related to the rear chuck & collet thread

[BHQ]

i mentioned in that thread that my spindle was not the same diameter throughout the length
that is true to an extent, but...............
i got to messing around with it today and discovered a worse problem
it's hard to see in this vid, but it's evident that it's also NOT ROUND
i chucked up a 30" purpleheart dowel, indicated on the back of spindle to within a 1000th or two , same at live center and at chuck
looked inside from back side of headstock and it's plain to see, that son of a ***** is out of round!!:angry:
no wonder my damn collets weren't always working out
it looks to me like the problem is right about in the middle of the spindle
the back and the front look ok




ADDED:
now , does that look round to you?

 

[Michael Webb]

option 1- if it's not hardened, have it bored.
option 2- Replace it or depending on the length of it, use the back chuck.

 

[BHQ]

option 1- if it's not hardened, have it bored.
option 2- Replace it or depending on the length of it, use the back chuck.

the only time this is , or was a problem, was with short pieces, say 12" or less
for quite sometime now, i went with another way
chucking up on the end of the piece and using a steady rest
so, i'm not going to worry about the spindle *option 3
i just didnt realize how bad it was until yesterday

 

[brianna187]

the only time this is , or was a problem, was with short pieces, say 12" or less
for quite sometime now, i went with another way
chucking up on the end of the piece and using a steady rest
so, i'm not going to worry about the spindle *option 3
i just didnt realize how bad it was until yesterday

with short pieces use a back chuck with a live center inside to hold work true they call this a whales penis mine is delrin about 16 inchs long with a live center inserted in the center press fit in then you can chuck up on delrin and adjust to where you need it

 

[BHQ]

with short pieces use a back chuck with a live center inside to hold work true they call this a whales penis mine is delrin about 16 inchs long with a live center inserted in the center press fit in then you can chuck up on delrin and adjust to where you need it

i didnt know the name of it,
but that is exactly what i was making yesterday when i saw this problem
as i said my spindle varies in diameter somewhat
when i turned the delrin, i was test fitting it from the front side/main chuck
i'll do it again, but this time, i'll make it fit at the rear 6" of the spindle that i know is good & true