Harold Hall
An essential operation when milling is to lock the two slides that are not being traversed during machining and is especially so when milling on the lathe due to the light nature of the set up. Unfortunately, the position of the vice on the vertical slide prevented access to the locking screws, the top and bottom gib strip screws had therefore to be used, not idea, but essential. Next fit clamps on the slide ways, just machined, and then remove the clamps initially fitted. This enabling both edges of the base to be machined.
The next stage is to machine the surfaces on which the jaw slides. This is an example of the problem of a limited size worktable. With a normal vertical mill the vice could be stood on the table and held in place by a bar clamp at either end. the two surfaces then be available for machining at the one go. This cannot be achieved on the limited size of the vertical slide.
Place a piece of bar into the lower tee slot, as mentioned earlier, and rest the vice on this to take the weight whist placing clamps to hold it in place as shown in Photograph 4. This set up must be done with care to ensure that both sides of the vice's base are firmly in contact with the vertical slide face. For this to be achieved, the packing under the bar clamp must be a little higher than the vice portion being clamped so that the clamping pressure is applied only at the clamps end. The clamp must also be long enough so that pressure is applied close to the inner edge of the upper jaw slide surface.
Take a very light cut over the lower surface, setting a saddle stop to this position
so that the other side can be machined at the same height. Having machined the one
face, remove, turn over, re-
Do take the absolute minimum off as this operation lowers the jaw and therefore the position of the hole in the moving jaw, miss aligning it with the tapped hole for the feed screw. However, the screw in the tapped hole and the end in the moving jaw had generous clearances so there was not a problem.
Mount the vice body on packing on the cross slide and mill the groves along the length of the body on either side, Photograph 5. Make these 8 mm wide, 6 mm from the base of the vice to the edge of the grove and 5 millimetre deep. However, the height of the groove above the base is not critical as the clamps can be made to suit. There is therefore some leeway on the height of the packing used.
Metalworking
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