I joined this club today. I'm NOT Happy! (I'm Grumpy). ;)
Fortunately I found it while oiling the cups in preparation for our club's longest run of the year (tomorrow)
Seems strange that the end broke off. I wonder if the nut came loose or perhaps the keyway gave out...
No idea honestly. Didn't hit anything, pot holes etc.
Now that you mention it, it IS an odd place to break. The axle key was still in the hub and when I drove it out it looked ok.
You may want to check the inside of the wheel hub. If it has an interior shoulder defect, the hub may only be in contact with the end few inches of the axle. Over time the stress can cause the axle to fatigue and fracture. Best of luck.
How about some straight-on shots of the fracture? I'd like to see if was sudden or developing over a period of time.
Was it a reproduction axle?
Were you using axle shims?
Check your hubs for worn out tapers.
I second Walter's request for a well focused closeup of the fracture surface.
That's why safety hubs are a real good idea on any car that gets driven a lot. Think of the world of hurt that would cause going down the road at any speed. glad you found it when you did.
Looking at the stub left over, it has double set of holes for cotter to the axle nut.
Infers to me that is a very worn axle or hub, in that the nut had to be turned in well past the original cotter hole. That tapered end needs to match the hub well, otherwise some toggle load can occur.
A used Ford axle can only provide so much service.
I knew there was a 2-piece crankshaft club to join, I never knew there was a broken axle club to join. Just one more thing to worry about. Thank you.
Iím guessing axle shaft breaks were common back in the day. I have several axle housing with the bottom of the brake backing with a flat ground into it.
If you want a car that breaks axle shafts, try a Chevy 490 with a leather faced cone clutch. A lot of 490's running today use modified Ford TT axle shafts and modern clutch facing.
It used to happen to plymouths made in the 30's and 40's too!
I would suspect the key might have been too tight and the side of the hub toward the backing plate was tight but the outer edge was loose causing metal fatigue at the point of break.
Original Ford axles are now at least about 80 years old. Metal fatigue sets in. On the photos you can see lots of wear which suggests at some point things were moving about a bit. Axles break all the time.
Yes floating hubs are great, but not sure I could cut down the housing on my 12. Also have seen two floating hubs come apart on tours.
No solution is perfect.
Here's my application for the club. Happened last year.
I'll work on the photo you asked for. Yes, I had used axle shims.
Closer inspection indicated that the break was the final straw and an earlier crack appeared to be evident.
I never noticed the second cotter key hole. Must be blinder than I thought!
The use of shims tells me that the axle or hub taper was worn. Being worn, there was not 100% contact between the axle and hub across the entire taper. That created concentrated pressure points at the limited areas of contact. In your case, it looks as if all of the driving/braking forces were exerted only on the small end of the taper, leading to high stress concentrations at that end.