an hour and 11 minutes, but the presenter spends the time needed to explain how to use this tool, and an impressive demonstration. I recommend this for anyone wanting to get into bowl coring.

I had wondered how to figure out the entry angle. Now I know at least one way. Works for Dale, I hope it works for me when I start to use the tool.

https://www.youtube.com/watch?v=mS2yIb0HAU4


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## cuerodoc (Jan 27, 2012)

I have the Mcnaughton saver and have used it more than once. It does work with my lathe (1.5 Hp) although can bog down if feeding too fast. Guess if you have a big PM or other lathe, it might be as easy on the dvd, plus I think I use lots harder wood than I've seen on the demos. It takes some practice to visualize where the blade is going--the Mahoney dvd is very helpful.
On a side note I also have the Sorby slicer (bought a fancy Sorby set-handles and extensions, tips-- on ebay a while back) and basically it's just a looooong parting tool. Only good for conical cuts if wanting to core and guarandamteed  to hang.
Dave H


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## Dave Paine (May 30, 2012)

*2 out of 3 ain't bad*

Sounds like a song.......

On Friday I tried my McNaughton Core Saver for the first time on a walnut blank, part of a stump I helped my friend cut up earlier in the day. As green as it gets.

About 12in overall diameter and about 8in deep.

I had watched the video in post #10 a couple of times. If anyone wants to try using the McNaughton system, I highly recommend the video.

Determining the angle of entry is critical.

I got lucky with my first attempt, the knife tracked where I wanted.









The core next to the bowl. I will save this, not sure what I will make with it, perhaps small bowl. Time will tell.









Today the friend who gave me the walnut came up with two cherry bowl blanks.

The first one we did not get the angle of entry correct. Too shallow and we ended up in the tenon. He will salvage the blank, but needs to add a new bottom for the large portion.

The second one we spent more time on the angle of entry, measuring 3 times, then adjusting to be a bit more conservative. This one tracked as desired and he got two nice thick bowls he wanted.

My friend left and I forgot to take pictures.

My McNaughton system was purchased second hand. It does not have the U bracket to hold up the knife, so it does need a lot of care to prevent the knife from dropping.

I think I will make a jig to hold up the handle, like the bottom part of a captive bar system.

All in all, we were happy with the first 3 tries.

Now I am off to attempt the second core on this walnut blank.


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## Dave Paine (May 30, 2012)

"Murphy" stopped play on the second attempt. My tenon was close to the minimum range of the #3 jaws.

I started to make the cut, and as the knife made contact the bowl came off the chuck.

So now I have to make a jam chuck so I can turn off the tenon and either make a bigger one, losing some depth, or glue on a block of hardwood and then turn this.

I have sealed the blank while I prefer to make another attempt, hopefully without "Murphy" being around.


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## Manuka Jock (Jun 27, 2011)

The only one I have used , and used quite often , is the 



specs here Bowl Saver.
It worked well on a 2hp DVR powered lathe . I can't make any comparisons with other systems tho.

The one I used was equipped with the lazer guide , it made life easier


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## john lucas (Sep 18, 2007)

I have the McNaughton. It does the job but the learning curve is difficult in the beginning. I get lots of free wood so I seldom use it. I did make the jigs necessary to make my own bars and cutters. 
The Oneway system is far easier to use but quite a bit more expensive. 
There is a great article in American woodturner on Coring and how to make the entry cut which is crucial. If your an AAW member you can look it up online. If not, well join, you get access to every issue from the very first one. Plus you'll get all the new ones and access to the online beginners magazine.


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## DaveTTC (May 25, 2012)

nice cores Dave


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