There's no danger in using pine for your cage. Protecting the wood from the elements can be as easy as painting it, covering with Contact Paper, vinyl flooring, and/or polyurethane. I think you'd get the most protection from fiberglass resin or other two-part epoxies.
The epoxies have a learning curve & can be a pain to install until you get it figured out.
If you can, I suggest making the cage size 6ft long X 2.5ft wide X 1.5ft high. In other words - take 6 inches off the height and add it to the width for a more useful size cage.
Have fun and be sure to post your results!
Later!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American
