Can I grind clean a worn leaf spring?

[Great Lakes Greg]

I can see where the individual leaves have rubbed a notch into the respective leaves they ride on. They are not deep and I am thinking of just grinding the area smooth so they slide instead of hit the notches and stop. Any harm in this? I also found a broken leaf, and I have a want add seeking one. Thanks everybody.

 

[BRENT in 10-uh-C]

Yes you can however be prudent to what is too thin in that area.

.

 

[Ron in Quincy]

If you are talking about the rear spring, yes it is a good idea to dress the grooves smooth in the top of the leafs; you can also bevel the ends of the leafs on the bottom side which will allow the leafs to slide much easier without putting stress on any one leaf. I have done this to several rear springs when rebuilding and have never had any future problems.

Ron

 

[Jim Parker Toronto]

Yes, but use a coarse sanding disc on a rubber backing plate. The solid grinding disc would be a little harsh. Turn each leaf over, and round off or bevel the leading edges. Paint just the edges and the part of the spring that you can see, and after drying, coat the other surfaces with a mix of graphite and oil. It will last another 80 years!

 

[Pete]

Here is a blurb that I answered to a similar question on the HAMB


First, inspect the top of all the leaves for grooving.
If grooved, grind and taper the tops of all the leaves for the last 3 inches. Bevel the bottoms up slightly also.
Just enough so there isn't a sharp edge rubbing the leaf below it.
The number of leaves you use will depend on the final weight of the car
and the "ride" you want. On a typical model A rod it is possible to get a
100 lb. per inch spring rate. Have the shocks disconnected when checking spring rates.
I parkerize the leaves before assembly. It makes the surface smoother and slows rust down.
I use 1/16 UHMW plastic between the leaves.This is the same as Teflon but about 1/3 the price.
After determining the final configuration of the spring I wrap it with black electrical tape
from the eyes to the U bolts. This keeps dirt out.
If you use a reversed eye main leaf, be sure the second leaf is short enough that there
is no way it can bottom on the eye when at full compression.
Sometimes the original spring clips will not reach over the spring after the UHMW is added.
It is a simple matter to fabricate ones that will.
The inside top of the cross member where the spring seats, usually has a radius.
BE SURE the top leaf of the spring has a radius to match. a sharp corner on the spring
leaf can cause a cracked cross member.
I use moly filled Delrin shackle bushings (home made) because they have almost no friction and they never wear out.

 

[dave in australia]

I've removed the grooves with a linisher belt. Use a herringbone pattern for the first cut, then finish with a fine grit and in the direction of leaf travel (length ways). Then on the lower side of the leaf, round off the nose, starting about 3/8" from the end. Afterwards lubricate with dry lube, assemble and paint or paint then wet lube then assemble. From what I've read on this forum, both methods work well, although I prefer dry lube as it doesn't hold dust and dirt. One tip is to use a new centre bolt and don't use it to draw the leafs together. I use a shop press to hold the leafs together whilst I fit the centre bolt, others have different methods but the rear spring is lethal when it's under tension, or is that compression.