few questions

One thing that should said is to NOT adjust the load on the bearings when the machine is cold. As the machine warms up the bearings will be too loose, but again you really have to be careful if setting up the bearings when hot. They will too tight at startup. You want to adjust them after running the lathe for 20 minutes or so, not cold, not hot, just warm. After that you will have to run the lathe more to see how things go when it gets fully warmed up. You may have to back off a bit, if the bearings are too hot, or the opposite if the spindle gets too loose.
Check for runout and readjust to reduce to minimum without over heating the bearings.

Pierre
 
You can do it that way but if you do, you should only tighten the collar to a snug zero clearance when warm. And disregard the instruction to tighten 1/16th of a turn or 2 teeth on the gear. Reading between the lines, someone at Atlas 70+ years ago must have spent some time determining average spindle and bearing warmup during operation and calculated that the collar rotation to compensate was equal to about two teeth on the 32T spindle gear. Because in the factory instructions, it only tells you that after pre-loading cold, the spindle will lengthen about 0.002" when warmed up.

Also, there is a typo in the Bulletin. Instead of '1/16th turn' it says '1/16" turn'.

Robert D.
 
thanks for the info. now i need to get another chuck for it what size are the threads for the chuck?
 
Spindle nose threads on a 12" are 1-1/2"-8.

Robert D.
 
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