# Centering Question



## Johnturner (Apr 13, 2015)

I have a chunk of box elder burl that I want to make into a natural edge hollow form. It is about 4x4x6. The bottom is pretty square and finding center will not be a problem but the opposite end is where in burl shows and it is very bumpy. I am turning between centers to put a tenon on the bottom. What is the best way to find center on a very rough and bumpy surface. A lot the sides are not the same some are taller than the others.

Thanks for listening.
John


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## Schroedc (Apr 13, 2015)

I'll eyeball it and drill a pocket with a forstner bit and then insert my drive center or my live center depending on which way I decide to mount it in the lathe. You can usually get pretty close.

Reactions: Agree 2


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## JR Custom Calls (Apr 13, 2015)

You can Put it between centers and adjust it until it doesn't keep rolling if you move it... Assuming it's fairly symmetrical

Reactions: Agree 1


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## Johnturner (Apr 14, 2015)

OK Dumb question - If it is mounted a little off center am I right in thinking that by turning a cylinder it becomes centered?


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## Schroedc (Apr 14, 2015)

Johnturner said:


> OK Dumb question - If it is mounted a little off center am I right in thinking that by turning a cylinder it becomes centered?



Yes, even if you start off a little off center when you round it up it'll be centered. One thing though to pay attention to with natural edge pieces is you can still end up off balance even when centered as one side might be longer/heavier that the other so just because it is vibrating it isn't necessarily off center.


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## Graybeard (Apr 15, 2015)

Saw a turner named Al Stirt - he used this in the drive center. http://www.alstirt.com/PDF files/BowlDriver.pdf By using this he can move the drive and tail stock as he goes to pick the best of the piece of wood. When he has it set up the way he wants it he cuts the tenon. This lets you adjust the wood until your satisfied with it. There are some commercially made drives like this but I can't find them. If your interested PM me and I'll look further.
Graybeard


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## Johnturner (Apr 15, 2015)

Interesting I'll try it.


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## Graybeard (Apr 16, 2015)

This is the commercial one: 



Graybeard


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## duncsuss (Apr 16, 2015)

I use "Stebb centers" (I think I have this and this from PennState). They work fine for me when dealing with irregular surfaces like burls.


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