Gautam and Steve,
We have calibrated the load cells. The support beams height monitoring is almost ready.
The danger of this measurment that the beams height changes can put shear and torsional forces on this formed (thin walled) bellow
They are designed for mainly axial motion.
The plan is to limit height change to 0.020" max
0, center oplev at X arm locked
1, check that jack screws are carrying full loads and set height indicator dials to zero ( meaning: Stacis is bypassed )
2, raise beam height with aux leveling wedge by 0.010" on all 3 support point and than raise it an other 0.005"
3, replace levelling wedge with load cell that is centered and shimmed. Dennis Coyne pointed out that the Stacis foot has to be loaded at the center of the foot and formed bellow can shear at their limits.
4, lower the support beam by 0.005" ......now full load on the cells
Note: jack screw heights will not be adjusted or touched.......so the present condition will be recovered
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We could use similar load cells to make the actual weight measurement on the Stacis legs. This seems practical in our case.
I have had bad experience with pneumatic Barry isolators.
Our approximate max compression loads are 1500 lbs on 2 feet and 2500 lbs on the 3rd one.
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