Spool holder that's longer and slimmer than the original one to hold different spools
Since Makerbot was out of black white abs, right when I needed more, I ended up ordering spools off of Amazon. The ABS is fine, but the spool that it came on were a different size and wouldn't fit on the holders that came with my makerbot. So I took the one off the back of my makerbot and modeled myself a copy, but with a holder that's longer to hold the spool, and slim enough for the spool to actually get on it.
It's a little over 3.5in long and an inch and a half in diameter.
I've got two versions here - one has the whole holder as a single piece, but you'd have to print with raft support (I haven't tried it that way yet). The other is in 2 pieces so it could be printed without any raft, but you have to glue them together. I used this really awesome superglue that basically melts the abs together, and there's been no indication at all that it might give or break so far, and I've been printing on it for a while now.