Grizzly G0602/G0752 Spindle replacement

So, the odyssey continues... I got the Bearings in put all gears etc back on. I was breaking the bearings in and I could hear slight clunking sound every once in a while. I took off the pulleys and all again then tapped in the left side bearing making sure it seemed all the way in and maybe a bit of preload on it. After putting it back together the noise had stopped so I assume the bearings just needed to be a little bit tighter. The spindle runout seems good, less than a half a thousands. I put a piece of 3/5 inch tool steel in the chuck and measured from one end to the other with my gauge on the carriage which showed me the head stock seems a bit off. Over about 8 inches it has a variance of about 4 thousands of an inch. So, it looks like im going to need to loosen the headstock and get that adjusted. sounds like it will be fun loosening the headstock to adjust. This was with my 3 jaw chuck so just to be sure, even though it will probably still be off, I am going to try the test with my 4 jaw chuck. After that gets adjusted I will need to adjust my tail stock too I presume. I will let you know how it all works out. Warren
 
I have a question, hopefully someone can help me. I am not sure the test bar I am using is perfectly straight. I used tool steel and center drilled it and the steel is supposed to be within .0005 accurate, but I it seems like it may not be exactly straight. Can anyone tell me a way I can test it to see? Or maybe I should just order one from ebay that should be good within 1 micron. They seem to come from india, has anyone gotton any of these and know they are accurate? Thanks for your input. Warren
 
Thank You Mitch, That is pretty much the way I am checking the spindle. It did give me a couple tips though. Actually my question though was about knowing if my test mandrel is straight or not. I think I am going to order one over Ebay to make sure. I want this as close as possible so there are no problems later when working with the lathe. Thanks, again. Warren
 
If you search for Rollie's Dad's Method and apply it you will find that a straight bar is not mandatory for success.
 
If you are talking about seating the bearing race, do not use the bearing it's self to seat the race by tightening. I'm not sure my perception of what your doing is right. If it is the race you can use a brass, or steel punch, and hammer, and tap in a cross ways manner. Hit one side cross over, and go around in a circle like that until you hear the race seat. there will be a change in the note when its seated solid. I think that is what your doing.....
 
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Aukai, Yes that is what I did for the race...Thank you. I was saying after it was all together I heard a little bearing noise when running the lathe. I tightened the pressure on the bearings a little and then the noise went away.
 
OK, I am wanting to adjust the headstock on the G0752. Was wondering , has anyone done this on the G0752/G0602 ? I was able to loosen the 2 bolts in the front under the control panel but in the back I can only get to one bolt without having to take out all the electronics, etc that is in the back above the motor. Is this the way I have to do it? , and If so do I just loosen those 4 bolts and tap the headstock until I get the spindle straight? , will it be able to move then or is it non adjustable? If non adjustable how would I get the spindle aligned with the ways? I know some lathes have an adjusting screw but this doesnt have that. Thanks for any answers. Warren
 
Well, since no one answered, (i assume no one has done this that read the question) my question about how to adjust the headstock on my G0752/G0602 lathe I emailed Grizzly about it so I thought I would quote them here for anyone that might wonder about it. Pretty simple procedure except for having to remove the electrical panel. Here is what they said in case someone is interested...

If the spindle taper has less than 0.0005” runout, install the test bar into the spindle taper. Now, with the test indicator attached to the cross slide, place the test indicator on the centerline of the workpiece at the front of the lathe, and test from headstock to tailstock to the end length of the test bar. Then, slightly loosen the fasteners holding the headstock in place and make your adjustments with light taps from a rubber dead blow mallet. Once you have reach the desired alignment, tighten the fasteners and retest the spindle alignment.

To access the headstock fasteners, you will need to remove the electrical panel from the machine. You will also need to remove the faceplate from the front of the lathe.
Thanks everyone.. Warren
 
Well, since no one answered,

One problem, is finding people who have your exact model, and who also have bothered to take the same time and effort as you in order to get accuracy to the state you have is going to be a bit rare :p

But thanks for confirming what they told you. On my King I've had to remove a lot more than just the electrical panel to get under all the bolts from the head-stock.

I did see an unorthodox method a while ago, where some Brit (I think) drilled two holes into the ways next to the head-stock, and put in bolts, then jerry-rigged them so he could put threaded pressure agains the head-stock. One bolt for left side, one bolt to right side. Then he adjusted the tension to get concentricity...

I'm not so sure that's a good way to go about it though. If it was, I imagine lathe manufacturers would/should come with pre-drilled holes into the ways, as they could then call this a FEATURE. Sorta like, how hardened ways is a FEATURE by some sellers.
 
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