Improving the apparatus stiffness

Now that the cryo-friction rig is finished, we are running through a litany of calibrations and tests using standard materials. During this process we realized that the stiffness of the rig needed improvement. Our 1" thick aluminum top plate was deflecting a small amount with large load. Even though that load is probably bigger than our usual load will be, we still want a very stiff apparatus for friction experiments. So we have added a 3/4" steel plate to the top, between the plate and the piston.

We bought some pieces to act as spacers and square washers to clamp down on the plate using the existing nuts and tie rods.

But the pieces that we ordered weren't the right size, nor even uniform in size. So we had to cut and then sand them all down. New undergraduate intern, Channing, helped with this process. First he carefully sanded each one on the belt sander, measuring after each sand.

And then he installed the pieces and washers to the rig. I can't wait to see the improved stiffness measurements!