Hanging a Glass Mirror with a French Cleat

[afikaris09]

I re-purposed a very large glass mirror(51" x 27") by putting a frame on it. I plan to use a french cleat, possibly two but since the mirror is glass there is no way for me to screw the cleat into the back of the mirror, I can only use glue. Anyone have any experiencing in this? Will the adhesive (loctite or liquidnails hold up this large of a mirror? I would say a safe guess on the mirror weight is 40-50 lbs.

[Neal]

Can you somehow tie the cleat into the frame you have built or are building around it?

[poolhound]

I have used liquid nails many times and its very strong. The large plate mirrors in 2 of our bathrooms are just stuick to the drywall in this fashion. There are a few retaining clips but I dont think they do very much.

I am not sure about using LNs for just the cleat. Surface area is the key so I might consider first creating a backer for the mirror in maybe 1/2" ply which can be adhered to the glass with LNs then you can glue/screw the cleat to this. You wouldn't necessarily need to back the whole thing but increasing the surface area for the adhesive from just the 3 ish inches of the cleat would make me feel safer.

[afikaris09]

I think I am going to combine the backer with the cleat, maybe make it 12" wide and span the whole back of the mirror. That would be about 4 sqft. of surface area and if I did two(Top and bottom) it would be 8.5 sqft. Probably more than enough. Ill report back with results if anyone is interested.

"Can you somehow tie the cleat into the frame you have built or are building around it?"

There are 4 holes in the corners of this thing that the frame covered. I thought about screwing through them and into the front frame but I was afraid it would put more stress on the adhesive. I guess if the holes in the mirror magically match up with my studs I could just hang it that way but I doubt my luck is that good. I will check when I get home from work.

Thanks for the help guys.