Balls or not...

[Inquisitor]

Figured that would get someones attention.

I am looking for some piece of hardware. Since I don’t have a clue what its name might be, I’ve had a devil of a time trying to locate it on the web. I want basically a ball and socket joint so that I can have a rotating mast that can also be lowered to the deck. Is there an off-the-shelf product or is this unheard of?

[Chris Ostlind]

Pretty much most beach catamarans will have this exact type of mast mounting rig and the parts are readily available in the new as well as used market.

The setup could be a straight across fit for you if your mast has a similar extrusion.

Then again, you could always use a complete rig from a beach cat and have full compatibility.

Chris Ostlind

[Inquisitor]

Yes, I have a Hobie 16' and it has that. Unfortunately, it depends on gravity and stay tension keeping it seated. I need something that traps the ball. It would also have to have some kind of mechanism to then release the ball.

[D'ARTOIS]

There is a system that you will find in the camerasupport of a large cinema-tripod.
In this head of the tripod, you will find a ball joint that can be trapped and fixes the sleigh of the large cine-camera in a particular required position.

I hope this helps you a bit....

[chandler]

Sounds like a derivation of a giant air hose fitting.

[Chris Ostlind]

"I need something that traps the ball. It would also have to have some kind of mechanism to then release the ball."

Perhaps you could explain as to why you need to have it captured in a socket that is releasable?

If the ball can be released from the socket then you are always depending on some mechanical function to keep it there. How is that any different from a rotating cat mast except in the details of how the mechanism is arranged?

Is this a safety issue, pure personal quest issue, or is there a purposeful reason for all the extra cost and machining that would be necessary? Since your mast is being held up by the shrouds, anyway, why thje preference about how the ball is held captive?

Chris

[Inquisitor]

I wasn’t trying to be mystic… I just thought it would be a simple request. I just assumed that there would be more sophisticated ball joints for boats other than my lowly Hobie.

I was thinking something along the lines of a trailer hitch ball. However, 1 7/8s seems a little overkill for a 40’ mast. Also, it does not need to have a “mechanism”. It would only be used to totally de-mast the boat. I’ve seen the ball joints for low-end camera tripods but felt they were way too light. Maybe, the similar joint D’Artois suggests for large-format cameras might be closer to what’s necessary, but I’ve never seen one of those. I also need to dig up what Chandler suggests. Again, an image is not ringing a bell.

1. It needs to totally fix all three displacement degrees of freedom (DOF).
2. The rotation about the mast axis must be unhindered for the full 360 degrees. My Hobie joint only allows about +/- 30 degrees rotation about the mast.
3. One other rotation DOF must allow the mast to be lowered to the deck.
4. The final rotation DOF must allow limited (say +/- 20 degrees) of rotation.

Basically the miniature table-top camera tripod ball joint is exactly the joint I need… just more substantial. Again, I just assumed that all these larger/higher-end boats with rotating masts would use some nice ball joint.

[Thaddeus]

Go down to your local auto parts store and buy a ball joint and carrier. Done.

[chandler]

From what I know of automotive ball joints, they are kind of permanent unless you have specialized tools.

[Thaddeus]

Make the joint removable from some sort of clamping block affixed to the deck.

[D'ARTOIS]

I was not talking about the small ball joint of a table tripod but rather the heavy one that works with a Panavision Camera that weighs around 25 kgs; I have one in France. That is really a heavy ball joint and is fixed by fastening or undoing a kind of handle that is mounted on the swivellin head.
I have never took the thing to parts as I hardly touch a camera nowadays.
It is just the idea - if you knoe some hollywood technicians, they might help you because there are even heavier ones.

[Robjl]

Check out www.ronstan.com they have just about everthing.

[chandler]

Thaddeus,
Along the lines of a ball joint, how about a ball joint and a ujoint? Or just a ujoint?

[ABoatGuy]

Along the lines of a ball joint, how about a trailer hitch and ball. Turn it over. Copy it in a suitable material for corossion etc.

[chandler]

There you go,killed 2 rocks with one stone.