In August 2019, Clopay introduced a new commercial bottom bracket which uses a two piece design. Because the roller carrier is attached to the bracket with screws, it can be easily detached to replace the roller without removing the lift cable. This design also has an open bottom, which allows for easier replacement of the astragal and retainer. Because of these improvements, the springs do not need ot be unwound in order to replace bottom rollers, astragal or retainers.
See the attached Tech's Corner newsletter for additional information on the BB-2000 commercial bottom bracket.
Additional information on other types of bottom brackets is available here Bottom Brackets
Additional information on Low Headroom Bottom Brackets are explained in https://freshdesk.clopay.com/en/support/solutions/articles/67000713577-tech-s-corner-low-headroom-bottom-brackets-all-types
Reviewed: Sarah Cupp
Date: 12/16/22