one small nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming

a slot is cut partly in middle of nut and then slot reduced by tightening a screw

hard fiber or nylon cotter is recessed in the nut and becomes threaded as the nut is stewed on the bolt causing a tight grip

through slots are made at top and a cotter-pin is passed through these and a hole in the bolt, and cotter pin splitted and bent in reverse direction at other end

102 d

124 d

138 d

168 d

right hand with same pitch

left hand with same pitch

could be left or right hand

right hand with fine pitch

1 in 5

1 in 10

1 in 24

1 in 40

metric

buttress

acme

square