         The Story of Springhooks
One of the most common tools used to repair adding and
calculating machines at Burroughs was the springhook. As the name implies, the springhook was used to manipulate
springs, which were very common in mechanical adding and calculating machines, during
assembly and repair activities. The
springhook was used for almost a century at Burroughs. While there were many types of springhooks developed, the
springhook of choice within the Burroughs service organization was really a set
of two, one called a pull hook and one called a push hook. Both of these springhooks were of solid steel construction, really just a
shaft of steel 11 ¼” long, which was ground to an inch long point at one end
with the tip of the point set at 90 degrees from the shaft and formed into a
hook. Each type of springhook had a
differently formed tip. The pull
hook was simply a 90-degree bend in the last 1/8th inch of the point
of the shaft. The push hook was more complex with a ¼ inch “S” shaped hook again at 90 degrees from the
shaft. The springs used in adding and calculating machines varied
greatly in size and tension. As time passed, the newer machines had more smaller springs. One common feature
of most springs was the “eyes” which were formed at the end of the spring by
the spring material being bent in a single loop at right angles in a manner that
allowed their connection to a post or a hole in the part to which the spring was
to be attached. Springhooks were
designed to push or pull on the spring eye in order to hold the spring and
direct the eye of the spring over a post or into the hole where it was to be
attached. The selection of the type of springhook used at Burroughs
was most likely done for four reasons. (1)
The length of the springhook was appropriate for the type of machine Burroughs
was manufacturing at the time. (2) The single-ended springhook was somewhat safer
to use than dual-ended hooks. (3) The solid construction was less expensive. (4)
The long slender tip and shaft of the springhook could be inserted into the
center of most springs allowing another method of manipulation and control. Springhooks were frequently used in combination with one
another as will be discussed a bit later. Every
Burroughs Field Engineer (FE) carried a number of both push and pull
springhooks. Some of the hooks were
modified for specific purposes by the FE, sometimes being selected for
modification when the original tip on the springhook had become damaged. Common modifications included grinding the end off to make a rather sharp
pointed tool for a variety of uses, most frequently as a probe of sorts. Another modification was to grind the tip down to a flat end somewhat
like a punch for driving pins. The
length of the springhook shaft again offered advantages over a typically short
punch. On occasion, a springhook
would have the end bend in a slight angle to manipulate a difficult-to-reach
spring. For a springhook to be of value it must be quite rigid and
“case hardening” was an important part of the successful manufacture of a
quality springhook. This allowed
heavy springs to be manipulated without the end of the springhook bending. There were, of course, limits on the tension of a spring that a springhook
could handle; but Burroughs also provided a very heavy version of the springhook
for these special needs. In using springhooks, there are a few cautions that need to
be explored first as follows. Always use eye
protection when using a springhook. Either end of the springhook can cause damage to the eye and it is
amazing how easy this can happen. Burroughs
Field Engineers were not specifically directed to use eye protection and many
injuries must have resulted over the years. Again, if are going to use a springhook, wear eye protection. Always ensure
that a motor-driven machine is completely disconnected from electricity when
springhooks are to be used. Because
springhooks are solid steel with no insulation, they can cause short circuits
and worse. Another reason to ensure
that electricity is removed from the machine is because, if you have a springhook
in the machine’s mechanism when the motor is energized (especially by
accident, hitting the “motor bar” on the keyboard), the springhook can be
propelled rapidly by moving parts in the machine. Now that you have been fairly warned about the hazards,
here are some tips and instructions for using these handy tools: Pull Hook – The pull hook is used to remove a spring from
a post or hole where it is attached. Insert
the end of the pull hook in the eye of the spring and pull it free from the
connection point. When the first
end of the spring is loose, the pull hook can sometimes be inserted into the
body of the spring to allow it to be pulled off the other end’s connection
while maintaining control of the spring. In a large Burroughs adder, the last thing an FE needed was
to drop the spring into the base of the machine (and you were lucky if it fell
all the way to the base). The pull
hook was also used to attach the first of the two ends of a spring to a post or
hole, again by inserting the pull hook through the body of the spring and moving
the spring into position on the first post or hole connection. At times, a push
hook was used with the FE’s other hand to guide the eye of the spring onto the
connection point. Push Hook – The push hook was most often used to push the
unconnected end of the spring by placing the saddle of the “S” shape against
the unconnected eye of the spring to a point where it could be pushed over or
onto the post or hole for attachment. One of the tricks of the trade was to use the push and pull
in combination to attach a spring in an especially difficult-to-reach location. This was done by placing the pull hook against a push hook with the tips
pointing in the same direction. The
pull hook’s tip would be down the shaft below the end of the push hook a bit
more than the length of the spring to be attached, from eye to eye. The two hooks were held tightly in the hand to eliminate the chance of
slipping out of this relative position while the spring was manually placed on
the hooks at the spring eyes. The
result is that the spring would be held firmly in place between the two hooks by
the tension of the springs and could now be positioned to the location within
the machine for connection. The end
of the spring further away from the hand (the push hook end) would be guided on
the post or hole and, when connected, the push hook would be withdrawn while the
pull hook controlling the unattached eye of the spring would now be used to pull
the eye to the connection point. This
combined use of the two types of springhooks was of tremendous value in placing
a spring in a hard-to-reach location. If you are going to apply these techniques, be sure to
follow the cautions outlined previously, and good luck. Like most things, a little practice makes all the difference in the
world. | 
