>>Would the plastic track suffice for a small cage (opening is 14inches high, 40 long...wierd, i know)
Yes
>>If so, how tall would the glass need to be to fit after the track has been mounted?
It depends on the dimensions, I mount the track then measure for the glass that way there is no mistakes.
I would give you a guess but the track I use may be different from the track you use. Usually adding the heigth of both tracks subtracting that from the opening heigth and adding a 1/2" works but I can't say for sure.
>>On an unrelated note, I got to thinking today. I saw a few unfinish cabinets/bookshelves in Lowes, and envisioned added glass doors and heat to make a professional looking cage.
Sounds like an interesting idea.
>>Anyone given this a shot? How'd it work out? The only problem I could see is that biggest depth I could find was 13inches, which probably would not suffice for the ball and corn that I have.
I have not tried it yet, nor have I heard from any who have. My one concern would be sealing the wood adding substrate dams and adding glass track. Well not a concern really just a important step.
For heat you could use some PVCX to make a space in the bottom of the shelf for heat tape with a whole sheet covering the tape itself. Then add the substrate dams and silcon the lower edges of course I would recommend sealing the wood before that entire process.
Chris Harper can give some good info on sealing the wood, I would give some recommendations but he is far more knowledgable.
My 2 Cents
Jeremy
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"I am become death, the destroyer of worlds" July 16, 1945 Robert Oppenheimer
1.1 Hypomelenistic Red Tailed Boas
2.0 Double Het Stripe Albino Red Tailed Boas
0.1 Suriname Red Tailed Boa
0.1 Anerthrystic Red Tailed Boa
1.0 Ball Python
1.1 Rhinoceros Iguana's
1.0 Green Iguana
1.1 Cream Golden Retrieviers
0.3 Catus Terribilis
0.1 Spouse