carbon fiber cowl fasteners

[larryMar]

Can one simply rivet nut plates, etc to carbon fiber without damage or special precautions?

Thanks

 

[msires]

Not really. If the carbon is touching steel or aluminum you’re setting it up for corrosion.

 

[Dean Pichon]

Can one simply rivet nut plates, etc to carbon fiber without damage or special precautions?

Thanks

The typical technique to prevent galvanic corrosion between carbon fiber composite and metal components (eg. nut plates) is to place a layer of very light fiberglass cloth (aka a "veil") set in epoxy resin at the location of the hardware installation. From there, nut plates can be bonded ("Clickbond" hardware) or riveted. On my RV, I used soft rivets (AN426A) to prevent localized damage to the fiberglass laminate during squeezing or bucking. I don't have any carbon on my -4, but believe soft rivets would still be prudent in this situation.

 

[larryMar]

Thank you,

Do you also dip the soft in epoxy or something to prevent corrosion in them? Can epoxy alone be used to hold the nut plates?

It would have to hold the 2 cowl half's together... I would think that as long as the nut plate stays on to screw into - it would be fine...?...

Thanks again,

 

[Dean Pichon]

At a previous employer, we would install the rivets "wet" by dipping them in an epoxy primer. This is probably over-kill in our situation. If you prime over the completed assembly, I would expect the installation to last several lifetimes.

You can bond nut plates that are designed for this process, like this one:

https://www.sriperformance.com/Clic...TW4p-vN-l5yQgx85KoIObJy9cEOnjgRBoCc-wQAvD_BwE

The K1000-type nut plates must be riveted.

 

[PhatRV]

My Sensenich spinner backplate is carbon fiber and Sensenich installed the nutplates using pull-rivets. I think the rivets are stainless steel. I think every ground adjustable Sensenich carbon fiber propeller that was sold through Vans have these nutplates.

 

[wirejock]

Carbin fiber and fasteners

My cowl isn't carbon fiber but there us a strip around the perimeter and the plenum has a layer. Carbon fiber is encapsulated with fiberglass or a layer of epoxy before fasterners. Skybolts and nutplates.