Plastic Fairing Repair Question

[Jeff_S]

I was creeping along under my J the other day just looking for anamolies, and I saw that one of the "rounded triangular" plastic fairings that extends off the wheel well was cracked. It has been this way for awhile, obviously, because other people had stop-drilled the crack. But I'd like to do something of a more permanent repair, besides duct tape! (Also, the part is riveted on, so I REALLY don't want to consider replacement!)

Is there any reason a good epoxy wouldn't work? Or maybe just some super glue? My concern with the super glue is that I suspect the edges have debris and residue in them that wouldn't allow a perfect mating of the plastic, whereas an epoxy would fill that in better.

This is probably much ado about nothing but I've learned that with airplanes there is often some reason an obvious solution may not be recommended...so I thought I'd float it out there.

Thanks!

[74657]

Mine are cracked as well and being held together with foil tape (previous owner's fix).  My plan is to get them back in decent order with fiberglass when we re-paint the plane this winter.  I have had good luck repairing plastic with 5 minute epoxy and sanding smooth after it sets up (and even laminating it with fiberglass if the gap is really big).  Superglue is typically too thin and runs when trying to fill big gaps. 

[RJBrown]

Super Glue (cyanoacrylate) are way to brittle for this use and would contaminate the area for a good repair. Epoxy / fiberglass cloth is a good way to fix them. Removing and repairing from the inside would look much better than trying to finish from the outside.

[Piloto]

These fairings are typically cracked by the inboard door when the gear retracts. This happens when the cushion donuts are partially worn or compressed and causes the door to rub against the fairing. To prevent from cracking again after repair make sure the donuts are in good shape.

Repairing of the fairings is best done by overlying a fiberglass cloth over the damaged area and then sanding it off for smoothness.

José

 

[KSMooniac]

Those fairings are just pop-riveted on, so it is fairly trivial to remove and re-install if you want to really repair them correctly/permanently.  Just carefully drill out the pop rivets and you'll have it off the plane in less than 5-10 minutes.

[thinwing]

for repairs of this type..I recomend hysol...an aerospace 2 part epoxy that is thixotropic...it wont run and though it takes 24hrs to set is really tough stuff...use regular masking tape to make a former...apply good layer of hysol with or without glass cloth..than peel tape and finsh with a dremmel sanding disk...makes a good perment repair...kpc

[jetdriven]

I believe that fairing is a UREM urethane piece, just like the plastic bumpers on your car.  Fiberglass, epoxy, super glue, etc are all going to fail because they cannot bond properly and are not flexible enough.    you need a urethane repair kit for a plastic car bumper.  Here is a sample of repair kits, there are others on the web.  I would also drill the pop rivets and repair it off the plane.  You can repaint the fairing to match with a touch up kit from Awlgrip.  Its a LPU paint just like Imron.  Done right the repair is invisible, strong as new, and relatively cheap to do.

[laytonl]

The fairings are not too terribly expensive.  I just drilled my out and replaced them.  Probably less than an hour per side to do.  Lee

[Jeff_S]

Thanks to all for the suggestions...I knew I'd learn a thing or two! Being a self-admitted non-wrench monkey I assumed rivets were a big deal, but now I know the ease of pop rivets. I still believe for the size of my problem I'll try some epoxy first and see if that holds, but if not, removal and repair or replacement doesn't seem like a big deal.  Cheers!