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Kurt Milling Machine Vise Rebuild

A while back I picked up an older Kurt D60 vise complete with no jaws and 40 pounds of swarf on C-List for $95. It was in pretty fair shape, with only one really substantial divot, but it was stiff and grungy. I tossed it on my workbench, and used it to grab stuff for a while until I sold my offshore mill vise to John Leatherman at the CAMS Yardsale. There was nothing wrong with the Chi-Vise, but the Kurts just work so much better. A month or so later, I found a decent Kurt swivel base on Ebay for about fifty bucks. All I needed was a set of jaws, and some T-bolts to get started. I ordered a rebuild kit and some table keys while I was at it. The total expenditure for the vise, swivel base and parts was about $225.
The entire “rebuild” took about 5 or 6 hours, mainly due to taking pics, and the fact that I had never taken this type of vise apart before. After having done it once, I could probably get the job done in a couple, maybe three hours. I wasn’t going for a “Pebble Beach” restoration, I just wanted to get a functional vise back on my mill, and figgered I’d throw a little money at it to make it a little better. I could have skipped the overhaul kit, as the existing parts were all good, but the kit cost $10, so why not? The finished product looks just marginally better, but functions smooth as silk. I’m glad I spent the time to get it apart for a good cleaning.
The total tools used were 3 or 4 Allen wrenches, and some wet stones of various grits. The vise was given a real good cleaning in my parts cleaner before I started the dissassembly. Heres what I started with………mvc-090f

And heres the parts…………..mvc-092f

Dissassembly, starting with removing the allen bolts from the fixed (rear) jaw…………..mvc-093f
Then removing the movable jaw. This requires removing the lock ring off of the main screw, then just backing the screw out.mvc-094f
Here we are 5 minutes into the job.mvc-095f
Heres a couple of shots of the locking mechanism on the movable jaw. The half-ball rides on an angled ramp that pulls the movable jaw down when tightening. This small detail is what sets Kurt vises apart from their Chinee clones. Here you get a good idea of just how much crap accumulates in the hidden recesses of your vise.mvc-096f
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The first step was to flat file with a very fine toothed mill file to get all the dings and divot off. Five minutes work took all the high spots off so it would sit flat and mate together nicely. No major surgery here.

***UPDATE 8-4-2013***

I’ve had quite a few Emails chastising me for raping my vise by dragging a wood rasp across it. To be clear: this is a VERY fine 2 inch wide mill file with very sharp, very shallow teeth, designed for removing high spots on precision surfaces. While alot of time was spent drawing the file across the vise, the only thing removed was high spots and burrs. Once they are gone, the file just glides across the surface.

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Next, getting the burrs off the fixed jaw with the fine file, then a stone.mvc-104f
Then the base gets the same treatment.mvc-105f
Heres a shot about 1/2 way through stoning the ways on the base of the vise. There is a couple of pits in the way due to coolant erosion, so its never gonna be perfect. The ways are smooth with no high spots, and I’m happy with them.
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Stoning the movable jaw is next.
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Chasing all the threads………….
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Heres everything cleaned, smooth, and ready to go together.
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Heres a couple of shots of the screw, and the new torrington bearings included in the kit, and as installed (shim-bearing-shim).
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Reinstalling the locking collar with a couple of thousanths clearance.
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And the base of the movable jaw.
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to reinstall the top part of the movable jaw, first grease the 1/2 ball in the tapered part of the locking tang.
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Then place vise jaw like this….
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Then tip the jaw towards the front, and pull towards the front at the same time. This will join the two locking tangs.
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Then install the allen set screw to keep the two parts of the jaw together. You will need to leave about an 1/8 of an inch of play (maybe back the screw out one turn), other wise the slide will bind. The ball acts as a fulcrum to lock the jaw to the way, and that is the way its designed to work. Just leave a little play in the screw, so you can assemble the vise, and play with the adjustment later.
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Install the fixed jaw.
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Then the cap that keeps chips out of the screw.
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Now you can install the new jaws. First the fixed jaw.

***UPDATE 8-4-2013***

I’ve been told that the Kurt manual tells the rebuilder to put the vise in a press to preload the jaw against the way before torqueing the jaws down. Presumably, this is to register the jaw tight to the way for accuracy and repeatability. This makes perfect sense to me, but as I didn’t have this info when this article was written, I just held it down with hand pressure when I tightened the jaw. Additionally, I didn’t torque the jaws, merely locked them down tight.
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Then the movable jaw. I put a sheet of paper under this (sliding) jaw to keep it off the ways.
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There Ya go, now onto the base.
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First, install the keys. This will keep the base pefectly indexed to the table on your machine.
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Then install the T-bolts for the vise.
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Then apply a little way oil to the sliding surfaces before dropping the vise on. Be sure to use a wood block, so you don’t damage the new table keys.
Way Oil in our store..
Set your angle to zero degrees.
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And tighten her down.
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Here it is temporarily mounted to the mill, using the T-bolts from the Chinee vice. The old bolts are too short, because this base is thicker, and I will change them shortly. I haven’t trammed it yet, but just threw an indicator on it real quick, and it looks to be real close right outta the box. I’m happy. All that is left is to fit new bolts, and make some chips!
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I did not intend to restore this vise to Concours condition, I just wanted to make it right, with a minimal expenditure of time and money. For about $225 total cash outlay (that includes the price of the vise), and an afternoon and a half of labor, I’m happy with the results. The vise has a much stiffer feel than the old one, and grabs my work much tighter. The jaw contacts the work, and locks tight within 1/8 turn, and feels like a bank vault. I can’t help but feel that it will improve the quality of the work going out of the shop. I can hope, anyway………………

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