Cowl Fasteners

[Andy Walker]

Hey all...

I had a conversation with Kip a few weeks ago about cowl fasteners for the upper edge (that mates to the firewall). The factory-supplied fasteners are a little on the chintzy side. Kip used floating nut plates on his Waiex, which makes aligning the screws for the canopy much easier, plus I think he said he used more fasteners than the plans called for, to reduce bowing of the cowl fiberglass.

I decided to go a little different direction, and just ordered some "CamLoc" fasteners from ACS. It's a flush mount anchor plate and a metal stud sheath with a spring loaded locking pin inside. Here's the CamLoc stud:

http://www.aircraftspruce.com/catalog/hapages/camloc2700.php

and the anchor:

http://www.aircraftspruce.com/catalog/hapages/receptacle.php

They are pricey, I got ten studs and ten anchors, and I think it cost about $6.60 for each set (yep, $66 in fasteners, gulp!), but I think they are a great balance of convenience and security. I like that the stud is retained and can't fall out and get lost, and you can just unfasten them with a 90 degree turn of a screwdriver. For stud length I selected 2700-4 (0.120 to 0.149 total grip thickness). this is based on the 0.125" cowl thickness and the firewall and upper bow. These might be a little short, I'll try them and exchange them for longer ones if they don't work out.

[N111YX]

That will be a nice touch, Andy.

I may have used the plan-callout number of fasteners on the cowl. However, I know for sure that I added a few on the windshield as that it what has a tendency to bow...

[radfordc]

Having fought the Southco fasteners for some years I finally converted to what I consider to be the ideal fastener.... 10-32 machine screws and nut plates. This is what I use both on the cowl and the windshield. You should double the number of screws in the front of the windshield...if not the Lexan will bow up significantly.