Still new and nuts on nuts

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jeffreyK
Posts: 43
Joined: Wed Jan 15, 2020 9:41 pm

Still new and nuts on nuts

Post by jeffreyK »

I am starting to order bolts and nuts for the wing. I have seen locknuts on many homebuilts including the Piet on display at OSH last year. In the wing it would seem castle nuts and pins would be a better choice for control cable and cable stay hardware where fabric will be covering the hardware and I won't be able to tighten or adjust the bolts after the wing is done without cutting fabric. I appreciate these bolts are perpendicular to the force on the fitting but there is all that vibration. I may be overthinking this but any thoughts?
Earl Brown
Posts: 69
Joined: Mon Nov 04, 2019 12:24 pm

Re: Still new and nuts on nuts

Post by Earl Brown »

If the parts you are talking about are not rotating, then nylock or metal lock nits will work.
It would also be a good idea to add inspection panels or plates where you can so you can get to the parts and inspect them.
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taildrags
Posts: 637
Joined: Tue Mar 07, 2017 10:39 pm

Re: Still new and nuts on nuts

Post by taildrags »

Not saying that my airplane is the example that all should follow, but someone asked me about inspection covers on the underside of the wing on 41CC so I took pix and put it on a little webpage, here-

http://www.flysquirrel.net/piets/repair ... ction.html

Oscar Zuniga
Medford, OR
Air Camper NX41CC, A75 power
jeffreyK
Posts: 43
Joined: Wed Jan 15, 2020 9:41 pm

Re: Still new and nuts on nuts

Post by jeffreyK »

Thanks for the tips. I do plan on inspection panels however would not want to put one at every bracket site. Several strategically placed would allow inspection throughout the wing visually and with the flexible scopes now available. I recently helped restore an L-3 for the D-Day museum and there were not that many inspection panels. I'm guessing they were good with mirrors or peeked in before patching bullet holes!
Jeffrey Kornblum
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taildrags
Posts: 637
Joined: Tue Mar 07, 2017 10:39 pm

Re: Still new and nuts on nuts

Post by taildrags »

Jeffrey; I have an inspection "borescope" camera too (Harbor Freight), but it doesn't do any good for getting in there to lubricate pulleys. And I didn't build my airplane... it came with all those inspection covers when I got it. My A&P loves them though.

-Oscar
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Clay Hammond
Posts: 40
Joined: Thu Feb 23, 2017 11:46 am

Re: Still new and nuts on nuts

Post by Clay Hammond »

Don't use photos of antiques or original fabric as a guide for inspection holes in modern day covering systems. Way way back the cotton covering wasn't expected to last...fungus, mold, UV and weather all took a harder toll on cotton than they do on synthetic coverings nowadays. That and not everyone had a Hangar to store in. Airplanes back then were covered more often and inspected internally that way, leading to less access points while covered...that and the inspection best practices were not as stringent as they are today. You want to be able to lubricate anything that needs lubricating, see as much of the internal structure as possible, and see anything directly and positively that needs specific attention at inspection time.
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KenBickers
Posts: 128
Joined: Tue Mar 07, 2017 7:00 pm

Re: Still new and nuts on nuts

Post by KenBickers »

You'll want inspection holes for places that need to be lubed or inspected annually. You may also want to glue in, during your original covering job, inspection rings and doilies in several places that might need to be opened for a future repair. For example, my pitot tube goes through the leading edge of my left wing. I don't need to look at the back side of the pitot tube each year during the condition inspection. Should I ever need to replace the tube or check the attachment where the tube connects to the flexible line, then I could cut out the hole. Better to glue those rings in now, even if you don't open them up for many years, or ever. Cheers, Ken
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