Aurora Rod End failures

[markm]

hey hey

i was wondering if any other teams out there have experienced many rod end failures.

it would be nice to know if this has happened much before or if it is something we need to change in the suspension set up

[markm]

hey hey

i was wondering if any other teams out there have experienced many rod end failures.

it would be nice to know if this has happened much before or if it is something we need to change in the suspension set up

[Ben Steele]

Did you break a rod end or is your question preemptive?

[Denny Trimble]

The only rodend we've broken in my memory is:

5/16" (shank and bore), non-teflon, mounted on a pushrod (in compression!). We didn't lubricate it, and drove in the rain a few times. Apparently we should have lubricated it, because the rodend mounted between the pushrod and bellcrank seized up. The head of the rodend twisted with the bellcrank and broke the shank, causing a nasty spin and lots of collateral damage (halfshaft, a-arms, frame, swaybar, etc) just before competition in '99.

[Kevin Hayward]

Mark,

We have beaten out the teflon lining on a AB (or AM) 5/16" bearing on a toe link. We put the large cyclic loads down to a little too much scrub on the rear suspension. Replaced it with a PRM (I think) of the same size and haven't had a problem since. It has a better quality teflon lining.

I don't know if that is the broken you're talking about though.

Kev

[markm]

we have broken 2 6mm rodends now
snapped them both 2 threads below the spherical at the rocker end of the front pullrod

i think maybe we should just move up to a bigger size and it will be fine

[Angry Joe]

Edit: Missed your second post

[Big D]

we broke one or two in the trailer on the way home, 1/4" rod ends used at the chassis side of the rear A-arms. But I guess, any of you who saw the U of S car at competition, know it is obscenely wide, our rear arms are a mile long, so that may have something to do with it. I myself am freaked out by threads being used for anything but clamping two parts together.

[Frank]

are they heat treated items?

I find it very hard to believe after doing a bit of tensile testing on various rod ends

and what angle is the pullrod to the horizontal plane, ie is this the cause?

and what did you hit?

Frank

[Kevin Hayward]

Compressive tests on Aurora AB-4Ts at full extension (with 10mm engaged thread) show failure loads of around 17kN. This is pretty large.

Are you putting the threads into bending in some way? Or is there eccentricity in your pushrods? Maybe you are binding up somehow. What rods are you using?

In tension the rods are considerably better at dealing with loads.

Kev