I have just replaced all the bearings and spindle in my CL3 lathe. Is it necessary to 'run in' the new bearings before use, in particular the phosphor bronze bearing? If so for how long and at what speed?

Yes it is advisable to run in your new replacement bronze bearing in your lathe as when originally purchased. Run in for two hours at medium speed, keep well lubricated and re-adjust the bearing when it becomes warm.
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