Unusual Tools: Padhacksaw, Hale, Hamilton & Co. Ltd,, London, England

This is without a doubt the strangest hacksaw in my collection.  Patented in Britain in 1939, it is very similar to the U.S. patent 2,724,417 awarded in 1955.

It's technically known as a "pad saw" intended for use in close quarters.  Typical pad saw designs in my collection are shown below:

One problem with these designs is that they leave the blade largely unsupported. By contrast, the Hale, Hamilton version uses a spring-loaded guide that moves backwards if an obstruction is encountered, and keeps the blade firmly supported near its cutting point:

Hale Hamilton was established as a defence contractor in 1947.  Today, the company is part of the Circor International Group and specializes in valves for navy ships and submarines.  The most recent naval submarine programmes using Hale Hamilton valves are the UK’s "Astute" class submarines, the Spanish S-80 submarines, and the German Type U212 and U214 submarines.