off center turned blanks

nonimac · 11-30-2011, 03:05 PM

Hello,

I have only been turning pens for about a year now. Recently I have noticed that the last few blanks I turned have been off center. Meaning thin on one area and thick in another. I am wondering what could be the cause of this. I have a strait mandrel. If anyone could offer any insight I would appreciate it.

D.Oliver · 11-30-2011, 03:15 PM

Is it possible your are tighting the nut down too tight and causing the mandrel to flex?

butchf18a · 11-30-2011, 03:34 PM

If you are certain your mandrel is not bent; Derek is right about tightening the nut excessively. There is another possibility; when you set and then tighten your tailstock, it is easy to over-tighten and bend the mandrel. When you loosen the tailstock to remove the pen, the mandrel will return (material memory) back to straight.

nonimac · 11-30-2011, 03:44 PM

It is very possible. I have never thought about that, I am going to loosen it up and see if I can true it up. thanks for the replies.

11-30-2011, 03:05 PM	#1 (permalink)
nonimac Join Date: Mar 2011 Location: Lodi, Ca Posts: 8 Photos: 0	off center turned blanks Hello, I have only been turning pens for about a year now. Recently I have noticed that the last few blanks I turned have been off center. Meaning thin on one area and thick in another. I am wondering what could be the cause of this. I have a strait mandrel. If anyone could offer any insight I would appreciate it.

11-30-2011, 03:15 PM	#2 (permalink)
D.Oliver Join Date: May 2011 Location: Faith SD Posts: 1,498 Photos: 9	Is it possible your are tighting the nut down too tight and causing the mandrel to flex? __________________ Derek Oliver Penturning - Its basically taxidermy for trees.

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11-30-2011, 03:34 PM	#3 (permalink)
butchf18a Join Date: Dec 2010 Location: woodland, wa Posts: 291 Photos: 6	If you are certain your mandrel is not bent; Derek is right about tightening the nut excessively. There is another possibility; when you set and then tighten your tailstock, it is easy to over-tighten and bend the mandrel. When you loosen the tailstock to remove the pen, the mandrel will return (material memory) back to straight.

11-30-2011, 03:44 PM	#4 (permalink)
nonimac Join Date: Mar 2011 Location: Lodi, Ca Posts: 8 Photos: 0	It is very possible. I have never thought about that, I am going to loosen it up and see if I can true it up. thanks for the replies.

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