[Pete]

Dial indicate half then turn it around and do the other end. As long as it runs true in the chuck and the tail center runs true, you should be able to check it ok.

I used heat to straighten it. Heat it on the high side and cool quick with a wet rag or if the lathe has coolant use that. DO NOT heat it enough to turn it color. It will usually take several times to get it straight. Be sure to dial it over the whole length.