Harold Hall


Carry out preliminary machining, sides and bottom, for the area where the jaw keep plate will fit followed by the slot in which the jaw will slide. Despite the jaw having limited movement the slot runs the complete length of the casting. Centralising the slot on the drilled holes will ensure that it is adequately central, not easy to measure by other means. With the slot finished, return to the keep plate slide and finish mill both base and sides of the groove.


The Jaw

This is not an easy item to mount for machining due to its small size, irregular shape, and taper that runs from the working face back. Mount the angle plate onto the slide and onto this mount two supports for the jaw. These are positioned against the web on the bottom of the jaw that eventually will slide in the slot in the vice. The web is tapered as mentioned and the support pieces are angled to suit, Photograph 8. The jaw is then held in place using a bar clamp mounted from the angle plate and its working face machined.


Now with a flat face the jaw can be reversed and easily mounted directly onto the vertical slide using two bar clamps and the available surface machined. Place a piece of close fitting bar into the lower tee slot to act as added support for the jaw, thereby preventing the jaw from being pulled from the clamps holding it. This simple bar really is an essential piece of kit for the vertical slide and will see many uses, see  later Photographs 12 & 14.


Next, mount the jaw and machine the web, Photograph 9, making it a close fit in the slot in the body, but a little on the tall side. Note the rear support also being used in addition to the bar clamp.


Now, using a micrometer, measure the distance from the face on which the jaw is to slide to the face on which the keep plate is to slide. Add to this, say 0.002", and with a suitable piece of metal and a feeler gauge or two, or three, create a pack to this dimension. With the jaw still on the vertical slide, place the pack onto the sliding face of the jaw and using the saddle carefully bring it up to the cutting edges of the end mill and lock the saddle. Check that the pack will just move without play. At this setting machine the face on which the keep plate will be mounted. If you have slip gauges they would be even better. Do though aim to be on the high side, you will file a little off later.


Workshop Projects

Milling on the Lathe
Milling on the Lathe