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Mirror Heater/Demister? Answered

Hi, I need some advice on how to wire up a homemade mirror heater or demister. I have an old toaster which I have gutted to get the heating elements. I also have a few old wallwarts to power the thing. Is using these wires the right thing to use as a heat source? It doesn't have to get hot, just slightly warm. What kind of circuitry will I need to warm up the wire? I also got some modelling latex to embed this wires in to make a heating "pad" for the mirror and to insulate it. Is there a better material I can enclose the elements in. Thanks.


Oh my, no...not toaster elements. You need something that requires lower power and is insulated. Many cars have heated electrical defrosters or heated mirrors for defrosting/deicing. They also have thermostat and on-LED indicator, both of which I advise if making one yourself. On a quick search, I was unable to find any other specs on them. But this is the kind of thing you are looking for, not the "electrocuter" you would make with the toaster elements.

Thanks for that. That sounds more sensible. I'll look around for an old car mirror heater.

Oh yes, Kiteman reminded me of a great point. If your socket you plug or wire it into doesn't have a GFCI circuit in it, make sure you create one (ground fault circuit interrupter) especially if this mirror is in the bathroom. Many places require it in the building code. And it is the safe thing to do.

I'm no expert, but I think the toaster elements are overkill. As in not so safe. Sure you can't just rub some raw potato on it to keep it from fogging less?

Raw potato? What kind of Wife Approval Factor is that going to get?! ;-)

Maybe that was a substitute for Rain-X . . . try Rain-X!

. Spit works well, also. This technique is commonly used by skin divers to keep their masks clear.

. If you are going to be using mains power in the bathroom, I highly recommend using a GFI, especially on a DIY project.

Maybe a reptile tank heater pad, stuck to the back of the mirror? They're mains-run, so make sure there's a surge-protector in the circuit.