Check out this video on a home made welding positioner. Brake disks, bowling ball and hyd jack. I can think of a lot of times I could use this one. http://www.youtube.com/watch?v=_OnF6_V28DM
And we thought Dyson Vaccum cleaners were the only ones who had balls. Now we know smart welders have them too
I have a bowling ball and two old used disc brake rotors in my shop! And I think maybe even a bottle jack. And some square tubing. Now I just need to figure out what the heck I would use that table to weld...
Take a minute with die grinder to soften the edges of the rotors and they probably won't chew up the bowling ball as fast. (the ball in the video looked pretty haggered on the bottom)
Maybe before cutting all apart, put it on a brake lathe and create a nice chamfered surface to contact the bowling ball.
All I need is a weld table to build the weld table on. That is the slickest idea I have seen in some time; gonna have to make one.