A question for the bearings experts: Is it possible that the ball bearing design contributed to the frequent cracking of the early hubs, or is the hub design 100% at fault? Was the greatly reduced incidences of cracking solely due to the new style hubs' shorter threaded section, or was it the new roller bearing design that was introduced at about the same time?
I don't think they crack because of the ball bearing. They are just plain thin where the bearing race is. The later hubs have far less threaded area for the hub cap, resulting in a stronger support for the bearing race on the hub cap side.
Note that ball bearings continued to be used on non - starter equipped cars even with the later hubs through 1926. We don't see any more cracking in hubs with ball bearings or with roller bearings, but occasionally the late hubs do crack in the hub cap threads.
I kinda solved the problem on my '13 touring. Years ago, I had a machinist friend take some late hubs and thread them back further. That way I can use Timken bearings. Fast forward, I recently acquired a '13 runabout with ball bearing hubs. I had a NOS set of ball bearings, and never having used any, I decided to give them a try. I have noticed some early hubs have the slot for driving out the races, and some don't.
At some point someone installed a Timken race in one of those early hubs, and the only way I could remove it was to weld a washer across the race so I could drive it out. The car now has ball bearings, I like them. They are big enough to support a much heavier vehicle.
We use the original hubs and ball bearings n our N, K and 09 T. So far, no problems, and we put a fair number of miles on. (I'm going to knock on wood)
Ball bearings were used in the chevys I know thru 57, held up well and those were heavy compared to a T. KGB
I feel that any cracking or damaged hubs was caused by lack of maintenance. The early hubs were designed for ball bearings. In the early days these hubs were subject to considerable foreign materials, dust, dirt and water and were only protected by a 1/4" thick felt. These felts required to be replaced regularly and the bearings repacked with grease. Most of this maintenance was never done, bearing races wore out severely and consequently cracked the housings, not the housing's fault. Some after market entrepreneur promoted roller bearings to avoid the perceived failures. With some of the early conversions the roller assemblies were too long and stuck out and were exposed to the same elements as the ball bearings. To solve this problem the hubs were redesigned with an additional 1/4" of material added to the threaded area (paper thin) and very susceptible to cracking. There was at least half a dozen hub manufacturers and as many after market makers. I have 6 or 8 hubs and none are exactly the same, and yes one of them is cracked. Some have a relief to drive the bearing race out and some don't. With some hobbyists roller bearings is the only way to go, others prefer ball bearings. I have a 100 year old car with ball bearings with no issues. Every year now is a 100th anniversary. I am fudging a bit mine is only 1915. Maby by the time it gets to 100 I may have a failure. Dave
We drove our 1915 roadster in the Ocean to Ocean tour in the summer of 09, a total of about 4,400 miles with ball bearing in the wheels and chain links in the speedometer cable housing. No problems with either.