A Bolt That Refuses To Bend Symmetrically

[EricMilfeld]

I bent a few 3/8 x 7" "HKT" bolts tonight. They all, despite my best efforts, finished with one leg an inch longer than the other. So then I got curious and calibrated one to thirty degrees, which produced a perfectly symmetrical "V" shape. I then finished bending the bolt by hand, and wouldn't you know it, it still ended up with one long being 3/4" longer than the other! Curious as to whether something crazy was happening with my technique, I bent a Shiny down past ninety and was left with a perfect "V". Has anyone else run across a bolt or nail like this that is predisposed to bend irregularly, apart from any technique issues. It made the crush rather difficult, as you can imagine. It calibrated at 515 pounds and measures 7 3/16" total length, by the way.

I'm wondering if one end of these bolts has somehow been hardened over at the crazy factory in China.

[Tim71]

Seems like I remember having a bolt I was going to use for scrolling and when I went to test one it actually bent up in my hand. The companion wrench is notorious for that but it's got a good excuse with the change in rib heighth.

Tim

[gazza]

Im guessing its the head part as thats the part they pull on to stretch test those bolts to see if the elogate anymore try cutting say the head plus 1/4-1/2inch off them and see if that makes a difference did the threads stay straight on them.

Dont forget also that they will be a mass produced bolt with varying quality control especially being made in china/korea were the wages are very low.

[gripmaniac]

Eric,

How much thread is there on the bolt? Just 1" ?

I'm curious as to where you're exerting pressure on the bolt. Right on the ends during sweep & crushdown? I've been known to give the head a miss when using mininal wrapping on tough 6" * 5/16" grade 2 bolts and that sometimes resulted in asymmertical results.

At the end of the day it could just be they're "made funny".

Dave

[EricMilfeld]

The threaded portion, which didn't bend the slightest, measures 1 3/8". It's the leg with the threads that always ends up 1" shorter than the other. If nothing else, they make good training tools for wrenches and other items which bend asymmetrically.

And yes, I'm using my typical double overhand technique, exerting force on the ends by gripping it with my first two fingers and thumb.

[Tim71]

Eric,

Try this, switch the head to your other hand and see if that makes any difference. I know it will feel weird. I actually switched my hand preference not long ago for whatever reason.

Since the threads didn't bend though I'd just bet that it was a manufacturing issue. You could always try to brace one and see if it still does that.

Have you bent any other 3/8 G2 bolts? How did they behave?

Later,

Tim

[EricMilfeld]

Tim, yes I've bent several other 3/8" bolts with no such stubborn behavior out of them. I think bracing it would be redundant, as I've already prekinked one to 30 degrees right on center, but it still finished 3/4" off center when I finished it by hand. I'll try switching the head around again, as I tried it yesterday after I was too pooped to do anything with it.

[Booyah!!!]

I'm going to have to try some of those when I find them at a hdwre store. Oh, if I can bend them

[EricMilfeld]

I did some further research today. First, I turned the bolt around and bent it with the head in my right hand with the same result. Then I cut off the head for a bend, but no difference. So, long story short, I found a bolt that basically bends at a point roughly 3" in from the threaded side. I was looking for an "easy" show bolt that looks intimidating. I guess it fits the bill, but it's still kind of weird having it come out like a "J".

[Booyah!!!]

Just tried them Eric. Is this what you are talking about? How strange

http://www.gripboard.com/index.php?autocom...si&img=6436

Edited October 23, 2007 by Booyah!!!

[EricMilfeld]

Just tried them Eric. Is this what you are talking about? How strange

http://www.gripboard.com/index.php?autocom...si&img=6436

Okay, now I know I'm not crazy! Thanks, Mike!

[lone Wolf]

Eric what does it calibrate at 6" ? Can we see if the 15% per half inch applies here ?

[EricMilfeld]

Eric what does it calibrate at 6" ? Can we see if the 15% per half inch applies here ?

Sure, I can do this. And there's no telling with this wacky, crazy bolt. I still can't get over it being bent symmetrically to 30 degrees with my calibration device and then steering off course to way off center when I finished it by hand.