Seismometer Pivot

Pivot end of rod

pivot end of rod for horizontal seismometer

The horizontal rod extends to the right and is sharpened to a blade
where it contacts the frame, which is made of steel pipe.

I found that putting a bolt on the rod near the bladed end was helpful for those times when the rod was to be moved or maintenance was to be performed.  Otherwise the bolt is simply moved out of the way, which is the situation that is shown above.