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Advice needed on damaged wishbone bracket

640 views 4 replies 4 participants last post by  _alvin_ 
#1 · (Edited)
Well, I've deferred doing the RTA bushings and started to replace my front wishbone trailing arm bushes and I've had to send myself to the naughty corner, but first I need some advice.

I've got the first bush off the wishbone without too much trouble, but on carefully cutting a notch in the large outer bush ring to knock the ring out, i've stupidly slightly nicked the inside edge of the wishbone bracket on one edge.

I'd say the groove would be somewhere between a 1/16" and 1/32" deep and runs for approx 1/4 of an inch.

Should I throw away/does this part need to be without flaws or subjected to stress that needs the metal to be complete, or is it safe to leave as is?

I just have bad memories of a particular racing mag alloy wheel from a motor bike many years ago that should not have been used on the road and consequently it occasionally disintegrated on some riders due to small flaws from stress cracks weakening the material.

Any advice would be appreciated
 
#2 ·
You should be fine. There's lots of material in the brackets, and the type of stresses in addition to the bushing material absorbing a lot of those stresses, shouldn't cause any problems like stress-fracturing or anything like that.

As long as the replacement bushing presses in tightly everything should be okay.
 
#3 ·
When cutting something like that, such as RSBs or RTABs, it's advisable to cut towards the heavy part of the hole, not the thin part. If you've done that, I wouldn't worry at all.
Even if you've notched the thin part, what you describe seems too small to worry about. The stress there is not very much and there is plenty of margin.
 
#4 ·
I've got the first bush off the wishbone without too much trouble, but on carefully cutting a notch in the large outer bush ring to knock the ring out, i've stupidly slightly nicked the inside edge of the wishbone bracket on one edge.
If you are talking about the removable bracket that the rubber bushing is pressed into, I would just note that once the new bushing is pressed in you will not be able to see the "nick" or its condition if it starts to expand, failure of the bracket will likely cause some significant control issues if it fails while driving the car, and the bracket is a fairly inexpensive part (some folks change them when they change the bushings by buying the bushing already installed in a new bracket).
 
#5 · (Edited)
If you are talking about the removable bracket that the rubber bushing is pressed into
Yep, that's the one.

...failure of the bracket will likely cause some significant control issues if it fails while driving the car,...
Yes well thanks BeemerMikeTX, you've certainly touched on my worst fear.

I've had a rethink last night. Yesterday I cleaned off any oil and patched some meta/araldite into the small crevice. I think I'll now take a very small rat tail/round file and work the edges into a narrow hollow and then buff/fine wet & dry, to soften the small gash into a small/gently sloped valley, which will hopefully stop that being a weak spot... then maybe order a new one?!

The bushes going in are the Powerflex ones, so hopefully easy on and off if I in fact get a new bracket, but I'm open to advice from someone with a racing/engineering perspective as to whether this fix is in fact fine long term as dkindig and Blacklane above believe.
 
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