How to fix a broken spoke in your fans
Spokes of the fans often break and even if you weld it back it will break even faster again. Here is the method that I use for a quick and cheap fix!
Broken fire fan:
Find a piece of wire similar to that used for the fan and a bit softer. Bend the wire but less than really required (to crate some strain after fixing).
Attach to the fan using tape as shown in the photo. If attached well, the frame will only become stronger.
It could actually be nicer than in the photo, but you got the idea. In my experience the tape does not suffer a lot from the fire, but make sure to check its state from time to time.