More On The Modified Drill Press Vise

More On The Modified Drill Press Vise

I used to make a ScopeRoller set for the Vixen HAL-110 tripod. Or more accurately, I made one, because it was a challenge--and since then, I have turned away a second order for it, and for the very similar HAL-130. Why? Because I couldn't hold the workpiece solidly enough in the Sherline mill vise to machine the part.

The modified drill press vise seems to be doing the job adequately. I can take much deeper cuts, because it holds the workpiece much more solidly, and because it is big enough for me to lay the workpiece (which is 2.62" wide) down flat for milling. In addition, the drill press vise is big enough that I will be able (I think) be able to put three workpieces in at once, and use a fly cutter to do some of the operations all at once. (I might have to bolt all three of them together, however, to make sure that they don't slip on the Delrin to Delrin surfaces. Not a problem. I drill a hole anyway to speed up milling a slot, so I can use that hole for the bolt.)

I also had a chance to do some more accuracy checks. In the Y-direction, accuracy is excellent. I squared my workpiece, and it was square within the limits of my measuring device (<.001"). In the Z-direction, it isn't quite as good; within .015". Part of the problem may be that the movable vise jaw has some play in it (of course), and so if the workpiece is off-center between the jaws, it tends to pivot the workpiece slightly.

I put a piece of Delrin of almost the same width in the vise at the same time, to reduce the pivot; it seems to have knocked it down to perhaps .008". That's good enough for the rough cuts for which I am using it. It is probably good enough to ship to customers; but if I decide to be more careful, I can rough cut to 1.40", and then remove the last .010" with the workpiece sitting vertically.