Left and right radius arms the same? Or did I bend them? (1 Viewer)

[mudgudgeon]

It isn't voodoo magic, but you are correct that you maybe shouldn't modify critical suspension parts without some understanding of what you're doing.

There are hard rules of reduction percentage used in forming metal, but I'm struggling with how to explain it well in a way that relates to bending 80 series radius arms.


The op is very safe to straighten his bent arms and run them.

Why do arms break when wheeling?

How is that different from bending in a press?

 

[PIP]

Why do arms break when wheeling?

How is that different from bending in a press?

A press is a slow, controlled process. Moderate force over a duration of maybe 10 seconds. The force from the punch is distributed across the die opening.

Take the mass of your cruiser times the velocity its traveling applied to a concentrated area on one radius arm where it slams into a rock.

I've never seen one fail. Just guessing without seeing the broken arm and exactly what happened to it.

 

[BILT4ME]

A press is a slow, controlled process. Moderate force over a duration of maybe 10 seconds. The force from the punch is distributed across the die opening.

Take the mass of your cruiser times the velocity its traveling applied to a concentrated area on one radius arm where it slams into a rock.

I've never seen one fail. Just guessing without seeing the broken arm and exactly what happened to it.

Just say:
"It's ok because of service factors calculated into the design" and move on.

That's how most explain it to those of us "lesser people "......

No offense taken or implied......

 

[mudgudgeon]

A press is a slow, controlled process. Moderate force over a duration of maybe 10 seconds. The force from the punch is distributed across the die opening.

Take the mass of your cruiser times the velocity its traveling applied to a concentrated area on one radius arm where it slams into a rock.

I've never seen one fail. Just guessing without seeing the broken arm and exactly what happened to it.

I haven't personally seen a failure. Have wheeled with guys in the past that have broken them. And seen pics.

Not questioning your knowledge, just always curious.

Of breakages I know of, they are on rigs that were wheeled hard. Not necessarily at high speeds.
So my thoughts are repeatedly stressed over a period of time. Metal fatigue or work hardening. Or material failure due to manufacturing differences?

Is there a way to check if a used part is close to its limit before you put it in a press? Or you're just assuming it's still good because you "know" what it's made of?


Why do some bolts fail, others don't in the same installation?
I figure there's differences inmaterials within a tolerance range during manufacturing.
(I did a construction project on a warehouse that housed QA testing for fasteners made in Thailand, they rejected literal tonnes of fasteners every week, they tested a certain number per 1000/ batch. If the test sample failed, the whole batch was scrapped).

 

[mudgudgeon]

Just say:
"It's ok because of service factors calculated into the design" and move on.

That's how most explain it to those of us "lesser people "......

No offense taken or implied......

Spoken like an engineer!!


What happened to you man!? You've changed!

 

[PIP]

I haven't personally seen a failure. Have wheeled with guys in the past that have broken them. And seen pics.

Not questioning your knowledge, just always curious.

Of breakages I know of, they are on rigs that were wheeled hard. Not necessarily at high speeds.
So my thoughts are repeatedly stressed over a period of time. Metal fatigue or work hardening. Or material failure due to manufacturing differences?

Is there a way to check if a used part is close to its limit before you put it in a press? Or you're just assuming it's still good because you "know" what it's made of?


Why do some bolts fail, others don't in the same installation?
I figure there's differences inmaterials within a tolerance range during manufacturing.
(I did a construction project on a warehouse that housed QA testing for fasteners made in Thailand, they rejected literal tonnes of fasteners every week, they tested a certain number per 1000/ batch. If the test sample failed, the whole batch was scrapped).

I guess basically, yes, we know what the characteristics of the material are so we know how much we can modify it without compromising the design.

If I bend a radius arm 4 degrees and the crossection is reduced at bend mid-point by .02% is it still roadworthy at 99.98% strength?

 

[mudgudgeon]

Sounds like probably