How do you turn brake hubs?

[o1marc]

What is the common process for turning brake drums on a bike. I'm told it has to be done after lacing and truing or truing the wheel will pull the hub out of round. This seems to me that every time you true a wheel it will need to be turned again because it will have been pulled out of round.

 

[jimmer]

Never really heard of the hub getting knocked out of round like that,but it does make sense. If I were doing it I would locate it on the bearing bore O.D on a rotary table on the vertical mill. I machined some cast wheel spokes that way and it worked slick. Not everyone has a lathe that can spin that large wheel diameter.

 

[Tim]

I can't imagine lacing a wheel to pull the hub out of round - the point is to pull the rim into round/true, suggesting the hub isn't going to flex. If it did, you'd never really be able to true a rim.

That being said, I also can't imagine turning a brake drum with the rim laced onto the hub.

These guys are the experts as I understand it - www.vintagebrake.com

 

[Rusnak_322]

If this were truly a thing, I have never heard of it. But it may be something that happened to 1940 or earlier racer bikes that used drum brakes and lightweight hubs and heavy steel rims and they were trying to optimize breaking performance.

With the meat on a factory hub from mid 60s on I can't see it being a issue.

 

[o1marc]

If it were that easy to flex a hub drum I would think you would have issues in every turn with the spokes flexing and making the drum do al kinds of things, braking would feel weird. I call BS on the whole thing. The thickness of the metal in a hub drum is not being moved because of spoke tension.