Jerry, I would go with one inch dia. 0.049 wall
on this mount. The lower tube is susceptible to buckling
and you also have to worry about the long tube vibrating at
it natural resonant frequency. Dan can help us with that.

Paul Lamar

Dan Ruggirello wrote:

1"OD, .049" wall, 41.5" length, steel, simply supported

Lateral modes:
1st mode: 62.5 hz  (592 rpm)
2nd mode: 250 hz (2400 rpm)
3rd mode: 560 hz

Axial mode:
1st mode: 2450 Hz.

As long as it doesn't buckle it should be fine I would think.   It would be
most critical at low rpms exciting the first few lateral modes, but response
would not be very high because the tubes are mainly loaded axialy and not
laterally.  The higher frequencies (or rpms) are isolated by the barry
mounts.

Dan

Thanks Dan.

Paul Lamar
 
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