Trying to Remember Things...

[StephenM]

Hi,

I was in a car accident in September and my parting gift was a couple of concussions (TBI). (All of the physical stuff has healed).

I can't remember things still and keep a list of stuff to remember and certain details are gone as well. My last IQ test was in high school at 136 and part of my NeuroPsych evaluation was an IQ test that came in at a scorching 85. Everything is still up there - I just can access it.

My wife's boss threw me a bone and ordered 75 magnetic Graduates (PSI). I was turning a sample and have a question -

I turned and sanded it down to the bushings and then I loosened the arbor screw and turned the blanks 45 degrees or so. There were a few high spots then that i sanded down to the bushings and now everything fits flush and when the pen is put together, everything fits fine.

Why does it do that? The bushings can't be out of round since it fits when it's put together and I remember that I always loosen and recheck but can't remember why. Or are the bushings out of round and there is enough "give" in the pen kit that you don't notice it?

 

[jttheclockman]

Sorry to hear about your situation. Hopefully things will return to normal.

To answer your question may be a mystery or it could be a couple things. The bushings could be out of round, or the tolerance in the bushing is not all that close. By that I mean when the tube is slid over the busing is it a tight fit or is there some play. Usually there is play not much but enough to make you notice if you are using the bushings as a guide to sand to. when you rotated the tube it shifted the tube on the bushing ever so slightly and now it is not sitting dead center. It was not before you moved it either being there is play.

Being you are sanding on a lathe things are round so it may be just a few mm off for fit on the kit you do not notice it. But that is where the calipers really do come into play. I do not sand with the bushings any more. I do not sand with my finger tips any more. I use a backer block on my sandpaper so that no odd pressure is placed in one area and not the others. Works for me. This is what I believe happened.

 

[rd_ab_penman]

TBC without bushings will solve your out of round issues.

Les

 

[larryc]

TBC without bushings will solve your out of round issues.

Les

Yes, but make sure you turn without bushings, because if you sand too much without bushings you'll get out of round. DAMHIKT

 

[magpens]

Sorry to hear about your TBI from the accident. . Hope things improve soon !

Turning Between Centers (TBC) may help, but it sounds like you have things pretty much under control. . It is a good thing to do that 45 degree turn followed by further sanding.

I have gone to TBC for all my pens now and I measure everything carefully with digital calipers ... it takes a little bit of time but I think it is well worth it.

I use a cone-shaped dead center in the headstock, and a live center in the tailstock and just mount my tubed blanks between the two. . You have to be extra careful near the ends of the blank so that your tool doesn't contact the cone or live center.