Nyloc nut on eyebolt: How tight?

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ActingLikeAKid

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Putting in an eyebolt on an HPR rocket. I'm using a nyloc nut so it won't back off. It occurred to me that if I leave it a tiny bit loose, that will let the eyebolt spin freely during recovery, which should reduce twisting in the gear. Any reason not to do this? Or should I snug it down securely?
 

JJSR

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It would depend on where your putting it.
But I would think where ever you put it ,centering ring, av bay, it would eventually start to brake through it from all the load jerks it will get
 

Kruegon

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I use the same on my builds. I usually tighten it down. Any slack could cause the bolt to snatch at the connection point. Almost like jerking the head of a hammer against something. Snug with reasonably wide washers will reduce the strain that a loose bolt impact would cause.
 

Banzai88

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Also, you don't want a working joint of hard parts down deep in the airframe. That purpose is best served with a swivel.
 

Nathan

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Also, you don't want a working joint of hard parts down deep in the airframe. That purpose is best served with a swivel.
Exactly what I was going to say but you beat me to it.
 

ActingLikeAKid

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Well, that answers that pretty unequivocally :)

Next question: The eyebolt is load-rated (500, I think?) and the threaded part is about 2" long. I need less than half of that. I'm thinking
-If I cut it, I'll need to clean up the threads a little, but it would save me a bit of weight. Don't think it would hurt anything
-If I leave it as is, I'm sending an extra few grams up. I'm leaning toward leaving it alone. Thoughts?
 

rharshberger

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Trim the length, if its longer than the nut you are not gaining any strength, and as you pointed out the extra length is just extra weight.
 

Nathan

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I do that with bolts and threaded rods all the time. Bolt cutter will mash the threads a little so just remove about another 1 mm with a file until you get to good threads.
 

Dave A

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Use large fender washer under the nyloc nut anyway, if loose it can't pull out. Otherwise use a swivel on your recovery equipment.
 

Jarhead

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Awesome. Thanks, y'all. Now, if I could just find my !#@!~$ hacksaw....
Before I cut I always run a standard nut on past the cut line. After cleaning the threads with a file removing the nut chases the threads for me.
Little something my dad taught me....
 

ActingLikeAKid

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Before I cut I always run a standard nut on past the cut line. After cleaning the threads with a file removing the nut chases the threads for me.
Little something my dad taught me....
Thanks for the reminder. One of those "I used to know that...." things :)
 

dmgrime

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So simple I love it! Ended up using a die to rethread my all rod. Doing this from now on! Thanks!
 
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