Model Engineers’ Workshop – July 2019

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Secondary Hand Wheel

July 2019

found that it was possible to propel the
worktable faster and more comfortably
than before, without losing the ability to
make fine calibrated movements because
the primary hand wheel is independently
moveable, photo 4.
Making such an accessory is a very
simple project and the wheel can be
made from a variety of materials; hard
wood, metal, nylon and so on. The basic
objective form and profile is a matter of
personal choice. Something that feels
comfortable to use in the hand and which
rotates freely, are the main prerequisites
of the design. Obviously, the item must
be strong and durable enough to enable
rotation to be applied by prolonged
manual force.
For these reasons I chose to use a piece
of 50mm diameter, dense nylon bar 30
mm long, which I machined on a centre
lathe. After facing off both ends, a 12mm
hole was drilled through the centre for the
entire length, and one end was counter

bored to accept the head of an 8mm

socket headed machine screw. The nylon

form was then mounted upon a 12mm

threaded mandrel, tightly nutted down at

both ends, one end of which was secured

in the jaws of the three jaw chuck and

the other end supported by a rotating

centre in the tailstock, for the purpose

of machining a profile that was to be

approximately one half of the diameter of

the primary wheel that it would be fitted

to, photo 5.

Using a radius tool in the tool post, I

Something that feels

comfortable to use in the

hand and which rotates

freely, are the main

prerequisites of the design.

5 6

7

8 9

Bar ready for machining to profi le.

Machined profi le, almost complete.

Completed profi le, prior to fi tting of central

bush.

Brass bush. Counterbore with bush fi tted.