A new longer keep plate could easily be made and fitted, which together with the
improved machined face would considerably reduce the problem. Having decided that
it would be possible to resolve this problem, generally improving the overall accuracy
should be quite possible.
Having said that achieving a more accurate vice is possible, does not mean that it
is straight forward. The major problem stems from the fact that it is a tilting vice.
As a result, many of the machining operations have to be carried out with reference
to the hinge pin.It would be easy to arrive at an adequate result in the horizontal
position. Then only to find that the vice jaw is not parallel to the base when pivoted
through ninety degrees, due to the appropriate procedures not being adopted.
The requirement for improving the vice also assumes that it may at some time be used
without the base. In this case therefore, the lower face of the vice must be machined
to achieve accuracy when used in this manner.
For the newcomer to milling, improving this type of vice will be a challenging project,
and one from which much can be learned. For that reason the procedures are given
step by step, both in the text and in the illustrations.
It is probable that the underneath face of the base will be satisfactory. This can
be determined by placing the complete vice on a surface plate, to determine if it
rocks. The test can also be improved by testing with the thinnest feeler gauge available
around the base. If a surface plate is not available, the milling machine table could
be used as a substitute. Slight errors could be eliminated by the use of marking
blue and scrapping the base.
In the unlikely event of a large error being present, the underneath will require
lightly machining. This can be done by turning the vice upside down and clamping
it, using its own jaws,onto an angle plate fixed to the milling machine table. Support
the handle end of the vice using a makeshift jack(typically, screw into a tee nut)
if you do not have a proper one.
With the vice set up, lightly machine the faces to arrive at a satisfactory result.
This operation is not shown in the Photographs, but all the remaining major stages
are illustrated. It should be added at this stage, that in fact the Photographs were
taken after all the machining operations had been completed. The reason being that
originally there had been no intention to make an article from this project.