I needed to replace a broken spring leaf on the rear of my '13. I also had another taper leaf rear spring with a broken leaf. So this morning I went to our local spring manufacturer (Standens Ltd.). I bought two pieces of the appropriate spring steel. They told me if I had it back by this evening, that should get my two new leaves on Friday. It is already tempered, so I had to use a carbide insert milling head and a carbide drill bit to drill the centre hole.
It took about two hours to taper the 4 ends, drill the holes and do a bit of cleanup grinding. Actually by the second leaf I had it down to about 15 minutes per end. I found that taking a .015" cut worked nicely.
If it's one of the lower leaves it needs quite a complicated bending too. Are the 1918-27 springs so off in the shape that they can't get milled ends and fitted into a 1909-17 tapered stack?
By the way, I wonder how Ford made them? Forged ends before tempering, perhaps.
I believe the way they were made was the profile was hot rolled into them from the centre out. The position of one of the two contouring rolls was controlled by a cam thus squeezing the material thinner as it progressed along the leaf, side rolls controlled lateral spread. Then the ends were clipped to form the rounded end. Modern single leaf springs are made the same way on similar machines with cnc control for the contouring roll. Shot peening then follows.
I certainly believe you are correct on the process Ford used. The method I'm using has been done before. They were totally comfortable on the "shaping " required. Considering they have been in the business for many many years I think I'll be OK
Roger. I really didn't have any other rear springs I wished to "sacrifice ". So far I'm into getting 2 leaves for about $30.00. Obviously the shaping will add some cost