Plans used were those from "Bridge Jack Construction" by E.L.
Wolfensberger as published in the SCAVM Bulletin in November 1993 and
displayed on their website at
http://scavm.com/Bridgejk.htm. They are primarily for making one mainly
from wood, but being used to making things from metal I decided to make the
body from an off cut of 5/16" aluminium plate
(from Geraldton Boat Builders Pty Ltd.) The guides are from approx. 1/8"
nails, the screw 3/16" with Whitworth thread, and knob from 3/16" steel scrap to hand (only because I had no aluminium in that thickness.)
and a piece of leather from a worn out garden glove for the base.
The only tools required are a hacksaw, drill (preferably a drill press) flat and round files, sandpaper and a 3/16" tap.
In retrospect the screw length could be shortened and the knob made from thinner or lighter material, as the force needed to rotate the screw for lifting the strings is minimal.
This page was last updated on 07 April 2004