Subject: RE:Where to get heim rod ends? by BillH on 2008/1/25 16:24:26
Quote:
Hmm. I wonder how much load those rods can possibly see? Lighter is better if I can get away with it.
A grade 8 bolt is good for about 120,000 psi in tension at the thread root. But they'll fail in tension at about 23,200 psi under fatigue. Grade 5 bolts are good for about 18,600 psi under fatigue.
Looks like they usually snap at the first engaged thread. After 6 or 7 threads, the rest don't carry any load at all. Of course they're preloaded too. Overtightening them reduces how much load the link can carry.
Hard to find info about thread strength. If they're in an aluminum link, the threads may strip first.
One thing on measurements, what I usually use on thread engagement is to thread the rod in using up 5/8 to 3/4 of the total thread length ans leave the rest of the threads for adjustment. I read that somewhere, long ago.
