pmpartain
Member
I wanted to experiment with eliminating or reducing runout when using a mandrel to turn both barrels of a pen at the same time. So, I have a Robert Sorby tailstock with interchangeable tips. The thing has a hole running all the way through it. Since I have been machining delrin lately I machined a tip for the tailstock out of delrin. Fits perfectly. While the piece was chucked in the lathe at work, I drilled the center hole for the pen mandrel using a D size drill bit. Another good fit and the hole is as centered as I can get it. The whole part was machined without loosening the chuck on the metal lathe.
Ok stuck the thing on the Nova lathe and got only a slight vibration on the bushings of a cigar pen. And I mean very slight. Basically I replaced the 60 degree live center with this thing that captures the end of the pen mandrel. You don't need any pressure from the tailstock to hold the mandrel. All in all I am pretty happy. Now I am wondering if I should try and stuff a 7mm turn inside the hole for durability. Will the pen mandred slipping around in the delrin wear it out quickly?
I had thought of doing this years ago, but saw a post about a similar tailstock sold by Penn State. Couldn't find it on their website though.
So this isn't my idea or anything, I am just trying it out. I'm not sure that it is any better than 60 degree point, and is most likely not as good as turning between centers, but it aint bad.
Ok stuck the thing on the Nova lathe and got only a slight vibration on the bushings of a cigar pen. And I mean very slight. Basically I replaced the 60 degree live center with this thing that captures the end of the pen mandrel. You don't need any pressure from the tailstock to hold the mandrel. All in all I am pretty happy. Now I am wondering if I should try and stuff a 7mm turn inside the hole for durability. Will the pen mandred slipping around in the delrin wear it out quickly?
I had thought of doing this years ago, but saw a post about a similar tailstock sold by Penn State. Couldn't find it on their website though.
So this isn't my idea or anything, I am just trying it out. I'm not sure that it is any better than 60 degree point, and is most likely not as good as turning between centers, but it aint bad.