Here’s some additional information about the rolla bolla from my comment on Cathy’s flickr set:
I now get to tell a story which may or may not add a little bit of a technical appreciation for what’s happening in this picture. My rolla bolla freaks other jugglers out. Mine is completely homemade. It uses a 4 inch diameter thick pvc pipe. The board itself happens to be exactly the same length as a shelf in a homemade bookcase I built for my dorm room in college because it is one the shelves which happen to be precisely 19 inches in length. Most jugglers are more accustomed to using rolla bollas closer to 3 feet long. For instance, Dube’s is 29 inches (btw, there’s your spec).
Juggling is all about physics. This is center of gravity trick. The longer the board, the greater the center of gravity. In essence, if you drew a line from the ground up to the top of your head (or the head fo the person on your shoulders) that divided your torso symmetrically and simply made sure that line never passed over your foot, you would never fall down. Since my board is so short, there is very little room for error. One way to cheat the physics is to use a larger diameter piece of pvc but frankly the 5 inch pvc tends to flatten a little taking away from the visual effect (in addition to simply being disproportionate to the other equipment and plain ugly).
Regarding the pvc when making a homemade rolla bolla. I learned the hardway that the pvc pipe should be the same width as the board (or slightly larger). If it is smaller you create a third degree of freedom and you might as well be doing this trick on top of a ball.
Don’t use those stupid stoppers on the bottom of your board! If you look at the Dube rolla bolla you will see that the underside of the board has stops at each end. This prevents the board from flying at high velocity to your left or right severely hurting people. Instead the board stops and you go flying at high velocity to the left or right breaking yourself and the people standing beside you. When we were first learning this trick. My brother fell off the board and sent it flying into a filing cabinet. 3 days later we were still trying to open the drawer. Without the stoppers you can safely take the board to the very edge without falling. I mean the very edge being exactly at the halfway point on the pvc pipe. Instead of the stoppers, control your board.
You can break things with a rolla bolla! These things may include: glass, bones, teeth, spines, and metal cabinets. When learning to stand on a rolla bolla do these things:
- Get a partner! Have the partner stand behind you with their arms underneath your armpits but not touching you. When you fall, they will spot you and keep you from breaking yourself
- Make sure your feet are at the edges of the board.
- Wear shoes!
- Practice daily in short spurts
- Start with the board touching the ground on one side and about one third of the board on the pipe. Starting by jumping up to a horizontally balanced board is cool and fun but an advanced trick that will land a beginner on their hind side.
The rolla bolla will increase your balance, develop your abs and back, and tighten your buttocks.
- Don’t let people stand to your left or right. I cannot emphasize this enough.
- If you fall…er…when you fall, think of yourself as being on a skate board or inline skate. Protect your wrists! Better to belly flop on concrete than to impact your wrist, elbows and knees
I will happily get together with anyone that wants help learning the rolla bolla.