question for those that turn pens between centers

Dan Noren

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ever since i started turning pen blanks, i have noticed two things. one being distortion on the inside of the bushings, where they are placed on the pointed centers, and the other being a black powdery stuff. i'm assuming that the powder is from the distorting of the bushings. i'm presuming that the bushings are a soft steel. has any of this happened to anyone else?

i've since picked up an adjustable mandrel, and will be using that.
 
ever since i started turning pen blanks, i have noticed two things. one being distortion on the inside of the bushings, where they are placed on the pointed centers,
Hi Dan; You're probably correct in your assumption below. (soft steel bushings) Turning between centres requires a bushing turned to much closer tolerances than what comes with the pen kit. I only use these bushings anymore.
http://penturnersproducts.com/index...Path=2&zenid=5f2b345c63e3cdaceed1cf82e5d6e76a I won't and don't use any other bushings than those made by this man.
the other being a black powdery stuff. i'm assuming that the powder is from the distorting of the bushings. i'm presuming that the bushings are a soft steel. has any of this happened to anyone else?
My opinion (which isn't always right) is that black powder comes from the bushings when you sand the pen blank. I only use delrin bushings when sanding now.
http://penturnersproducts.com/index.php?main_page=index&cPath=2_4
i've since picked up an adjustable mandrel, and will be using that.
The above bushings won't accept a mandrel.

The only occasion I use a mandrel now is in finishing my pens with CA.
http://penturnersproducts.com/index.php?main_page=index&cPath=2_15
 
This technique is new to me. Am I understanding that rather than using a mandrel, you place these bushings inside the ends of the pen tubes, then turn it between centers? What drive/tail center do you use? What are the advantages of this technique?
 
This technique is new to me. Am I understanding that rather than using a mandrel, you place these bushings inside the ends of the pen tubes, then turn it between centers? What drive/tail center do you use? What are the advantages of this technique?

There is an old thread around here some place with pics. When I get off my lazy horse, I'll find some pics for you.
But, yes, that is what you do. Also called 'no mandrel' turning. I turn almost down to the bushing, leaving just a few thou of wood above the bushing. Then I remove the bushings and generally sand, only rarely turn, those few thou off.
Advantages are there is no mandrel to flex and give you oval pen ends. It is far more accurate than using the mandrel. I do the 'no mandrel' technique with all my pens other than the 7mm ones. And those I use the 'professional' mandrel shortened and do only one half at a time to eliminate as much flex as possible.
The drive is a dead center on the head stock, tail is a 60 degree live center.
Do it once and you will never go back.
 
There is an old thread around here some place with pics. When I get off my lazy horse, I'll find some pics for you.
But, yes, that is what you do. Also called 'no mandrel' turning. I turn almost down to the bushing, leaving just a few thou of wood above the bushing. Then I remove the bushings and generally sand, only rarely turn, those few thou off.
Advantages are there is no mandrel to flex and give you oval pen ends. It is far more accurate than using the mandrel. I do the 'no mandrel' technique with all my pens other than the 7mm ones. And those I use the 'professional' mandrel shortened and do only one half at a time to eliminate as much flex as possible.
The drive is a dead center on the head stock, tail is a 60 degree live center.
Do it once and you will never go back.
What he said!
 
Thanks for the link the PenTurnersProducts site, Mack. I'd forgotten who made the "no mandrel" bushings. I think the next time I do a run of pens, I'm going to invest in the parts to do them that way. :thumb:
 
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