Center of Gravity (CG) Test Rig

This rig is for finding and adjusting the camera and counterweights about the center of gravity of pipe or tubing which should be the center of the tubing/pipe (1). This makes adjusting the whole assembled system easier. Once the camera or counterweights are balanced they should remain in any position.

Note: This Arri 16S has slots (2) and screws for CG adjustments.

Note: The CG (1) is the center of the pipe and through the center of the camera. Dovetails (3) allow vertical and horizontal balance adjustment.

Note: These lead weights (4) are cast in 100" film cans with stubs of Speed Rail © 1-1/4" couplers (5). The CG is in the middle of the horizontal pipe.

This rig can be made with any 4 bearings or wheels (6). Cheap fixed casters would do. Attach the rig to a secure bench or base. Don't use a tripod unless it has a center post and can't tip over. When adjusting a camera consider a safety strap from above to catch the camera if something goes wrong. Provide stops so the camera can't slide out of the adjustable slots or dovetails. Make sure the lens can't slide out of the mount when the camera is looking down. It is easier to adjust the up and down axis with the camera looking up or down. There is no gravity to fight.

Make sure all adjustments are locked off after balancing.

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