Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

I don't see anything wrong with your methods there Jim, but I'm not sure of the merit in checking the runout of the outside diameter of your chuck, other than it really should be fairly close to concentric so as not to cause a balance problem when spinning. Certainly the workpiece should be perfectly centered in the jaws, but that needs to be checked with a nicely prefinished stock piece like a dowel pin, ejector rod or pin gage if you have a spare one you don't mind chucking up, and not with a workpiece that you just turned. Any piece you just turned should show no runout if it hasn't been removed from the jaws yet, but is it concentric or co-axial with the part that is being held in the jaws? The inside of your spindle needs to be true so any collets or other tooling that it may be tapered for run true, and that should be a fair test of your lathes spindle and bearings as well.

While you are at it, try lifting, pushing down as well as in and out on the spindle nose and see if there is any noticeable deflection there, and if so you may need to tighten your bearings slightly.

It's late, and I'm sure my explanations could be much better, but I hope you get the general drift of my meanings.

In my opinion the first one (checking spindle ) is ok
 The other two are a waste of time