What is acceptable runout?

Bill Lantry

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Hey, folks,

Just got the lathe up on its stand and turned it on. I know next to nothing about lathes, so this may seem like a stupid question. Anyway, here's the story: The box came last week. I wasn't home, but Doorlink was. She took delivery, even though the box was pretty messed up. Now that I've taken a pretty good look at it, it seems the headstock is out of alignment. Or rather, the motor itself is not exactly parallel to the bed. Almost, but not quite. Don't know if it's supposed to be like that or not.

But the real question: I put the delivered faceplate on the spindle, and turned it on. I haven't measured, but I can see visible runout. That is, the edges of the faceplate blur as it's turning. Noticed the same thing, less pronounced, with the spur center on it. Should I be seeing this much, or should I call the manufacturer and get them to send at least a new headstock?

All opinions appreciated!

Thanks,

Bill
 
If you can see runout, it's to much.

To get an idea of how bad it is. Clamp something like a board to the bed with a nail sticking out. Put it up against the faceplate and spin it by hand. That will show you if you do have a problem.
 
My opinion is that while the alignment of the headstock to the bed may be adjustable (correctable), there should be no run-out in a shaft which is bearing mounted and rotates a piece of work at potentially high speed. The run-out at the point of a spur centre should be zero. I would second your idea about replacing the headstock (if it's new) or repairing it (if it's used).

cheers
 
"acceptable" is not a word used with regard to run-out on a lathe. It should be as near zero as is possible, probably to seven or eight decimal points. What make lathe is it? If you bought new, contact supplier and/or maker ASAP and demand exchange.
 
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