material failure - AL

[Welderd]

here's a break to analyze


7075 link

[/QUOTE]


I think they was turned down too much

but I still don't think it shoulda broke like that

Did I get me some bad material?
I have more and I'm gonna remake the link but with no neck down

 

[John Galbreath Jr.]

There is some alumnum that is very brittle. Don't remember the numbers. There was a recent thread on Pirate.

 

[InDaShop]

7075 turned down to much for the size they were tapped too.

How long were your links? Something stupid long correct?
Sell them on Pirate to someone needing link material shorter than the turned down area on of your links.
Use the funds to buy new material to tap, and not turn the ends down on.

 

[Welderd]

front link material was like 38" I think

length didn't play a part in the failure near the end
after thinking about it - I was worried that the shear strength of the turned down portion would be an issue, seems it was, but that doesn't seem like a shear failure, more like a fracture

I have more material - from the same lot - wondering if it's got internal cracking or if a crack started in the threads

I'll make 2 new front ones, replace broke one and other one and keep other one for spare
then I'll take the broke one and make it for the rear which is shorter and replace one of the rear ones and keep it as a spare. the rears should be harder to get a direct impact on them like that

 

[InDaShop]

I didnt mean the length had anytghing to do with it at all. My thought was......if your links are 38" and 4"s on each end are scrap. Sell somebody 30" links of the usable material, and make yourself new ones that aren't machined down.

BTW I know someone that could have used 30" link material until I bought 24 feet of 2" 7075.

 

[Welderd]

gotcha - I need 28" rear pieces ;D

 

[P]

I think it got pissed off at your quirky suspension and rejected itself from your buggy...


flippin ya ****... in the video it really didnt seem like it should have failed were it did, first glance you'd suspect the neck down obviously I bet it started to crack initially up front were the threads begin and broke off from there. Have you checked the others to see if they have any damage at the skinniest point ( were the threads begin and the neckdown meets them )

 

[Welderd]

I'm gonna bring the broken piece into work and have some of these "aerospace engineers" take a look at it. They'll probably piss and moan that it's not for work. I bet most of them have never seen broken material before though and they'll just draw me a stress/strain curve and confuse the **** outta me with theory

 

[6uldv8]

I'm no expert but I work with metal everyday. Regardless of the aluminum grade it looks to me to be turned too thin on the ends and that's right where the leverage of your rod ends is applied. Looks like it started at the tip and peeled back. Aluminum is also prone to stretching and even stress cracking.

 

[P]

I'm no expert but I work with metal everyday.

laughing1 that made me laugh outloud for some reason... I guess I didnt expect it

 

[kid rok]

just don't turn the ends down, I ran 6061 for a while on my old rig and never broke like that. I actually never broke a link at all. I had one to pull out , but I didn't keep the jam bolts tight so it was eventually going to happen.

 

[muchado]

welder it back together yourself!!


Does square have anything to do with it?

 

[draggbody]

laughing1 that made me laugh outloud for some reason... I guess I didnt expect it

you guys are the most subtle cross posting mofos ever... pirate4x4.com/cliffnotes rules....

 

[6uldv8]

I'm no metal expert but I did stay at a Holiday Inn Express last night!

 

[Welderd]

new ones won't be turned down at all

square material didn't hurt it in this application - actually they are stronger than round for link bending but not if too much material is removed