CME 6" 4-Jaw Self-Centering (Scroll) Lathe Chuck with 1 1/2"-8 Threaded Backing Plate, Two-Piece Reversible Jaws

I'm so glad I bought this chuck! I was worried because the back-plate comes already machined to the chuck and I wouldn't be able to trim it down to match my machine to fix run-out. I was so happy after I installed it and measured it at the outer edge of the chuck and to find NO RUN-OUT! (none that I could measure). A steel rod clamped into the chuck and measured close to the chuck was the same. No measurable run-out with the indicator that I have. If the needle on the indicator is moving at all I can't see it. I couldn't believe it. I kept re-setting the indicator and trying again and again because it didn't make sense for it to be that good but every time it was the same result. No plate machining was needed at all. They did a great job on the tolerances with this chuck. That's is so much better than having to mill down the back plate like all the other chucks... (at least with this lathe). I was pretty disappointed with my lathe when I first got it when I saw all the wobble of parts that were clamped into the old chuck. (It's a 50+ year old Atlas 10F) I thought it was just because the lathe is so old but with this new chuck everything runs nice and straight and clamps tightly. What a difference this chuck has made to my lathe! I'm so happy with it and I didn't have to pay over $600 for it either.

I had to bore about .020", then removed .004" from locating shoulder and increased the depth by .025" out of the back plate to fit on my Jet 920N lathe but once I did ..it trued up to .0004" run out ... Looks to be a great chuck for a great price. I need to add an important update...please file and stone the jaws at upper chuck body They are razor sharp from rough machining.. Ask me how I know ? has been flawless since ....worth the $$$

Smooth scroll. looks to be durably made. When mounted on my old Delts Rockwell 10" Lathe, it was .005 off center. Jaws were parallel to the bed, but .005 is worse than what I was after. I did not need the hub on the backplate and there was no need for the extra stick out, so I turned that off. I flipped the backing plate around and turned the outer mounting lip to be true to the lathe bed. The cast iron does need to be polished a bit after turning, I used some 400 wet/dry paper. There is not enough step on the back of the jaw mount for set screws of any reasonable size so I took a truing cut on the ridge that centers the chuck. That gave me a few thousandths movement in order to bring the chuck center in line with the lathe spindle axis. I was able to get it to within .00085 and for the work that I do, that is good enough. I will test again after a few jobs and hopefully it will hold,

I'm very happy with this chuck on my Craftsman Commercial 12 lathe. The original three jaw had some runout in excess of .010. I screwed the backing plate on and mounted it on the lathe and had slightly over .001 runout. I'm sure with a little tweaking I could improve on that, but for my projects, that good enough.

This chuck and backing plate are ready to go right out of the box to an acceptable degree of accuracy. It’s 99%. The backing plate has a lot of material on it so it can be custom cut for greater accuracy without the hassle of starting from scratch. The thread engagement is very well cut and fits tightly. The back has enough material that if you have a step after your threads you can Bore out accordingly. I didn’t need that part and skimmed this part down for more thread engagement and less stick out. The face did have some runout which I skimmed true. Machining the front and back of backing plate on my lathe has ensured that this piece is running true on my machine. Upon assembly I have 0.0015 runout. This could be brought down to zero by cutting off the spigot and re machining one but I’m perfectly happy the way it is so didn’t bother with the extra effort. For something out of the box I think it’s quite incredible how close it is. For 10 - 30 minutes of effort on your part you can get it as zero as you desire. The jaws are ground well where they need to be. They clamp the work very sturdily. Reversible jaws on a small chuck is a game changer. It opens up a whole world of potential without investing in a whole new larger machine. I spoke with seller on the phone briefly, he was extremely helpful and nice. I’d highly recommend purchasing this product from this seller.

6" 3 jaw chuck, mounted the backing plate and threaded it on the spindle and chucked up a nice piece of brass roundstock and put an indicator on it, showed less than .0005" run out! (I didn't even face the backing plate yet as I wanted to be able to return it if I didn't like it ) I'll have to get out my interapid .0001" indicator and see what it actually is but one thing that's for sure is that this thing is a bargain! It cranks a bit on the tight side but it's smooth and consistent, I'm sure some grease will help with that.... I agonized back and forth between this and a Bison, the perfectionist in me really wanted the Bison but the realist in me wanted to try this first and maybe save some money for a Milling machine, I'm glad I tried it!

The backplate that comes with this chuck is perfect. Nearly 0 runout, but the chuck I received is not good. The jaws do not close correctly which adds .025” of runout on whatever is in the chuck. There isn’t enough play unbolting the jaws to correct this. Waiting on a response from the manufacturer currently

Improved my atlas 10” lathes accuracy by about 15 thousands over the old chuck I had on it fit perfectly very heavy and solid construction came with every thing I need to mount and assemble!