I am trying to attach a large steel handle to the aluminum frame of a sliding glass door – see picture. As you can see in the drawing, the handle will mount to the door frame at two 4″x 4″ plates. I am looking for a permanent installation. Both the handle and door would be powder coated. Should we rough up the finish or sand it off for better adhesion? I am guessing that it takes less than 8 pounds of pressure to slide the door open and closed. Is there a 3M tape that would permanently bond this handle to the door?
Thanks for the question. Unfortunately, it looks like the picture did not come through. Can you try to share it again in the comments below? I’ll give some general thoughts now and update with additional detail if you are able to share the image.
My first thought when I hear “handles” is “peel stress.” Shear and tensile modes evenly stress the bond, but peel modes concentrate stress at one end. While we have guidelines for designing in shear and tensile, joints with peel modes tend to require more testing to ensure the stress is adequately managed.
One way to manage peel stresses is to create a large bond area that puts more of the stress in the shear plane, and it sounds like that may be part of your design. If the 4″ x 4″ plates direct most of the stress into the shear plane as you are sliding the door, then that might work depending on the geometry of the handle and the way the stress is applied.
There are two-part structural adhesives that could be considered (comment below if you’d like more details), but if you want to test a tape, I suggest 3M™ VHB™ Tape 4941. Powder coated paints typically have low surface energy flow agents that make bonding difficult, so I would test tape primers 3M™ VHB™ Tape Universal Primer UV or 3M™ Tape Primer 94. Abrasion is probably not needed unless there is very heavy texture that reduces tape contact with the surfaces.
Data sheets are below. Let me know if you have more questions.