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Discussion Starter #1 (Edited)
Rebuilding the front suspension of my ‘71 Spider. Removed the lower A-arms and bought some Akron brand replacement bushings. I laid out the new parts (with the foam ring, washers and nut) in the orientation that makes sense to me. (Note: the washers and nut are arranged just as they were when I removed them).

Looking for confirmation from the group.

P.S. I have no ego with my Alfa so if I am incorrect, I have no problem being enlightened. Thank you!
 

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That is the correct assembly order for the parts. Just make sure that the countersink on the innermost washer (arrow) is facing the flange of the "dog bone" rather than the bushing. That provides clearance for the machined radius in the dog bone. And of course the outermost washer should be oriented with the opening of the cup towards the nut, so that it can be bent to lock the nut. I don't know if there's a specific right or wrong orientation for the bushing itself; mine came with the plastic ring already assembled onto one side, and I've kept that orientation.
 

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Here you go.

1617401
 

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Discussion Starter #6
Again thank you for your help with the a-arm bushings assembly. Your tip about the inner-most washer (adjacent to the foam (or plastic) washer) is well taken. The chamfer on one side of the washer mates with the generous radius on the base of the bushing shaft on the dogbone.
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Glad it helped. And I suspect that radius is there for a couple of reasons -- one, it's easier to manufacture than machining or grinding a sharp 90 degree corner, but more importantly, the radius provides a stress relief to avoid cracking in a part that's under load. Similar to the radii on crankshaft journals.
 

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Discussion Starter #8
Yep, I’m sure both factors influenced that detail in the design. I’m thinking the reduced stress concentration enables them to meet overall stress cracking and fatigue cracking resistance.
 

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Glad it helped. And I suspect that radius is there for a couple of reasons -- one, it's easier to manufacture than machining or grinding a sharp 90 degree corner, but more importantly, the radius provides a stress relief to avoid cracking in a part that's under load. Similar to the radii on crankshaft journals.
I'm not sure the radius is easier to produce. In fact to do it correctly as it must be for good engineering practice I believe it requires more attention to detail. That radius is there for only reason as a stress reliever. If it was easier why would some disreputable crankshaft grinders ruin good cranks by square cutting and removing radii when regrinding.

Ken
 

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I think you're right, Ken. My point was that it is actually difficult to maintain a perfect, sharp 90 degree inside "corner" in production because the tip of the lathe tool or grinding wheel will tend to wear and fight that. But it probably wouldn't be hard to keep a small a radius that would clear a normal flat washer but wouldn't provide significant strain relief. So yes, that radius is clearly there for strain relief.
 
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