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rickinnocal
09-08-2010, 10:35 PM
Hello, everyone.

I've got my "Glory B" back in the water after haul out, and will soon be getting ready to install a mast. http://i829.photobucket.com/albums/zz213/rickinnocal/Refloat%20day/BlackGunwale.jpg

She is a 54' Calkins designed sloop that was launched in 1996 and never completed, so she has never had a mast stepped at all. I have found a wooden mast to use, but would be interested in seeing some photos of various peoples mast collars and keel steps.

I have a wooden planked deck, with two mast partners about 12" apart either side of where the deck hole will be cut. The boat has a solid oak full length keel, under which is a full length steel box keel, from which hangs a formed fin keel. (The oak keel came from an old USN personnel launch - I doubt one could even find an oak timber that size these days!) Where the mast - 7" diameter - hits the keel it will be sitting directly on the oak keel, so there'll be no need to spread the load over ribs or floors.

What do other people have for steps and mast collars? I'm thinking - since it's a wood mast / wood deck - of having a shaped round hole turned into a hardwood board to fix between the partners - sort of like this..... http://i829.photobucket.com/albums/zz213/rickinnocal/Collar.jpg

Could some of you with similar style vessels post some pics of what you have, please?

Thanks
Richard

Ian McColgin
09-08-2010, 10:43 PM
The collar wants a groove for securing the mast boot. It may be well to make the hole diameter a nudge larger than the hole in the deck and partners so that you can be sure the wedges bear on the parnters, not the collar.

Putting the step right on the keel seems like a good way to induce rot, but if you don't plan to keep the boat more than a decade or so, its SOEP.

G'luck

rickinnocal
09-08-2010, 10:59 PM
The collar wants a groove for securing the mast boot.

Yes, that's planned, I just didn't put it in the sketch.


It may be well to make the hole diameter a nudge larger than the hole in the deck and partners so that you can be sure the wedges bear on the parnters, not the collar.

The mast is 7" diameter, roughly, and the partners are 12" apart. I was planning to have the square part of the collar below the deck, fixed to the partners, with the round section protruding up through the hole in the planks, and have the wedges riding between the mast and collar. Are you saying I should make a 12" diameter hole so that the front and back wedges ride between the mast and partners? That would make the wedges about 3" thick or so.


Putting the step right on the keel seems like a good way to induce rot...

Why would that be? On top of the keel is about 6" or so up from the bilge, so I thought it would be OK. Would you advise making a block of some sort to sit on top of the keel? That's exactly the sort of advice I'm looking for.


its SOEP.

Sorry, I don't know that term.

Richard

Ian McColgin
09-08-2010, 11:08 PM
SOEP - SomeOne Else's Problem.

The collar is not the strong bit. The partners are. Make your hole and wedges accordingly.

Steps can be made in many ways but for wooden masts, there's often a bit of a tenion sticking down and the mast has a female trough to recieve it. This is a place that needs drainage. If it's just cut into the keel, you can't drain and you'll get rot into the keel as sweetwater provides part of the environment.

A nice step has its bottom a quarter inch or so above the keel, bolted on and obviously will need bracing laterally and fore and aft. Lots of good models to derive this from.

If the tenion is the full fore and aft size of the mast, then you can easily make the slot in the step a little long in both directions and use wedges for final location, giving a bit more control over how you tune the rig.

G'luck

gibetheridge
09-08-2010, 11:08 PM
SOEP?

According to Chapelle the mast step ought to be notched over several floor timbers, which are themselves notched for the step, thereby insuring that once it is fastened in place it will stay put. This would also help to avoid rotting the keel.

The mast should be tenoned and fit into a mortise in the step, and the mortise should have at least one drain hole going out thru the bottom.

A space between the step and the keel sufficient not only to provide ventilation but also to allow for cleaning will be appreciated in the future.