Make rotation clamps from two pipe clamps for Newton:

Product Description
Making rotation clamps from two Newtonian tube clamps:

A Newtonian telescope needs to be rotated from time to time to achieve a comfortable viewing position. On an equatorial mount, the tube, and thus the focuser, rotates with the Earth's rotation.

When rotating the tube, however, it will often slide downward, shifting the center of gravity and moving backward. Special rotation clamps are available, but they are quite expensive.

In this case, you can use an additional tube clamp, which is clamped directly under one of the existing tube clamps. Since screws often protrude here, you first have to replace the screws with countersunk screws. To do this, remove the protruding screws and use a countersink to enlarge the holes so that the countersunk screws can also be countersunk.

A layer of Teflon can be placed between the tube and the two tube clamps to make rotation easier. The additional tube clamp holds the tube in position.

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