_ Bowl "coring" tools/system ?

[Joe Watson]

Ive seen a bowl coring system (McNaughton) and was wondering if it (or any other brand) really works ?
Any brand that you recommend (i have a 12" swing on the lathe) ?

Are you limited to the depth of the bowl core you remove (you can not control it) ?
eg: removing a core that is 4" dia, then the depth would be 3" (or what ever). That depth has a standard relationship to the dia ?
Can you bend the "cutters" to create different depths ?

Right now i dont have access to alot of "log wood"/bowl blanks. So what i do get just kills me with all the "waste" when removing the inside. So i started to look into the coring system. I figured even if i was to make a shallow 8-9" bowl, i could use one of the coring system to remove a smaller 4-5" portion (being the main bowl will be shallow) and use that for something else.

Thanks for any help.


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[Harry Robinette]

Joe
I use the McNaughton system and love it. Everyone says to use the kind they have I say get the one thats going to do what you want it to do. McN system has different size blade packages which makes it much easier to update if you update your lathe. This system is a LITTLE harder to get use to, but it's not as hard as some people say. If you get the McNaughton system you'll want to get Robo Hippys DVD it helped me allot.

[Steve Kubien]

First thing...don't start going around bending the coring blades. You are asking for trouble here.
Secondly, they all work. I have had the McN, hated it, returned it, though considering trying again now that I am older and supposedly wiser. I had the Woodcut and loved it except for the maximum size core your could take (wouldn't be a problem for you). Currently use the Oneway rig and unless you sharpen the cutter after each core, it is becoming a pain to use (thus I am considering the McN again, of the new, larger Woodcut once it is available).

Ummm, I blogged about all of this a few months back. The link to the blog is in my profile if you are interested.

[Richard Allen]

There are three shaped cores you can make.

A curved shape. That curve can have a small or large radius but the curve needs to be part of a circle. These coring systems tend to need a LOT of power. You can sharpen and work slowly with a lower powered lathe but you may find the process tedious. You can easily stall a 1 HP lathe with one of these coring systems.

A straight cone core. This is basically a parting tool. Note the cutter needs to open a kerf which permits the blade holding the cutter to follow the cutter (just like parting off a spindle you will likely need to widen the kerf as you go).

Straight sides and flat bottom. These are primarily small cores. You start off by making a plunge cut straight in (parallel with the bed of the lathe) then use a device called a bowl saw which is used to cut the core out perpendicular to the bed of the lathe.

[Reed Gray]

I prefer the McNaughton, and it is the only system to have blades made specifically for the mini lathes. There is a bit of a learning curve with it. The Woodcut is also a nice little system, and the big blade is a 5 inch radius.

As for horse power requirements, they all cut like scrapers, and the tips are all (except micro McNaughton) about 3/8 inches wide. If you can take a 1/2 inch scraper and make cuts with it, you shouldn't have any problems. I wouldn't want less than 1 hp though.

robo hippy

[Gary Max]

Personally--save your money. Been there and not a fan of coring systems.

[Russell Neyman]

There must be a coring/saver system that doubles as a hollow form system, too. Maybe not the cutting head, but at least the guided tool part of it. Anybody?

[Josh Bowman]

Joe your picture(avatar) freaks me out every time I see it!!!
Anyway, I have the McNaughton system and really like it. Reed Gray has a great DVD that works you through the hard stuff. I also have Mike Mahoney's DVD and like it as well. Mike's DVD makes it look deceptively easy, while Reed Gray's is more realistic. Both are good though and worth having. If your going to buy just one, get Reeds.
I'm a novice with the thing, but manage to get some very nice cores. There is a skill set here, since 1)the tools tend to pull themselves into the core and 2)they tend to go toward the chuck. The hard part is mastering the gentle guide of the tool and determining where the tip is, as I did not in one of my first corings, see 2nd picture.

[Russell Neyman]

I've only seen the results of this system and have not used or personally seen the process in action. It's my understanding that it takes a light touch and plenty of patience. It seems to me that this is best used with some very special burls or hardwoods where saving the material has a greater value than time invested.

