Front Axle Seminar - SCMAFC

Front Axle Seminar

About a dozen Club members met in the S.A.I.T. automotive shop facility on the morning of December 1/01. Our host was Bill Davidson, an automotive instructor, well known for his knowledge of Model A mechanics. Bill began his presentation by explaining some of the characteristics of metal, it's elasticity properties and cautioned that an axle should never be heated beyond a dull cherry red colour. He explained the geometry of the Model A front end and the important part that the front axle plays in it.

Members in attendance had been asked to bring along axles that needed repair and we had a total of five, including one that still had stubborn spindles attached and one still attached to it's radius rod. With a combination of heat, hammering, pressing and some good old elbow grease and a large bench vise Bill showed us how to separate these components successfully.

Bill explained the techniques that he would use to repair our axles and demonstrated the use of a few tools that he has built for this purpose. He has a pair of straight welding rods, about three feet long that are equipped with tapered metal cones with locking bolts that can be attached to the axle through the king pin holes. By sighting from the side, it is easy to see the alignment of the axle ends and what adjustments are necessary.
He also has a horizontal bar assembly that has legs that sits on the axle. This unit has a sliding protractor at each end that is used in conjunction with the rods to check the alignment of the king pin holes. Bill explained that he would adjust the axle for a 7 degree camber setting.
One by one, each of the five axles was checked for existing conditions and then adjusted accordingly by applying just the right amount of force on the axle in a hydraulic press. This process involved pressing a bit at a time, usually rapping the axle with a heavy hammer several times while it was under pressure. After each visit to the press Bill would set the axle up and check the progress with the rods and protractors. We were able to assist in this checking stage and were quite amazed at the good results that were attained.

All of the axles had the usual wear in the king pin holes and Bill was able to shrink these slightly by applying heat and striking them on the outside with a large hammer. He then used a reamer to clean the holes out and checked the fit with a new set of king pins.

I think everyone in attendance learned a lot from this practical 'hands on' session and we would like to thank Bill Davidson and Murray Walkemeyer for all their efforts in arranging it. Pictures and a video were done by Dan Johnson.

-- Al Friesen