Large mirror frame design

[OneStaple]

Hey all,

I just picked up some nice curly maple (see pic) to build a mirror frame for our master bathroom renovation. The picture of the bathroom shows the space above the vanity where it will hang. I plan for it to fill the space, going within 1" of the wall/cabinet on the sides, close to the lights, and about 1" above the outlets at the bottom. So it'll be about 40" tall and 64" wide

The curly maple I found is 4/4, and I plan on making the frame about 3.5" wide. I've read a bunch of threads with suggestions on how to make the frame, but wanted a little feedback on this one.

I plan on doing a mortice and tenon frame (matches our Shaker cabinets). I'll rabbet the back to accept the 1/4" thick mirror (and finish anywhere that reflections might show). I also plan on rabbetting the frame so I can attach 1/4" ply for strength/stability.

I can use thicker ply (3/8" or 1/2"), in which case it will end up proud of the back of the frame. This would push the frame 1/8" to 1/4" away from the wall, which I imagine would be fine since it'll be tough to see the edges anyway.

For attaching the frame to the wall, I'm debating between keyhole slots and a french cleat. The keyhole slots have the benefit of keeping the frame close to the wall, whereas the french cleat does not. But the french cleat concept seems a little nicer.

Questions:
-Is the 1/4" ply thick enough, or would you go with 3/8" or 1/2"?
-Would you adhere the mirror to the ply, and if so, with what?
-Would you use french cleats or keyhole slots?
-If a french cleat, is 1/2" thick wood adequate? It would make the mirror sit 1/2" off the wall. And yes, I'd have to use spacers at the bottom.
-If keyhole slots, verticle or horizontal?

Thanks,
Tyler

[jppierson]

Its gonna be a heavy bugger! My advice would be french cleat, not only is it stronger but easier to level. Perhaps a modified backing that is the same thickness as the cleat system (e.g., two backs with a gap large enough to hang?) would resolve the mirror sitting proud.

[jteneyck]

I made a mirror frame about 3' high and 4' wide, using simple loose tenon joinery.



The 1/4" mirror sits in a rabbet in the back of the frame. The rabbet is about 3/8" deep so there would be less chance of the mirror bridging on the wall. There's no plywood behind the mirror. I don't see any need for that with 1/4" mirror, and it's already plenty heavy.

The mirror is held into the frame with 3M 1/2" wide mirror tape. You can buy it at your local mirror/glass shop. It has hellacious grab on the mirror. You also don't have to finish the rabbet because the mirror tape is opaque.

I used keyhole slots to hang the mirror, in both the top and bottom rail. I wanted it to fit tight to the wall. It's not going anywhere.

John

[JGrout]

no ply glue the mirror to the wall and apply the frame to the mirror.

no need to make the frame carry the weight of a semi permanent fixture

Joe

[jteneyck]

That's how my previous mirror was installed, and by a high end mirror shop. After about 10 or 12 years I could see round spots in the mirror where the adhesive changed the color of the mirror backing. I've seen the same issue in some hotel mirrors, too. And when I decided to get rid of the mirror I had to cut/break it off the wall to remove it. That wasn't fun, and then I had to repair the damage done to the drywall. That was no fun either. So when I designed the new mirror and frame I made sure not to use that approach.

I used keyholes in both the top and bottom rail and beefy screws in the studs to hang my mirror, but there are other flush mount options, including interlocking metal clips and even a recessed French cleat.

John

[JGrout]

Quote:

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After about 10 or 12 years I could see round spots in the mirror where the adhesive changed the color of the mirror backing

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they used the wrong adhesive

[OneStaple]

For what it's worth (and before an argument breaks out), I'm not excited about the idea of gluing the mirror to the wall. I know there are right and wrong adhesives and all that. If I were building the frame around a mounted mirror, I'd probably hold it on the wall with clips. But that's just my preference.

I've been thinking through french cleats and am having trouble with figuring out how to do a recessed french cleat nicely, especially starting with 4/4 wood with a mirror rabbetted in. How much of a "hook" do I need on the cleat? 1/2" or so?

Thanks,
Tyler

[JGrout]

no fight here just the facts

and the fact is your mirror is going to be heavy

French cleat thickness would be 1/4 " minimum width, 1 1/2" and at least 75% the length of the top member IME

It is obvious you have not worked out the logistics for the in frame cut.

The way I do them is to dado out the recess (I stop mine but you can fill in the ends with fillers after. I make the closed bevel cut with the bit shown below





I have not attempted to do a frame with a mirror as heavy as yours so you are on your own if you choose this direction

You could also make the miter on the TS and make it slightly thicker ( say 3/8" ) but it will have a thickness of the blade flat top. That is OK as long as the cleat fully engages before it bottoms out. If you go this way cut off the point of the wall cleat so it is slightly wider than your sawblade

Joe

[Bill Holt]

I did a mirror frame similar in size. Our son wanted the mirror to tilt slightly so he went for the wire method. As for the French cleat, I/2" wood seems iffy to me. I used commercial aluminum French cleats (they were free) for my shop cabinets. Each cabinet is 51"wide, 48"tall and 5" deep. The doors and backs are loaded with tools. All that to say, they are much heavier than your mirror and the cleats require less than I/4" when installed.

[jteneyck]

Take a look at these wall panel hanging systems, and specifically these. There are other systems, too, but all use the same principle. They hang sheets of MDF on the wall with these systems. It's the same idea as using a French cleat, just less work.

If you want to use a French cleat system, I would think about using 1/2" aluminum bar stock for the wall cleat instead of wood.

John

Joe, you might be right; it might have been the wrong adhesive despite that it was a pro glass shop that's been in business for more than 50 years. All that proves is that it can and does happen. Then there was still the problem of getting the mirror off the wall and repairing the damage afterwards.

John