I was looking at all the cages in the Massive Cage Thread and saw a couple homemade ones that were made from mesh or grid squares. Where did you find such a thing? I have square grids but the spacing is huge compared to what a rat cage would need (I've let me girls climb on it and they can easily pass through). I hate the cage I have right now because there is only 1 door and I have to use the top of the cage as a door, which isn't really supposed to be done. It's a big, converted bird cage - not really what I want for my rats. Anyone know where to find these square grids? Or have other (cheap) ideas similar? (anyone have an extra cage they don't want in Michigan? - semi-serious)

any hardware store

I have made several cages out of hardware cloth (the actual name of it).  I got it at Home Depot.  I have modeled the R-680 and have made a couple smaller cages as well.  Many people are using the hardware cloth to make their ferret nations escape-proof.

They have them at my Target, too.

I think I'm going to stick with the cubes I have and cover them with wire mesh myself, if I decide to make a cage out of the cubes at all. I was planning on it, but nothing I do seems to be working in the space I want it to fit. Thanks for the info, tho! At least I know where to get more of them if I need to.

It's not so much the corners of the panels, but the actually wire spacing of the grids. They're more than 1" x 1" and my rats seriously have next to no problem walking through them. I'd still have to cover it for that reason or they'd be completely free-range ratties. lol