Thursday, January 6, 2011

Wheel Surgery


"Doc, it chatters when I do this....

...Sometimes it even flies off the wheelhead and onto my lap -- at full speed! . Doc, I need speed. I can't work like this."

"Well, I could write you a prescription to just be very, very careful and make sure you don't pull the clay up too fast, but that defeats the purpose. It would add countless hours to your production time over the course of a year. I think it's time we consider surgery."

"You mean...?"

"Yes. I think it's time we considered replacing your old, worn out bat pins."

Every few years I have to replace the bat pins in my old Pacifica Glyde Torcs. They'll go for quite a while holding my bats well -- even years. But as soon as a gap begins to develop such that the plastic bats can chatter against the pins, in a relatively shorter time that chattering beats and abrades those pins down to nothing. Before I know it, they barely hold.

But the wheelhead is getting mighty old. That aluminum is oxidized and it's getting harder and harder to get the pins out. Last night I found that I didn't have a tool with which to do it. No plyers, wrenches, torches, lubricants......nothing was going to loosen those pins.

I finally decided that I had to take the risk and drill them out -- "risk" because I knew that the chance was very great that trying to drill the hard stainless pin out of the softer aluminum wheelhead would result in the spinning drill bit drifting into the path of least resistance -- the aluminum.

But I did it. I drilled clear through the pin without damaging the surrounding aluminum.

But it STILL didn't remove the pins. Now I had holes through the wheelhead, but the shell -- the threads of the residual bat pins -- remained stubbornly in place. And now there was no bolt head with which to try to pull them out.

I went to bed with them stuck that way.

First thing this morning I went over the John White's machine shop. One of the benefits of living in an industrial park -- White's Machine Shop is my neighbor.

John had a drawer full of those backwards-threaded screw extractors. After trying several, we finally found one the right size and with sufficient bite to grab one of the residual pins and cause it to thread the rest of the way out the bottom. The other we had to swallow hard and just drill the rest of the way. Even the larger bit left some of the stainless threads embedded in the aluminum. But when John re-tapped the holes, those threads finally exited out the bottom.


I fabricated new pins when I got back to the shop. I have about 85 bats -- half plexiglass (pictured above) and half that are plastic. Not only is my Glyde Torc set up with bat pins at the now-not-standard, eight inch centers, but there is no standard cap head screw that fits them.

The way I fashion the new pins is to chuck them up in my drill (with the threads in the chuck). and spin the head against the spinning grinder. It doesn't take too long to grind them down to the proper circumference. I just keep water nearby. I grind for a moment, dip the now hot pin in water for a second so I don't melt the plastic when I try it out for size in a bat hole.

4 comments:

  1. Remember, with any cosmetic plastic surgery there can always be risks and complications that can occur related to infection or a reaction to anesthesia. But with precautions by the surgical team, complications are typically minimized or prevented. Make sure you ask all the right questions as to what to expect before and after your surgery.

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  2. The operation was a success. Nuthin' cosmetic about it, Jazzie. That poor wheel is a old, ugly workhorse. But we'll watch out for complications. I even re-tightened the pins this morning. I don't want a relapse.

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