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Gluing metal to wood

Posted By:
Andy Gamache
Homebuilder or Craftsman
122
Posts
28
#1 Posted: 4/8/2010 03:55:11

Will T-88 work for bonding metal to wood? Or is there another glue on the market that I should consider?



Joanne Palmer
Young Eagles Pilot or VolunteerHomebuilder or Craftsman
276
Posts
68
#2 Posted: 4/8/2010 10:14:32

 

Andy:

 

I would use these

AF 1632U     3M/Aerospace and Aircraft Maintenance Division 3211 East Chestnut Expressway Springfield, MO 65802

Grade 5 Green

 

or

EA9696U      Henkel Corporation Aerospace Group  2850 Willow Pass Road Bay Point, CA 94565

Grade 5 Green

 

These are 4200psi (ultimate shear) systems so plan accordingly.  You want the bondline as THIN as possible with no voids.

 

 

 

 

 

 

 

 



Joe Norris
Vintage Aircraft Association MemberYoung Eagles Pilot or VolunteerHomebuilder or CraftsmanAirVenture Volunteer
328
Posts
137
#3 Posted: 4/8/2010 10:19:34

Andy,

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

Cheers!

Joe



Lasciate ogne speranza, voi ch'intrate
Andy Gamache
Homebuilder or Craftsman
122
Posts
28
#4 Posted: 4/8/2010 19:27:48
Joe Norris wrote:

 

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.



Brandon Kunicki
Warbirds of America Member
1
Post
0
#5 Posted: 4/8/2010 20:41:25
AF 163 is a film adhesive. Normally is is cured in an autoclave at 250 degrees F. Not sure how well that works on wood...
EA9396 is primarily a laminating resin. It is a thin (liquid) epoxy compound. EA9396 is a thick (filled) paste adhesive and might be more suitable.
In any case you should contact the manufacturer and describe what you are planning to do. You might want to grit blast the aluminum, followed by etching and priming with an adhesion promoter for best results. I would hate to see your control surface depart the aircraft due to a bond failure.
If this is truly a bolted connection (which I suspect it should be), using T-88 as a faying surface sealant or gap filler is probably adequate.
Joanne Palmer wrote:

I would use these

AF 1632U     3M/Aerospace and Aircraft Maintenance Division 3211 East Chestnut Expressway Springfield, MO 65802

Grade 5 Green

 

or

EA9696U      Henkel Corporation Aerospace Group  2850 Willow Pass Road Bay Point, CA 94565

Grade 5 Green

 

 

These are 4200psi (ultimate shear) systems so plan accordingly.  You want the bondline as THIN as possible with no voids.

 

 

 

 

 

 

 

 

 

 

 

 

 

 



Mike Huffman
Homebuilder or Craftsman
11
Posts
4
#6 Posted: 4/8/2010 21:05:39

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



G. Michael Huffman SportAviationSpecialties dot com 904-206-0522
Ray Ordorica
Homebuilder or Craftsman
36
Posts
1
#7 Posted: 4/12/2010 02:22:51

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



Files Attachment(s):
Horn bracket DSC_6451.JPG (713871 bytes)
RayO
Andy Gamache
Homebuilder or Craftsman
122
Posts
28
#8 Posted: 4/15/2010 22:01:26

Thanks Ray! I'll check it out.

 

 

(Thanks for all the other replies too!)