Abstract: A method of manufacturing box ladders having a pair of side rails and rungs wherein each of the side rails are assembled from a pair of section members having holes pre-formed prior to assembly of the side rail. The method provides reduced deformation in the manufacture of box ladders having cylindrical rungs and provides for the manufacture of box ladders having non-cylindrical shaped rungs.
Type:
Grant
Filed:
March 10, 1992
Date of Patent:
June 7, 1994
Assignee:
Featherlite Industries Ltd.
Inventors:
Michael S. Thompson, Frank Binder, Frederick A. Leech