No Bull Nose Center

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rake60

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The maintenance man at work brought me a hollow shaft out of one of the presses.
The shaft was about 5" in diameter and 12" long. It had a few scared up critical fits
on it that needed to be polished clean.
I had to come up with a way of chucking it up safely quick.

This isn't a new idea, I've used it many times in the past.
I cut a short length of 3/4" square stock and center drilled in in the mill.
With the shaft chucked up in the lathe, the square stock was used to stabilize the
outboard end.

This quick mock up in my hobby shop shows the general idea.

NoBellCenter.jpg


That is fine for polishing, but it is NOT stable enough for turning.

I have another time tested method for doing that.
I turn a fit on a small disk for a stuff to stuff fit to the ID of the shaft or tubing.
A press fit will be impossible to remove after the internal stresses relieve during machining.
A fit with too much clearance has other obvious drawbacks.
Then I flip the disk around, chuck on the fit that was just turned and center drill the disk.

Another quick mock up:

CenterButton.jpg


ButtonInCenter.jpg


That set up isn't going anywhere but around and around.
It isn't always a perfect center, but it's close enough for 99% of the things I do.

A better answer would be to buy a decent bull nose center, but how much fun could
that be? ;)

Rick
 

Maryak

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2 great tips, Thanks Rick :bow:

Seems so obvious when your shown how :)

For bigger pipes I have only ever used a spider.

Best Regards
Bob
 

rhitee93

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Maryak said:
Seems so obvious when your shown how :)

+1 on that. Thanks for sharing!
Now where is the forehead slap smiley when yo want one ...
 

Deanofid

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What a good tip. Some things are so obvious once I see them, I can't believe I didn't invent it myself. :big:
 

Philjoe5

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When turning pipe, I've found an end cap can do the job:

PA060005.jpg


Phil
 

rake60

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Philjoe5 said:
When turning pipe, I've found an end cap can do the job:

PA060005.jpg


Phil

Nice Phil!
I'll be adding that one to my mental archives. :bow:

Rick
 

rotorhead

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Whilst making a 50Int to 5MT adapter for my Dividing head, to utilise a homebrew ER50.

I machined the 5MT 1st then used the ER50 with a 1MT straight socket as the centre support.

DSCF0141.JPG


DSCF0143.JPG


DSCF0148.JPG


DSCF0154.JPG
 

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