If you already have a four jaw chuck then facing the ends whilst in this will be
the easiest method to adopt, if not, then doing this on the milling machine is the
only option. Photograph 12 shows my method of machining the four at the same time
using my engineers sash clamps but machining one at a time in a conventional vice
would be an acceptable method.
Whilst there is no essential order for carrying out the remainder of the machining
operations I think that making the 10mm web along the base of the jaw is a good starting
point. I say 10mm but there is a possibility that the slot drill if not running perfectly
true will have cut a slot slightly oversize so measure the slot before machining
the web. However, this is not a moving jaw like those in a four jaw chuck so a very
close fit is not a requirement. Photograph 13 shows my method of carrying out the
machining having one fence to set the height and one to assist with opposing the
cutting action, one clamp is therefore more than adequate. Still with this set-up,
also mill the 1mm deep recess the purpose of which is to permit the jaws if required
to be compressed by a small amount when holding larger rectangular items.
Drill, tap and counter bore the holes leaving just the jaw to be slit and if you
have a large slitting saw then do this on the milling machine. Photograph 14 shows
my method , the angle plate is just giving some added support to oppose the machining
force though this was probably unnecessary but it does serve a purpose with the next
part so arrange to machine the slots in both whilst this set-up in on the table.
Whilst not seen, a similar thickness piece of steel was placed between the jaws at
the other end as holding a component at the end of the jaw without this being done
is definitely taboo, even with a quality vice.
If you do not have a suitable slitting saw then it is a task for the band saw and
failing that a manual operation with hack saw. Whilst neither of these methods will
be visually as elegant they will function equally as well.
Thin Piece Larger Diameter Clamp (6)
This is a straight forward part but have included a shot of my method of facing the
ends. In this, Photograph 15, the lower member packs the part up to keep the cutter
clear of the table's surface and a fence is clamped on top enabling the parts to
be positioned so as to machine their ends square. The head of the screw that secures
the two parts to the table also acts as packing for the clamp that holds the workpiece.
The fence in front sets the position of the workpiece enabling a consistent length
to be achieved with ease on the second end. This method was much easier than fiddling
around within a vice's jaws particularly when making a number of identical parts.