Polish Axle Tapers?

[Deuce Man]

Hey guys, filing burs off will help, but lapping the hub to the axle with valve grinding compound is the secret. Rich

 

[Bob Bidonde]

The key reacts the maximum torque of the engine, the shock loads of popping the clutch and it reacts the service brake torque. There is no way the taper alone can do this. I believe the function of the taper is to assure concentricity of the floating axle with the axle housing and drum assembly.

The fit of the key into the shaft and drum hub needs to be snug for shear transfer efficiency. If the key is not snug, deformation of the slots in the drum hub and axle will occur eventually leading to a failure. On the other hand, the key material needs to have mechanical properties (strength & fit) equivalent to the original Ford key.

The maximum stress (torsional shear) in the axle shaft is at its outer surface. The keyway slot at the beginning of the taper is a stress riser and the most likely place for a fatigue crack to initiate.

 

[katy]

and axle nut is tightened per specs,

So what is the proper torque?

TIA, Ken

 

[Deuce Man]

Hey Bob, Better do a little research, maybe check an engineering manual. We deal with german diesel engines where the flywheel is attached to the end of the crankshaft with a taper about five inches long and four to five inches in diameter, No bolts, no threads, no keyways. just pressed on , and they never come off or loosen up
These engines put out 1400 horsepower and 3500 ft. lbs. of torque. nuff said, Rich

 

[TBone69]

I'll be heading over to my buddy's shop later to clean up the axles and should have some updates this evening.

When it comes time to install the drums I will lap the hubs to the axles for a final fit.

As for the drive shaft I have another that I saved and need to pull the pinion to check out he taper.

 

[Deuce Man]

T bone, make sure you have the proper amount of torque on the nut, dont lube the taper, just clean it real well of all valve grinding compound, By the way you will be able to see real clearly how much contact you have when you start lapping the two together Rich

 

[TBone69]

Couple days late but here they are. I polished up 4 axles and will use the best two.

My buddy also hooked me up with a nice Armstrong 0-50 inch lb torque wrench and I raided his tooling and came home with a live center for my lathe, heck it was too small for his lathe anyways.

These are the worst two, before and after pics

 

[TBone69]

Here are the better of the two axles before and after polishing. I'll finish them up lapping on the hubs.

I still need to give them a good cleaning, spent the day today making the carrier pre load tool.

 

[PC/SR]

That's really nice work, but I say again, make sure the hub ends extend over the threads.

 

[TBone69]

I did have to use a puller to remove the drums when I disassembled the rears but I will double check them.