wishbone failure
ruskino80 - 19/9/15 at 06:43 AM
Just came across this on mk indys facebook.
https://www.facebook.com/photo.php?fbid=10153044376190308&set=pcb.10153106888593314&type=1&relevant_count=4
theprisioner - 19/9/15 at 08:07 AM
If it is broken like that, is it because the tube it is made out of has a seam?
Talon Motorsport - 19/9/15 at 09:06 AM
It looks a bit on thin side to me maybe 1.2-1.6mm? Personally I like to go for the overkill approach it seems to be safer in the long run, I make sure
all the seams on my bush tubes have the 'leg' section welded across it.
40inches - 19/9/15 at 09:34 AM
Usual cause, in the past, has been the outer tube being tight in the brackets, not allowing the bush to pivot on the central tube.
Slimy38 - 19/9/15 at 11:56 AM
quote:
Originally posted by 40inches
Usual cause, in the past, has been the outer tube being tight in the brackets, not allowing the bush to pivot on the central tube.
The full post suggests they had checked all the joints earlier as a possible cause of another fault, but they were found to be free.
Having said that, I don't understand why the inner face is so mucky. That does suggest the bush tube and the bush weren't in permanent
contact, and as you say it meant the bush tube was revolving around the bush rather than the bush revolving around the central crush tube.
liam.mccaffrey - 19/9/15 at 12:30 PM
Heat affected zone failure.
MikeRJ - 19/9/15 at 02:56 PM
quote:
Originally posted by liam.mccaffrey
Heat affected zone failure.
It's undoubtedly failed at the HAZ since that's the weak point, but that's not the actual cause otherwise the entire chassis would fall
apart.
Probably either a steel crush tube that rusted and seized in the bush, or the bush was a bit too wide for the chassis brackets and caused binding with
the bolt tightened up. Those two problems have been the primary cause of numerous failures like this.
myke pocock - 19/9/15 at 03:22 PM
When I made my bush tubes I used thick wall seamless and skimmed the ID to the required size meaning I got the ID I wanted and probably a bit thicker
wall thickness as well.