Gluing metal to wood

Andy:

I would use these

AF 163–2U     3M/Aerospace and Aircraft Maintenance Division 3211 East Chestnut Expressway Springfield, MO 65802

Grade 5 – Green

Andy,

What's your application?  Structural?  Non-structural??  Aircraft or non-aircraft???

Cheers!

Joe

Aircraft and structural. Hinges to the stabilators, torque tubes, wing hinges, rudder hinges, etc.

Looking at the plans, it appears that most of the metal to wood stuff also has bolts.

Andy,

As a chemical engineer who specialized in adhesive bonding, I can tell you that bonding metal to anything is tricky if you are depending on the bond for structure.  There are many variables including the design of the joint, surface preparation, properties of the adhesive itself, curing procedures,  thermal expansion characteristics of the two materials after curing, etc, etc,  Aluminum is particularly tricky--aerospace companies take elaborate precautions to properly prepare aluminum surfaces for bonding and to control the bonding and curing processes.  Aircraft homebuilders do not generally have the knowledge or the means to control all the variables.

I personally would not depend an adhesive bond between metal and wood for anything as critical as a control surface hinge or control system component.

Of course, there are other reasons to apply an adhesive between a metal part and a wooden part.  One good example is to seal the gap between the two to prevent water from being retained in the joint.  Another good example is to "bed" the metal part in place using an adhesive, thus taking up any gap between the two and preventing the joint from loosening or "working" in service.

However, in all these cases, I would want the structural attachment between the metal and the wood to be via bolts or other mechanical means.

Hope this helps!

Mike

Andy, I recommend you go here:

http://www.westsystem.com/ss/bonding-hardware/

and read what West System says about bonding fasteners and hardware to wood. I had a similar problem in my Dalotel's rudder redesign, which required bonding/fastening an angled bracket to the inner plywood of my new spar. Basically you sand the epoxy into the metal with coarse sandpaper, and stick it down to the wood using the properly prepared epoxy. Of course you also MUST use bolts to secure it. Even though my setup loads the metal-to-wood joint only in compression, I have four bolts holding the horn bracket to the rudder spar. See the linked photo. The tailwheel bracket below it is also epoxied and bolted. Hope this helps, and good luck.

..........Ray

Thanks Ray! I'll check it out.

(Thanks for all the other replies too!)