646-75lbh Restoration

[Eugen]

@Spike188 any words of advice on getting the swing cylinder(s) off the frame?

[Spike188]

Here are pictures of the swing assembly. To remover the swing cylinders, remove the swing arm 16 tooth pinon gear. It is held in place by 2 socket head set screws. Once it is off there are 4 clamps / 8 bolts that hold the swing cylinder in place.

[Eugen]

Eugene!

[Spike188]

The last post was March of 2023. I have been dragging energy wise since then but looking back to then, a lot has been accomplished. If only it could have been more.

One of the hold ups on this restoration is the axle housing wear. The PO ran it out of oil. The right hand axle has cut through the outboard bushing and into the housing at least 0.070". 2 machinist buddy's gave advise on a plan of action.

They loned me an angle plate and a small boring bar.

The challenge now is mounting the axle housing to the angle plate and getting enough mill throat to insert the bearing bar into the housing.

This is a mockup of my thought today. With the 6 stud bolts removed from the housing, it can be mounted to a 1" thick aluminum plate. The plate will be clamped to the angle plate. Alignment will be confirmed by inserting a 36" long shaft through the housing. After indicating parallelism the shaft will be removed and the axle can be bored.

[DavidBarkey]

If you have enough room in your mill ,that is a good plan of attack . I don't in my little mill , so I would have to make a line boring jig to do that job. Are you going to make an over-sized bushing or sleeve it ?

[Spike188]

@DavidBarkey You had suggested replacing the bushings with needle bearings. The the axles are about 0.010” oversize and 0.069” undersize for any bearing set my supplier found. Making axle sleeves to fit 32mm id bearings would not be an issue. Weight and thrust on the bearing was is a concern. The easy fix is to stay with bushings.

To answer your question about a sleeve or custom size bushing, My current thought is having a fly cutter or end mill made for the first pass. The length of a boring bar increases the throat size needed for the repair by a minimum of several inches. A custom size reamer for the finish pass would be a simple solution for the final pass in the axle housing. Making a custom bushing will eliminate one machining operation. I have a piece of bronze bar stock that will work for an oversize OD bushing.

Custom size end mills and reamers are easy for me to come by. My past 18 year has been as a service tec to automotive drill bit manufacturing machines. Often times an automotive bit or reamer at end of life can be sharpened and repurposed for other uses. Some of my customers have made custom step reamers for me in the past at little of no charge.