Check out this heavy-duty cage, built by Redneck Mark. He says the bars are 1-inch square tubes:
Image may be NSFW.
Clik here to view.
Image may be NSFW.
Clik here to view. Image may be NSFW.
Clik here to view. Image may be NSFW.
Clik here to view. Image may be NSFW.
Clik here to view.
Redneck Mark is also the man who built my cage. You can read more about my cage by clicking here.
You can reach Redneck Mark at bootsncamo@yahoo.com, or visit his website, www.communityblacksmith.com.