Hi!
For the most part you can use the simple plastic or vinyl (or whatever combination it is). Personally, if I was building just one or two small - medium size cages I'd call local glass shops as most should stock it. You'll need to either buy some beforehand or get a scrap piece from them so you'll know how wide the track is in order to make the frame it will attached to the right width (See Upscale's drawings in his post. Good job, Upscale!
).
Once you get the cage built & track installed, take it to the glass shop and let them measure & cut the glass for you.
For larger cages and cages that use large glass panels you should use the metal track with rollers on the glass. Again, for just a few small - medium cages, see your glass shop.
I just did sliding glass doors on a 7ft long x 3ft wide x 21in high Burmese Python cage. I priced the metal track & rollers from Outwater, compared it to local glass shop price. I paid just a little bit more to get it from my local glass shop, but here's the kicker - the few bucks extra I spent meant I didn't have to do all the calculating, measuring, cutting or installation.
I got a scrap piece of their metal track, build my frame and took the whole cage down to them & let them install it. The opening is 81 inches long x 14 inches high. I got laminated safety glass because they stocked it and I didn't have time to wait for tempered glass to be delivered. Tempered is stronger and even a tad cheaper, but usually a few days wait. My cost was $145. But that's usually above & beyond the typical caging needs of most keepers. That was more than I wanted to spend but by the time I got to that point I had a million other things going on and the ol' noggin' was on system overload. I'll most likely do the exact same thing for the other 7 cages I've got to build.
You can even use a table saw or router to cut your own glass grooves in the cage face. I did that for a Savannah Monitor cage. Just remember that you have to make the top grooves a tad deeper if you want to be able to just lift the glass up & out of the track.
Best wishes!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American

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