CME 8" 4-Jaw Scroll Lathe Chuck with 1-1/2"-8 Threaded Backing Plate

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.

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!

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.

Back plate with 1-1/2-8tpi.was not running true.mine was running about 5 thou. of run-out.and being the register was a tight fit on the chuck body the runout transfered to the chuck.i turned a couple of thou.off the register and that gave me some wiggle room to bump the chuck true.now it's running about 6 tenths. The chuck it's self,was pleasing to the eye.everything was nicely ground.disasembled the chuck to inspect and clean the scroll plate and pinion gears and was surprised that I didn't find any grinding residue or burrs on every piece.the jaws and chuck body were numbered as well as the reversible jaws.however the jaws did have some burrs on the flats between the threads.it looked liked the tool that was used to machine the threads was damaged and mangled the flats.i used a dremmel to smooth out the damage and all is well.if the jaws didn't have the damage I would have given 5 stars.over all, it's still a quality chuck and I would recommend it.

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.

Fit my lathe like they said it would

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

Beefy chuck, runout was only around 2-3 thousandths, honestly super impressed. Put it on my 1930s atlas lathe.