Reproduction inner and outer brass axle bushings?

[foxfab]

Nick, what do you think about making a press fit steel sleeve for the outer stub shaft and use the readily available bushings? We'd probably have to have the worn shafts trued by turning them down a bit for the new sleeve.

The inner brass bushing will have to be made.

 

[IDave]

That's fine, and it's good to know you think the brake hone approach is OK, Nick.

 

[zebrabeefj40]

Mike, I think the best way to sleeve the shafts is to turn the shaft back to round, straight and clean. Then make a sleeve to fit with only the bore finished. Shrink/press the sleeve onto the axle shaft. Finally, turn the sleeve to size after it has cooled and shunk to final size. IMHO that's the only way you will get a bearing surface that will run true to the axle shaft. It's not as easy as a Speedi Sleeve because you are trying to repair a bearing surface not just a seal surface. Bearing surfaces will see much higher loading than a simple lip seal will apply.

What kind of wear pattern are you finding on the shafts? Can you post of a pic of the bearing area? I've only pulled apart birfield axles. I understand how the ball and claw stuff works but I have not actually looked at the guts of one of those axles.

Another option for shaft repair is to have a shop build up the shaft with weld and/or chrome plate then regrind to size. I've seen this done on machine tool parts and it works well. Will also help maintain the strength of the axle shaft vs. sleeving. For a sleeve to work the diameter of the axle shaft is turned down. The sleeve does not return the shaft to a strength equivalent to solid bar. All sleeving provides is a new surface of the correct diameter for bearings

Something else to consider: if new bushings were made it is easy to add an o-ring to the bushing to help with oil control. Or a seal could be fitted to the diff side of the inner bushing to control the oil vs. the screw threads in the bushing (the screw threads are pretty easy to machine though).

What benefit do you see of sleeves vs. fitting new bushings? Maybe I missed something in the earlier discussion...

Nick

 

[foxfab]

No benefit other than we thought it might be cheaper and would repair a bearing surface that might be out of round or scored.

Arent the screw threads required to lubricate the bushing with a little gear oil?

 

[zebrabeefj40]

I am not sure but I am guessing that since the axle turns it will still be round even if it's worn. The bushings, being fixed, will see side loads from steering that will cause the bushings to go oval instead of round. But I don't have any examples to check.

On the bushing lube: I assumed the screw threads were installed in the truck to carry the gear oil AWAY from the knuckle. You showed left and right handed bushings. Which way do the screw threads run on each side of the truck? Or, assuming the truck were traveling forward and the axle spinning, would oil be drawn into the bushing or pushed out?

I figured that if I cut an o-ring groove in the flange end and threaded the bushing that oil could lube the bushing. If I used a seal on the diff side of the bushing then the greese from the knuckle could lube the bushing like it does in the spindle side. Or I could duplicate the stock bushings and it'll keep going long after we're all dead!


Nick