Bonding Aluminum with Adhesive

[mitchbirddog]

I'm remaking an aircraft hood door, the door is .032" 2024 T3 aluminum, on the leading edge of the door is a 1/2" .016" aluminum doubler. It was spot welded, I don't have the facilities to do that and I'm afraid if I found someone the process might be destructive. I believe the .016" doubler only serves as a rub strip. I would like to use an adhesive to attach it. You can't rivet it as it needs to be flush riveted from both sides (not enough thickness between the two parts). Is there an adhesive to do this?

Thanks,

Mitch

 

[GregLocock]

Any decent grade of epoxy. However, I would use pop rivets to clamp it up while the glue sets, then drill them out or grind off the head and tail.

Spotwelding would be better though.

I must admit I have no experience of 16 thou sheet, we use that to wrap candy!

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[berkshire]

mitchbirddog (Aeronautics)
Use dexter/hysol EA9309na it is a rubber modified epoxy with a high peel strength. As long as the metal is well cleaned prior to joining, it will hold without any "chicken fasteners". Because your doubler is so thin you may need to make a wooden or plastic clamping plate to assemble and cure it, or use a clothes pin or small plastic clamp every inch. You can use Cleco side clamps if you do not mind them getting bunged up with epoxy.
B.E.

 

[SWhit]

I have used EA934 to bond aluminum. With any epoxy surface prep is critical.

 

[Stache]

I have used dexter/hysol EA9309 many many times following the instructions of the repair data. The parts have to be completly clean before applying the hysol. The parts should be clamped up or tack riveted together and let set for at least 24-hours at room temp.

If this is going on an aircaft make sure and have your procedure approved before using it as it is an alteration.

Stache

 

[berkshire]

mitchbirddog (Aeronautics)
Stache (Aeronautics)is right. since although this is a repair, it is also an alteration , in that you are not using the manufacturers original method.
However you should be able to do this on a form 337 with a field aproval. If you can prove to the inspector that it is at least as good as or better than the original.
The inspector may require you to put in at least 4 or 5 fasteners to hold the part in case it does disbond. Double flush 1097 3/32 dia rivets should do it.
Make some test coupons of 1"wide strips 6"long with a 3" tail bent at 90 degrees glued back to back to demonstrate the peel strength of the adhesive. Properly cleaned aluminum should rebend as it is peeled apart indicating the peel strengh of this adhesive.
B.E.