Repair - Drill Press Vise

My Ryobi drill press came with a 2-1/2" vise. I'm generally happy with the drill press itself - it has given good service and seems reasonably well made for the price (although I have never dis-assembled it to really check). However, the vise that came with it (see at left) is another story. Although it worked, the action was always a bit rough.

I decided to take the vise apart to see if I could make improvements.

I never really looked at it to find out why, until recently, when it seemed to get even worse. First, a bit of background: The moveable jaw is clamped with a simple steel plate to the underside of the vise; the plate slides along two "runners" which are part of the base casting. I dis-assembled the vise and found two problems. First, the set screw holding the adjustment screw to the moveable jaw had a broken off dog point. Second, the "runners" were very rough - they had been only lightly ground (or perhaps never ground at all, and what looked like grinding was just wear).

The picture to the left shows the bottom of the vise (with clamping plate removed). It's a little hard to see in the picture, but the "runners" are just barely flat. The clamping plate was sliding on a very rough surface, and not making much contact with surface in any case.

Using a flat piece of steel bar, wrapped with 80 grit sandpaper, I lapped the runners to smooth out the bumps and provide more contact surface (see next picture). I considered lapping with finer grits, but the surface seemed smooth enough for practical purposes.

I also lapped the mating surface of the clamping plate. Notice that the lapping is only around the edges, as the plate has a slight bow in it. The bow may be intentional, in order to give the clamping a bit of "spring." In any case, it is only necessary to lap the part of the surface that contacts the runners.

At left is the re-assembled clamping plate. Notice the very rough edges on the non-mating ("upper" in the picture) surface of the clamping plate; it was simply stamped out, with no further finishing. A light film of lithium grease was placed on the mating surfaces.

Note that you can see part of the movable jaw adjustment screw on the right side of the picture. The screw is detached from the movable jaw in this picture. At the end of the screw you can see a groove; a dog point set screws fits in this groove to lock the screw into the movable jaw while allowing the screw to rotate.

The vise was then fully re-assembled. The original slotted set screw (holding the adjustment screw to the moveable jaw) was damaged - part of the dog point was sheared off, probably due to the previous "stickiness" of the moveable jaw. It was replaced with a hex socket set screw with a lathe turned dog point; lithium grease was again used on the groove (for the dog point) in the adjusting screw (you can see the groove in the photo above left). A bit of Loktite thread locker was used on the set screw to make sure it didn't work loose.

The repaired vise now works much more smoothly. Of course, it will never be a precision vise, but will still be a very useful tool so long as its limitations are kept in mind.