shims

[Lyndon S.]

When the early C 3 cars were built, did they use a frame that was dimensionally perfect to set the body on to get the number of shims? Did they do this for every car body that came down the line? What or how did they get two the number of shims needed for a given car?

[Edward J.]

Re: shims

Lyle, I believe that GM has a jig that is used and is dropped onto each frame and a measurement is taken at each mount. since the bird cage must be a precise and frame is not. each mounting point will require shims, I hope I have it right.

This process is also in the archives I think that John H. has explained this before.

[Paul O.]

Re: shims

Lyndon


The way John H. explained it was, the jig was lowered to a point that had 3 reference datum points to the frame not touching the frame. Then a line worker would use a stepped tool each step on the tool equaled to 1 shim. The number of steps that would go into that mount point was the amount of shims needed. Then with his grease pencil would mark the number needed at each mount point you could have zero shims at 1 or more mounts. I think John stated that the large hole on the drivers side of the frame outboard of the steering box was one of the datum points I do not recall the other points.


Paul 18046

[Michael H.]

Re: shims

The pic's below show the frame shim check fixture. The fixture is lowered into position and each mount location is measured with the tool shown in the third picture.

The entire procedure only took about 30-45 seconds.

[Domenic T.]

Re: shims

Paul & Michael,

That was what I needed to see, good post.

DOM