[Prev][Next][Index][Thread]
Re: More Tuning/Debugging
In a message dated 96-09-07 20:50:17 EDT, you write:
<<
> The stationary gap is suffering at this point. I built
>it with the gaps "close" to .028" each but now they vary from .014" to
>.041". I used 3" lengths of 1.5" O.D. copper couplings not tube. They
>have apparently stress relieved themselves with the heat and now have a
>changed shape. They were both bolted and epoxied into position in the
>PVC tube. I'm in the process of starting a new stationa gap system with
>a vacuum cleaner motor. More later, thanks for the feedback.
>
I find this interesting. I built my stationary gap with 1" Cu tube
sections bolted but not epoxied in place. It has always been
blown/cooled. I gap it to 0.030" and then, later, find that they have
moved;) Some are shorted, some as much as 0.060" apart. I figured that
this was due to not epoxying them in place. It has happened enough
times that I do not beleive it is stress relief any more.
jim
>>
Jim,
I built my cylindrical static gap with 1.5" dia copper pipe. I used brass
screws and nuts to hold them in place. Each pipe is also epoxied to the
large pvc pipe section they are mounted in. The gaps are set to about .030".
A muffin fan is mounted on the top with legs on the bottom to hold it about
2.0" up off the floor. The copper sections have been hot enough to turn the
surface blue - but no distortion yet. All the gaps seem to be holding as
originally set. I originally built two of these and one has several hours of
run time and still works great.
Ed Sonderman