What is the name of the part that closes off a hub? It keeps the guts inside and allows only the axle to come out of it.
e39m5
This question isn’t very well posed. Can you give more detail? It seems like you are talking about the hub flanges, the discs with the holes in them for the spokes. Is it for a square, tapered axle or Profile or other splined axle?
bearing holders.
Ah. A photo. Excellent. I wish I could tell you what it was. It looks like a bicycle front wheel missing the bearing holders. That inside thread is unfamiliar to me. Jagur, JC, and Mojoe are bigger bicycle gurus than me.
Ahh, wait a minute. Now that Im thinking about it, that part was actually to the hub for cranks, not the wheel. It just happened to fit perfectly in the wheel. I am looking for an identical peice to put on the other side so I can attach some cranks. It was in the same position on the other hub, but had a one piece set of cranks coming out of it. Does that help?
e39m5
??? what the hell is that???
my best guess is its a free wheeling 2 speed kick-back hub or the guts from and old Schwinn freewheeling bottom bracket that was on the Suburban for a few years…
either way, why is is on a unicycle?
eh, its from the crank hub on an old schwinn. Any name for it though?
e39m5
the hub as you say that had the cranks going through it is acually called a “Bottom Bracket”.
anyway, this is very interesting. since that Bottom Bracket peice fits in the hub like that i can see somthing working but how are you going to get the 1 peice cranks to go in there? its just not wide enough like the Bottom Bracket is.
I don’t think you can turn that into a unicycle hub without either welding (the easy way) or maching parts to fit (the hard way. In either case, you will end up with something experimental that may not be very strong. You’d be surprised how much force goes through a unicycle axle/crankset.
Why not just use a unicycle hub? At least it’ll start off clean… 
Unfortunately, I couldn’t get the cranks through the smaller hub. I would need to set up an axle and branch cranks off from it. Otherwise, I dont see why this wouldn’t work. Nobody seems to think it will.
e39m5
On the contrary, everybody else thinks it will work. They all just realize that the cost of making it work is more than the cost of an entire new unicycle.