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Will flexwatt heat tape melt or deform an 1/8" plexiglass frame being used as the bottom of a cage? The heat tape will probably be running at around 90-95F as it is heating a ball python cage. All advice or oppinions are apreciated.
Thanks, STeve

It may.

The rule with heat tape is to give it room to breathe -- NEVER sandwich it in between two hard surfaces as the heat is trapped and continually builds up to dangerous levels.

If there is about 1/2=inch of space either over or below the heat tape and you monitor the temp on the hot spot with a probe and control it to 90-95 with a rheostat there shouldn't be a problem.

Just FYI, once I had a rheostat fail -- it was one of the rotary type wall switch rheostats. Luckily it failed in the low position so the hot spot went cool.

I stopped using those rheostats and went with lamp dimmers (the one made by Lutron is good and you can get that at Home Depot).

Just make sure there is breathing room either above or below the heat tape and you monitor the temp right on the hot spot.

Bill

I have an extra thermostat I can hook it up to. I'll rout a half inch groove for the tape to fit into.
Thanks again,
Steve

An important factor to consider is the insulative properties of whatever is around the heat tape. Plexiglass is a good insulator and so heat will have a much tougher time getting through it than it would getting through say glass. You may discover that your heat tape does a great job of heating the air under your tank, and a lousy job of heating the plexi bottom.

You should do a test if possible. I would feel fine taping (with heat resistant tape) the heat tape to the bottom (outside) of your tank, and leaving 1/4" or more of air space below the tank. That may not heat the inside of your tank enough, so test it to see.

The point at which plexiglas starts to get soft is around 250 degrees (F) and even if your plexi is a good insulator, if it is 240 degress on one side of your 1/8" plexi, it is WAY to hot for your snake on the other side. My point is that if the heat tape isn't hot enough you can experiment with sandwiching it on the bottom with different materials, to allow a little heat buildup. Just don't let it get above 250 degrees. (water boils at 212, just for reference)

A worst case situation would be to sandwich your heat tape between your 1/8" plexi, and say fiberglass attic insulation. That is going to max out the trapped heat, and my guess is that it still wouldn't pass 250, unless you had a good insulator on the other side of the plexi too (like sand).

The bottom line is that, in the normal configuration (heat tape on bottom of tank with an air space below it) you probably have to worry more about the heat tape not being able to heat your tank enough, than you do about it getting too hot.

I suggest that you experiment with it. If it isn't heating your cage enough, try sandwiching it with a piece of 1/8" plexi on each side and see if it starts getting too hot to touch. If so, try a worse insulator, like glass, or stone tile. If it doesn't get hot enough, try better insulators like a piece of wool blanket or styrofoam (be careful here, it it is at all possible to get too hot, it will happen with the styrofoam.

good luck