Jims Mobile, Inc. (JMI) - RCF Base Plate

The Reverse Crayford Focuser (RCF) is a light-weight, low-profile focuser with a new revolutionary
design - JMI′s low-cost, high-quality answer to plastic focusers. The reverse Crayford
design gives zero image shift and zero backlash. (U.S. Patent No. 6,297,917)

All RCF focusers can be purchased with either a flat base or curved base (specify RCF model and
″flat″ or ″curved″ base).  The standard radius on a 1.25″ RCF
curved base is 3.75″ (7.5″ diameter). The 2″ RCF has a standard radius of
10″ (20″ diameter) and an optional radius of 5″ (10″ diameter).