How best to repair this (worn pin hole)?

[m_c]

We've finally had to fix the steering rams on the old forklift that uses JCB axles, which involves removing the axle, as you can't get the inner pins out with the axle in place.
So while it's off, I'll be changing all the seals, but having removed the track rod, it's revealed most of the play is due to somebody fitting too short a pin, so it's worn the hub carrier.

To add to the problem, I currently don't have a functioning mill big enough to hold the casting.

 

[8ob]

A big drill and sleeve it back to size

Bob

 

[m_c]

A big drill and sleeve it back to size

Bob

My concern with that approach is that it'll involve removing quite a big amount of good material.

 

[chrismac]

My concern with that approach is that it'll involve removing quite a big amount of good material.

The beauty is though, if it need bushed again you only need to replace the bush no drilling again and your back to your correct pin size.

 

[Agroshield]

My concern with that approach is that it'll involve removing quite a big amount of good material.

If the wear is not concentric to the pin, you could use an eccentric bush to minimise work to the original.

If the pin was too short, does that mean the excess wear is only part-depth of the hole? If so, could a top hat bush be an option?

However, not being able to put the part on the mill makes both of these more difficult options than a simple concentric bush.

For the eccentric bush, you would have to make the hole round (and not worry too much about its concentricity with the pin), push a slug into it, mark the centre of the pin, dial that mark in with a four jaw and bore the hole for the pin eccentric to the slug OD. Loctiting the bush into the axle would allow it use the pin to self-align (it would be near impossible to press it in and maintain the correct clock position).

Edit: please say what machining facilities you do have. If the top hole is not too bad, that would be do-able with a lathe and decent (Morse taper spindle) drill press. Bolt the axle to the DP table with lower hole upwards (i.e. upside down). Turn up a rod on lathe that fits the top hole and fits a Jacobs chuck the other end. Use rod to make pivot hole concentric with drill press spindle. Use boring head in drill press.

Another wild idea is to use a mag drill to power the cutting tool. Again, make it concentric with the good hole using a rod turned on the lathe (so its top end would be 3/4" diameter). Magnet the drill to a thick plate and tack weld the plate to the axle where it touches so it is 90 degrees to the hole centreline. You might need an extension for the rotabroach bit to reach the lower hole, but that is what the lathe is for. It would be easier to use an axle casting to hold a magnetic drill than to hang/suspend the axle casting in mid air so it can be secured to a drill press.

 

[Bornfree]

These axles are on the little 520 loadalls. The expensive way is to take it somewhere with a large mill have it bored and sleeved. The cheap way is a new pin and weld it top and bottom.quick spray with some jcb yellow and no one will ever know.

 

[awemawson]

Line bore it.

Watch Oliver Snowball (Snowball Engineering) on YouTube

 

[Agroshield]

Watch Oliver Snowball (Snowball Engineering) on YouTube

...who only ever linebores stuff that will not fit on one of the machines he owns.

Lineboring is in-situ machining, which is a long way down the list of possibilities and only becomes worth the hassle when all reasonable take-the-piece-to-the-machine options have been exhausted.

 

[Dozzer]

It all depends on how permanent you want the repair?
Quick & dirty = drill out hole. make bushing bit smaller than hole drilled with chamfer top & bottom. use pin to align with top hole, weld in place.

Long term & expensive = have it machined, and a decent sleeve nitrogened into place then hone.

Farm method = weld up hole and use rotabroach to size hole back to "good enough" tolerances, then carry on using it (adding some baling twine) just in case it drops off

 

[8ob]

It’s a simple fix, tackweld or clamp a lump of flat plate to the housing and drill/bore out with a mag drill, spin up a couple of bushes and press them in. I reckon that’s a mornings work all in.

Bob

 

[zzr1200]

When I worked for Lansings forklifts, we welded up the worn surfaces, slid the pin in the upper hole and used a die grinder/angle grinder to machine the surfaces/hole.....() to fit. Rose joints help with slight mis-alignment at times....