Why some lens cells of refractor / ED-APO / lens telescope cannot be adjusted

In some refractors/APOs, the spring ring is the problem. All three spring joints are bent inward. See photo.

This causes the lens assembly to tilt in the mount and can no longer be centered using the screws.
This problem often occurs with APOs from China. The Chinese manufacturers use cheap aluminum for the spring ring, which has little spring and also make the slots of the spring joints much too wide. If the lens is then subjected to a heavy impact from the front during shipping, the lenses compress and bend the spring joints, and the lens assembly is no longer firmly seated in the mount.

First aid:
The spring joints are bent back into place and the screw ring is tightened slightly so that the lenses have no play and cannot hit the spring joints.

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