Griz G0602 Runout

[purpleknif]

So last July I got a 10% off coupon from Grizzly and since I was looking for a bigger lathe I went ahead and got it even though I wasn't really ready for it. Needed to re-arrange the shop, sell my 7x10 etc.
My straight shank collet holder arrived yesterday and so I put it in the lathe to check it out. Hmmm,.006 TIR, Not good. So lets check the chuck. .006 TIR with a .500 dowel pin. So lets check the spindle. .0001" with my tenths reading Interapid. Nice lathe. So. stone the back of the chuck mount, Clean the mounting face on the spindle and put the chuck back on. .002 TIR to dowel pin. The chuck is mounted to an 1 1/2-8 adapter so I'm hoping I can loosen the cap screws an move it to true.
I might add that I haven't made a chip with it. Just now got it broke in according to the instructions.

 

[rodw]

So last July I got a 10% off coupon from Grizzly and since I was looking for a bigger lathe I went ahead and got it even though I wasn't really ready for it. Needed to re-arrange the shop, sell my 7x10 etc.
My straight shank collet holder arrived yesterday and so I put it in the lathe to check it out. Hmmm,.006 TIR, Not good. So lets check the chuck. .006 TIR with a .500 dowel pin. So lets check the spindle. .0001" with my tenths reading Interapid. Nice lathe. So. stone the back of the chuck mount, Clean the mounting face on the spindle and put the chuck back on. .002 TIR to dowel pin. The chuck is mounted to an 1 1/2-8 adapter so I'm hoping I can loosen the cap screws an move it to true.
I might add that I haven't made a chip with it. Just now got it broke in according to the instructions.

Sounds a bit like my lathe. Perfect alignment when measuring in the spindle but the 5C collet adapter through the spindle is no more accurate than my 3 jaw chuck. One day I will look at fitting a collet chuck. I have since changed the mounting of the collet adapter which needed a sleeve at the outboard end but have not checked if it is any better.

 

[hanermo]

Whats your goal ?
Most new lathes are ok on the spindle.

Not great, but ok.
About 0.008 mm, 8 microns, or a bit less than half a 0.001".

An adjusted collet system often will do spindle bearing error/0.000 if you have a perfect pin/fit/collet.
I polished a dc motor shaft extension to 6.000 mm +/-0 5 years ago.

The lathe has 2-4 microns tir error, but because it repeats, a turned object has near 0.