So far the clamps use has been discussed in terms of using it to clamp one part against
another, this of course being their main purpose but what about using one as a vice
or as an alternative to a vee block.
A toolmakers clamp will make a very useful instrument makers vice for working on
very small components as Photograph 9 clearly shows. Note that the special form of
clamp is preferable for this as both screws are on the same side.
If you required a length of 25mm wide bar but only have a length of 1" wide you
may wish to skim a little off to reduce it to 25mm, holding it on the machine table.
You will though need total access to the surface which may seem a problem. However,
using two clamps as shown in Photograph 10 makes the operation an easy one.
If you need to cross drill a part then the following using a toolmakers clamp is
worth considering. Clamp a piece of material between the clamp's jaws to ensure they
are parallel and clamp this to the drilling machine table. Let's put some dimensions
to the task to make the explanation easy to understand. Assuming that a 12mm diameter
part is to be cross drilled then space the clamps jaws as above using a piece of
10mm wide strip. With a short piece of 10mm diameter bar in the drill chuck lower
this between clamps jaws to centralise it, see Photograph 11, when fastening it to
the machine table. Not shown in the photograph but if packing of a suitable thickness
is placed between the piece of bar and the end of the clamp holding the assembly
to the drill table the eventual distance from the end of the workpiece can be set,
Start the hole using a centre drill following with a drill to the size. This process
would be particularly beneficial if a batch of identical parts is being made. As
illustrated, the process is only acceptable when drilling small holes. However, it
should not be too difficult to use an overhead workpiece clamp where larger sizes
Non Standard Clamps
Photograph 2 showed a design of toolmakers clamps that is far from common, however,
they do have some advantages. The clamps would be suitable for almost all applications
where the standard clamps are used but able to be of use in a few cases where the
standard ones would not. Probably the most likely usage will be on the drilling machine
table as Photograph 13 illustrates. In this a number of parts are clamped together
so that they can be drilled simultaneously. They can also be found useful when working
on the surface plate. The toolmakers clamp can easily be fastened to the machine
table using conventional overhead clamps where heavier duty tasks are being undertaken.
I consider that it would at least be worth equipping the workshop with the mid range
and largest sizes of this clamp, say 100mm and 150mm nominal lengths.
Whilst the design cannot incorporate a Tommy bar hole in the central nut, this is
of limited importance as final clamping is invariably carried out using the outer