Ventilator Bitts

[Sailor]

Here's the idea. Everyone has see the beautiful bitts that were found just about everywhere on old sailing ships. Some had a star cast in the top of them, others were plain. I'm trying to come up with a way to turn them into ventilators as well. Some form of screw cap so they could be shut tight in bad weather but opened for the nice weather and in port. How do you incorporate some form of Dorad style (or any other style really) of baffle inside the bitt so that it is strong enough to be used as a bit but also hollow and usefull as a vent? Any thoughts on this? The only thing I can come up with is build a Dorad box under it and install the bitts in such a way that the spray and green water is knocked down before it goes below, or have some sort of mushroom cap sort of arrangement with the top of the bit. I would also like to have something cast into the top of the bit, an anchor maybe? The problem I keep coming up with is how to cast the shape I dream up to accomplish the task. Anybody familiar with casting know of any of these in existence? Another thing would be to have some sort of lip cast into the top below the screw part to keep the line from riding up on the bit and blocking the airflow. Let me know if you engineering minded types can come up with something or if you know of it already out there. Another idea I had was a marker for my kingspoke. Picture this...... A Crown Royal bottle cap cast in bronze. A perfect crown for a kingspoke. Let's hear your ideas folks.

[Jay Greer]

Certainly a provocotive idea! Pete Langley at the Port Townsend Foundry would be your best bet for a consultant.
I can envision several possibilities but they are all subject to R&D costs.
JG

[paladin]

depending on the style of the boat...and whatever may seem appropriate....but I sketched up a mooring bit for a "workboat" made frome 3 1/2 inch stainless pipe that had a double baffle inside and an air inlet so that a small fan could pull air through it to below decks.....similar ideas could be used with square tubing...

[rbgarr]

Bror Tamm, former spar builder and boat builder for the defunct Lawley's (Neponset, Massachusetts) drew designs for what you are talking about. He built small boats, oars and paddles and made patterns for fittings for L. F. Herreshoff, as well as being deeply involved with some of his R boats in the 20s and later.

IIRC most if not all of Tamm's tools, fittings, clippings and designs went to Mystic Seaport, but I've not seen his collection referenced in their Ship's Plans online index.

Sparkman and Stephens also incorporated vents into cutters' staysail tack 'stands' (some call them spiders) at owner's requests.

I'd be tempted to try it by including the opening/closing mushroom vent offered by Davey.

Good luck.

[Jeremy Burnett]

Over here I think these are called"Nicholson" vents,maybe they came from Camper and Nicholson the yacht builders or Ian Nicholson the designer.Basically they are a dorade system made with one tube inside another with hole in the tubes to allow air flow.It means you can have a vent and sampson post or bollard combined on the foredeck.
I would recommend Ian Nicholsons book "Designers notebook.Ideas for Yachtsmen" Its full of interesting bits and pieces.Published in USA by Scribner, ISBN 0 229 97490 2.

[shamus]

Alan Payne drew a combination bitt ventilator on many of his plans, but I don't have detail drawings.

[John E Hardiman]

Quite common in steel barges, there may already be a steel off-the-shelf unit out there.