Cowling fasteners

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DaveD

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I'm surprised this hasn't been discussed before, but maybe my search skills are failing me!

There seems to be quite an array of options, so I'd like to know people's preferences. Dzus, camloc etc. Work well fo aluminium (I'm not a fan of the Dzus spring, so I prefer cam lock style) but what are the alternatives for securing composite cowlings. Composites don't really like rivets, so the "piano hinge with removable wire" looks like quite a nice solution, plus composite hinges are fairly easy to make.

What other options are there?
 

Kyle Boatright

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I've used camloc's, hinges, and screws into nutplates. On long, relatively straight sections, I prefer the hinges. On curved sections, I like screws and nutplates. Camloc's are a lot of $$ for something that is less attractive than screws and only saves a little time in the cowl on/cowl off cycle.

YMMV.
 

DaveD

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I've used camloc's, hinges, and screws into nutplates. On long, relatively straight sections, I prefer the hinges. On curved sections, I like screws and nutplates. Camloc's are a lot of $$ for something that is less attractive than screws and only saves a little time in the cowl on/cowl off cycle.

YMMV.
My only concern with screws is, because I'm working on a pusher, if one did happen to vibrate out it would go through the prop. Other than that I agree, camlocs are rather expensive.
 

Kyle Boatright

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My only concern with screws is, because I'm working on a pusher, if one did happen to vibrate out it would go through the prop. Other than that I agree, camlocs are rather expensive.
My RV-6 has had 26 screws in the cowl for 20 years. 10 across the top, 10 across the bottom, and 6 in the inlets. Haven't lost one yet. Haven't found one that worked loose yet either.
 
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gtae07

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Dad's RV-6 cowl (fiberglass epoxy) uses hinges everywhere except for 6 screws right behind the spinner. He's had a couple rivets pull out on the bottom hinges right next to the exit air opening but otherwise no issues in 19 years and about 1800 hours or so.
 

karmarepair

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The original Dzus are pretty straightforward and idiot-proof. You could even mount the springs with blind rivets if you hate riveting.
I'm a fan too, they don't wear out and get sloppy as quickly or as badly as Camlocks. I think that they are more costly in parts and labor than Camlocks though, which is why generations of Cessnas soldier on with what I consider to be an inferior closure.

It can be a bee-yatch to pull the pins on hinges - the previous builders of my Sonex replaced them with, wait for it, Camlocks <frowning>.
 

TFF

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I don’t like Dzus in lifespan and the tools are pretty expensive unless you want to make your own. The fastener always wears into the sheet metal. The collar type will eat through a panel with the collar and the springs get bent or pop loose. Camlocks take some setup. That is a pain. Figuring out depth with any of quick fasteners is a pain. They are worth it overall. If you got a relatively straight run the hinges are pretty good.

If you are going to pop the cowl off to do a preflight, camlock would be my pick. Dzus second. If it stays on until inspection, hinges. If you don’t want to mess with setups, screws.
 

Daleandee

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I used Southco fasteners on my cowl. Been working well for nearly 10 years.

Other parts of my cowl utilize either piano hinge or machine screws. Never lost a fastener ...
 
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