Is it acceptable? I understand it may be sloppy but...
Shear.Any heat involved?
No
In tension or shear?
So long as the drilled hole is not in the grip portion of the nut. 43.13 as something on this, that is more exactly stated.No issue at all using self locking nuts on a drilled bolt.
Can you point to the exact section of AC43.13 that states this Gordon?So long as the drilled hole is not in the grip portion of the nut. 43.13 as something on this, that is more exactly stated.
Well, I may have egg on my face. I can't seem to find a pertinent reference. I know I've read that stipulation somewhere - maybe not 43.13. Seems section 7-34 and following sections would apply. Anybody able to help clarify this?Can you point to the exact section of AC43.13 that states this Gordon?
Yeah I can clarify it. It’s standard practice to use a bolt with a drilled shank and a self locking nut if a bolt without a drilled shank isn’t available. As Mike pointed out it’s slightly more expensive. But it moves things along.Well, I may have egg on my face. I can't seem to find a pertinent reference. I know I've read that stipulation somewhere - maybe not 43.13. Seems section 7-34 and following sections would apply. Anybody able to help clarify this?
Agree. How can it possibly be wrong? But it still bugs me to find an official reference. Arlington and Toledo aren't that terribly distant - we should touch base one of these days.Yeah I can clarify it. It’s standard practice to use a bolt with a drilled shank and a self locking nut if a bolt without a drilled shank isn’t available. As Mike pointed out it’s slightly more expensive. But it moves things along.
Charlie
A&P/IA
"Here is another reminder about self-locking fiber nuts (reminders are sort of rules, too). Do not make a habit of using a self-locking fiber insert type of nut on a drilled bolt smaller than 5/16" in diameter. If you do use a drilled bolt, be sure that there are no burrs around the cotter pin hole that could tear into the elastic insert. Maybe they make too much of this rule but then again, who wants to drive around with slashed tires even if they do hold air?"Well, I may have egg on my face. I can't seem to find a pertinent reference. I know I've read that stipulation somewhere - maybe not 43.13. Seems section 7-34 and following sections would apply. Anybody able to help clarify this?
If you do use a drilled bolt, be sure that there are no burrs around the cotter pin hole that could tear into the elastic insert.
I think we were both at the aviation trade show in Puyallup a few years ago. I ran into Eric there but didn’t see you. Stop by my hangar in Arlington sometime and check out my project. I am right next to the Castle & Cooke gas pump.Agree. How can it possibly be wrong? But it still bugs me to find an official reference. Arlington and Toledo aren't that terribly distant - we should touch base one of these days.
I too have seen that, but generally consider the bolt was too short for the application. As long as the cotter pin hole is outside of the threads of the nut even though inside the elastic stop, the bolt should not break.Piper did it when they moved from castle nuts to self locking nuts. After seeing some bolts in tension fail at the cotter pin hole I make sure I don't do it.
I don't remember the application, many years ago on a warbird. I have a good collection of hardware so try and use the corresponding bolt to match the nut.
Today while torquing one of the three 1/4" drilled bolts between the two crankcase halves at the oil sump that get safety wired together.
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