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Robert LaLonde
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That is pretty normal for an inexpensive 3 jaw in general HF or otherwise. pull the chuck and indicate the inside the spindle bore. I bet its around .0005 - .001. My 8.5x18 barely moves the needle on my Last Word indicator. I use it for small stuff so I set it up with a 3C adapter and a 3C closer. Its under .001 all day long. If that's not good enough make an adator plate for a 4 jaw or for a pull back chuck.I picked up a used 8 x 12 Central Machinery lathe.
Tag says 07 model ...
Guy i bought it from said he only made watch or clock parts or something ......
machine is not wore....
it's not scratched or dinged up it just look like it's been sitting in a basement for a long time paint looks like it's new.
Most of the tools are still in the plastic so fella didnt do much with the lil thing....
This is my first mini lathe...
I've been Machining for 20 years....
So the machining aspect is not my issue...
I've got the lathe setup on the table that I made and I'm now going over it with my ol trusty interapid test indicator.....
I put a dowel in the 3 jaw Chuck and I can get about .003 run out which I understand or am I'm hearing this is typical , normal or in tolerance...
I need it better !!!!
Could be the boss for the chuck was not cut in place. It could also be the chuck is off that much. Might also check it with different size gage pins just to see. Not only do inexpensive scroll chucks tend to be off they tend to be off by different amounts at different diameters. Again, go with a collet adapter, collet chuck, or 4 jaw if you want better.so I took the chuck apart today deburred ,cleaned it up, took a stone to it and just made it slick as could be.....
reinstalled and I'm still .oo3 out of round
That may be easier to fix. The head stock is just bolted to the bed , and the bottom is pretty rough. Could jus tbe a burr or chip in there. If not its dead easy to shim.not to mention out about the same horizontal in 4inches or so toward chuck.
Well that pretty much confirms it. Its just a cheap 3 jaw scroll chuck then. .005 isn't uncommon. .003 is pretty good.I guess the confusing part is when the chuck was off I put the test indicator on the adapter and swung it and I can't get a half thousandth of variance anywhere....
I don't think so. You might be able to feel .003 slop in a spindle by shaking it. They are just a grease lubed bearing though. Unless its different from the 7x10.Bearings maybe ?
I've been reading post after post after post and videos on YouTube and all kinds of stuff on this lathe and I figured I would start my own post to get some insight I plan on doing quite a bit of threading with the lathe as soon as I can figure out how to engage the half nut and change the change gears I'm use to a big mazak I don't think I've ever changed, change gears before ?
Any input would be greatly appreciated
Thank you
You are so going to miss your QC Gear Box. LOL. The half nut and engages the drive screw for both threading and turning. It does not have its own threading drive like bigger lathes often do. You are going to be swapping gears all the time. I suggest that one of the first things you make for it are long shoulder bolts with knurled thumb heads to make taking the cover off to change gears easier and faster. To go from turning to threading... yep. Change gears. MANUALLY.
The next thing I suspect you will miss is having a power cross feed.
Probably one of the first things you should do to the carriage is build a set shims so you can tighten the screws down tight on the sandwich plates and have very little movement. Just enough so it still slides easily.
I have a 7x10 converted to 7x16. Very similar machine.