Bathroom Mirror

[antman]

Hi all,
My inlaws have asked me to make a mirror for their new bathroom out of some (very) old cedar. I am wondering what the best join method would be for the corners as the mirror will be exposed to lots of moisture and temp. changes etc. Once dressed I think the timber will be around 20mm thick.
Also, what adhesive would be best for the joints? I had thought an epoxy resin of some kind as it would stand up to the moisture better.
My main concern is moisture.
Any suggestions or things to avoid?
Thanks in advance
Anthony

[Fantapantz]

In 'Theory' if its old timber the only seasoning that will occur will be atmospheric, so once constructed the timber should stay stable "if" its sealed well.

"If" its sealed well you could even glue it with PVA (although I wouldn't do it personally). Just make sure you seal the entire project not just the visual parts.

As for joints, its an aesthetic thing, Mitres or Butts its up to you, both I would dowel or biscuit.

[kenmil]

What is all this talk of moisture ? Don't they have an exhaust fan ?

[Fantapantz]

Ever seen a mirror fog up? I don't mean when your kissing the person on the other side!:D

[kenmil]

Mirrors do not fog up when you turn on the exhaust fan.

[antman]

Unfortunate but true. They do have an exhaust fan but being in sunny Armidale NSW, there is not always mirror fogging due to the temp but more condensation whent he shower door is opened. But that aside, if not PVC, what would be the suggested adhesive?

Cheers,
Anthony

[kenmil]

Anthony,

Now that I think about it, I made a mirror when I renovated one of our bathrooms about 5 years ago, and I used liquid nails on the joints. (It is fixed to the wall with liquid nails too) I just gave them a good check and they are holding up fine. Not sure of the composition of liquid nails, but it sure as hells sticks.

[Fantapantz]

If everyone that uses the bathroom uses the exhaust fan all the time? In winter that's doubtful unless they have one with heating lamps.

Personally I'd use Epoxy Resin/Araldyte. If you wanted to use a Formaldehyde you could but they tend to be a bit more expensive. If you do choose a Formaldehyde a Melamine or Resorcinol would be preferable to Urea cause there more waterproof.

[Shane Watson]

If your main concern is adhesive. Check out AV Syntec's Web Site (http://www.avsyntec.com.au) for info. Personally I wouldn't go past AV203.

AS for exhaust fans, I have one but have only used it like once in the past 3mths.

[kenmil]

Do you use a towel before you get dressed ?
Do you turn off the lights when finished ?
Do you turn off the taps ?

Why would anyone have an exhaust fan and not use it ?
:confused:

[Marc]

Ha ha, fan or no fan, one cannot argue that the bathroom is more humid than anywhere else in the house, except perhaps the kitchen when mama is cooking Irish stew.

I think the question was what kind of joints for a mirror frame in such environment.
You don't say the size of the mirror or the thickness of the glass. A good quality mirror can be rather heavy so my personal choice would be to build a frame that looks different from the ordinary picture frame mitred at 45degree.

How would you like a frame were the vertical sides are a bit longer 10 to 25 mm according to taste, and the horizontal butt into the verticals with a mortise and tenon joint? (You could even make the horizontal sides a bit thinner so that there is a step between the two at the front side.

You can Reuter the rebate in the back to have your mirror sitting snug in the cavity, after squaring the corners. You then glue the mirror with a moderate amount of clear silicone, nail a thin strip of timber over the joint all around it (watch to stay well clear of the glass with the nails) and as for the glue problem, I can tell you that such frame would stay in place even without glue at all, for the next 100 years never using a fan since it is the glass and the silicone that holds it all in place.

Still, do glue the thing properly. From the glues suggested, AV203 is perhaps the best choice, but if you build the frame this way, you will be Ok with the Sellies Acquadhere Tradesman choice (green label) I built a spiral stair 14 steps with a central column built like a barrel with 14 sides and a laminated handrail out of 15 x 6mm strips using just Tradesman Choice, and after 3 years it still does not squeak, and you can hardly see the joints even though it is entirley built from recicled oregon. I think Tradsman choice is good stuff.

[antman]

Thank you all! I have started the mirror and as it turns out, the upright sides will be thinner than the horizontal sides so I will use a mortice and tennon rather than a mitred joint. The cedar is magnificent, I just hope that I can do it justice now...

And finally, Ken, when have you known SWMBO to turn a light off when finished? :D

Thanks again!
Anthony

[antman]

Thank you all! I have started the mirror and as it turns out, the upright sides will be thinner than the horizontal sides so I will use a mortice and tennon rather than a mitred joint. The cedar is magnificent, I just hope that I can do it justice now...

And finally, Ken, when have you known SWMBO to turn a light off when finished? :D

Thanks again!
Anthony