So, looking at Josh's two photos of nested blanks: It seems to me the process would be to (a) cut a core, taking the time to finish the inside and lip of the round bowl before moving forward, (b) cutting the next core, essentially roughing the bottom of the semi-finished first bowl and the inside of the next one, then (c) repeating the process until you've used the entire blank. At that point you've got to re-mount all of the cores in soft jaws so that you can finish the outsides and bottoms. Is there another way to do this?

My friend, Dave Schweitzer (D-Way Tools) displays nested natural edge bowls he produces using a coring system, and it seems to me he must either use a vacuum chuck -- something that I simply don't trust nor do I want to try it -- or hand sand the outsides to achieve the result. He might also be simply creating the "natural barked edge" with a Dremel and torch. He does really creative work, and is quite innovative in how he gets finished results. I've posted a photo of his work here. I should add that I'm encouraging him to add a gallery of his work here. To my way of thinking, Dave is one of the top woodturners in the United States.

I love the idea of a wood-saver/coring system, but wonder if it's worth the bother.
nb1-lg.jpg

[Josh Bowman]

So, looking at Josh's two photos of nested blanks: It seems to me the process would be to (a) cut a core, taking the time to finish the inside and lip of the round bowl before moving forward, (b) cutting the next core, essentially roughing the bottom of the semi-finished first bowl and the inside of the next one, then (c) repeating the process until you've used the entire blank. At that point you've got to re-mount all of the cores in soft jaws so that you can finish the outsides and bottoms. Is there another way to do this?

The process I use is to shape the outside of the largest bowl, then core the smallest, I then reverse it in the recess it came from as a jam chuck and cut a tenon, then I cut the next core and reverse it and cut the tenon, etc until I run out of room against the outside core.
Reed has a better way, where you core the largest, then rechuck that core using a recessed tenon he's cut in the blanks top at the beginning and cuts another recessed tenon on the bottom of that core and reverses it again, until he's down to the smallest bowl. Either way it takes about 2 or 3 minutes to cut the core and a minute to do the tenon. My McNaughton does a better job of shaping the outside of a bowl than I do, when the core is cut, the rough bowl is ready for drying, no recutting is needed.
Time is not the real issue, the real issue is $$$$. These things are expensive! And even though I got mine at a good price, I could have bought a lot of wood for the expense. One side benefit is it cuts way down on the mess.....on the other hand.....brooms are cheap.

[Richard Jones]

.....Reed Gray has a great DVD that works you through the hard stuff. I also have Mike Mahoney's DVD and like it as well. Mike's DVD makes it look deceptively easy, while Reed Gray's is more realistic. Both are good though and worth having. If your going to buy just one, get Reeds.....

Ditto to that.

Like anything else, practice makes you better. I am really enjoying my McN, and I use my Monster laser with it. I am currently working on a system whereby the tool post is lined to a specific point, depending on bowl dia. and depth. Anyone else doing something like this?

Rich

[Reed Gray]

If you are turning green wood to final thickness, I prefer taking the biggest core first. If you are doing twice turned bowls, the way Mike does, then it makes some sense to take the smaller ones out first. Either way works.

robo hippy

[Alan Zenreich]

So far I've had very good results with a Woodcut Bowl Saver... I've used it on my 16" machine and it would work very well on a 12" lathe

[Steve Kubien]

Alan, you know, I'm still kinda regretting selling you the Woodcut. I like the capacity of the Oneway but prefer to use the Woodcut. They cannot introduce the larger version fast enough to suit me.

[Scott Hackler]

I bought a used McNaughton system and got a hold of Reed Gray and bought his DVD regarding the McNaughton. His video helped a bit. I liked seeing someone do it before I jumped right in. I cored two sets of Cedar bowls and it went without a hitch. The third set was being cored out of green elm and I finally found something that would STOP my lathe! I bound up one of the knives and it not only stopped the lathe but bent the knife! I was able to bend it back in a vise though. This system I bought is an early version and doe NOT have the fancy looking Mark 8 rest.

Each of these systems will work to core bowls, but the key is knowing HOW to use them.