As you work with more fans, it's undoubtable that you will come across some fans that have been absolutely butchered by kind-hearted souls of its past history. What does this mean? Basically that you're going to have to do undo a lot of other peoples work. Never kid yourself into believing that any fan you own is 100% "original." Considering these are work-horse appliances that have been used for over 100 years, it's much more likely that your fan has been painted, re-wired, and had a replacement part or a few added to it over the years.
So here's an example of what not to do when you're re-wiring a head-wire on your fan, I'll let the pictures speak for themselves!
Wow! Is that duct tape and silicone glue? YUP. Don't do this, guys!
And here's the beauty that lies beneath the duct tape. This is electrical tape. Fine if you're re-wiring a lamp but I would never use this on a professional restoration.