Make a metal ball hook swivel

[ukspeedbag]

Thanks for sharing your thoughts. I think there is some math an engineer could occupie himself with for some hours. Me? I like to try things. I let you know when my experiment is bagged ;-)

I look forward to seeing it in action. It's always good to experiment.

[paranday]

Thanks for sharing your thoughts. I think there is some math an engineer could occupie himself with for some hours. Me? I like to try things. I let you know when my experiment is bagged ;-)

Was looking at novaspeedbaggers recent video, and noticed something unique about ball hook swivels -- the final pivot point of the bag is a moving target. It's always shifting from side to side. The final pivot is off the eye hook, the primary pivot is off the ball. Maybe this feature of a "compound pivot point" is part of what gives the ball hook its unique feel. All other swivels that I'm aware of pivot from the center of the platform, always.

See attached photo -- the ball pivot is maxed out against the side of the swivel housing, yet the bag is nowhere near the board.

Swivels. I dream about them...

[baggins]

^ I see your point. A long connecter rod will make the bag
Flex in its loop attachment, just like an extra link will. To the drawingboard

[baggins]

But if one could make a housing, which were imbedded in the platform, the higher placed centre of rotation will allow the use of a linkless connecterrod. Especially if one could combine this construction with a larger ball contributing to greater range of motion. I'll have to look more into this....

[PIEFURZ]

I think the issue is a one of physics, if only I would have learned it. I'm interested in things like this but as we see it can get deep. It kind of reminds me of standing up in a swing and pumping to go higher then jumping out. It's a wonder we survive childhood. The swing would have chains or rods about a foot long with eyes to link them together. They wouldn't have a long single rod from the swivel point to the seat. I think the ride on something like this would be weird. It may be that swivels need links to keep them swinging smoother. Or maybe it is that the bag is hit around and the links just keep it at the given distance from the board so the links have to be flexible enough in all directions to follow the bag. Also the bag is subject turning so something like a fixed rope without a turning point at the board would twist up. A short chain or rope may sound like it would work except for the twisting probability. I'm thinking levitation or magnetic field to keep the bag moving under the board.

[paranday]

...Also the bag is subject turning so something like a fixed rope without a turning point at the board would twist up. A short chain or rope may sound like it would work except for the twisting probability.

You can tie a speed bag to a fixed (non-movable) eyebolt, and it sort of works as a swivel, at least for front to back punching, but, as you say, it does get twisted up. Using a lightweight ball bearing to make the eyebolt spin freely works really well to eliminate twisting.

I'm thinking levitation or magnetic field to keep the bag moving under the board.

A maglev speed bag. Now that would be cool.