converting deck stepped masts to keel stepped masts

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Bruce Andersen
USA NCA Officer
Posts: 764
Joined: 25 Nov 2003, 00:06
Sail number: USA 16
Club: Famous Potatoes Sailing Club
Design: Brit Pop
Location: USA 16

converting deck stepped masts to keel stepped masts

Post by Bruce Andersen » 15 Feb 2004, 00:29

Has anyone come up with a slick method of converting deck stepped rigs to keel stepped rigs. I 2 boats, one of each type, and want to consolidate the number of rigs I have.

Ralph Knowles
Posts: 35
Joined: 23 Nov 2003, 22:51
Location: Dundee, Scotland, GBR1876/ GBR 2182/GBR 2167/GBR 1907/GBR 3367
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Mast Conversion

Post by Ralph Knowles » 15 Feb 2004, 00:53

Hi Bruce

Not easy to convert from deck to keel stepped without major 'surgery'. The stepping of the mast at the keel needs the installation of a mast box, preferably tied to the fin box to give it strength. There is also a need to support the mast both longitudinaly as well as axially at or above deck level. This is needed to control the shape and bend of the mast. Could get messy on a recognised design of hull. Why not just use your deck stepped rigs on your keel stepped hull by making up an extention piece/plug which stays with the keel stepped hull, and is used with all rigs.

Cheers

Ralph
Last edited by Ralph Knowles on 15 Feb 2004, 05:28, edited 1 time in total.

Bruce Andersen
USA NCA Officer
Posts: 764
Joined: 25 Nov 2003, 00:06
Sail number: USA 16
Club: Famous Potatoes Sailing Club
Design: Brit Pop
Location: USA 16

Post by Bruce Andersen » 15 Feb 2004, 04:48

Sorry, I guess I need to clarify my question a bit: I have both deck and keel stepped IOM's and would like to minimize the number of rigs I have to maintain.

Initially I was going to make a mast like extension that simply "plugged into" the bottom of the deck stepped rigs, but the fasteners from the gooseneck were in the way, and I worried about the rigidity of the joint. I'm not sure that an external collet that would go around the outside of the mast butt of the deck stepped rigs would be legal, as it would cause the mast to no longer be of uniform diameter.

Ralph Knowles
Posts: 35
Joined: 23 Nov 2003, 22:51
Location: Dundee, Scotland, GBR1876/ GBR 2182/GBR 2167/GBR 1907/GBR 3367
Contact:

Mast Mod.

Post by Ralph Knowles » 15 Feb 2004, 05:46

Hi Bruce

I was forgetting about the gooseneck screws. Any stub insert would have to be solid and have grooves to accomodate them, not an impossible task though. As for the 'uniform section' of the spar, this only applies between the lower and upper measurement bands.
What designs of yachts are we talking about. It may be possible to cut an aparture in the deck, to just be able to slip a mast box down to the keelson, heavily epoxy into place in the bilge and under the deck, and then trim off the excess at deck level. A tricky job with emphasis on proper alignment and a steady hand. Access to apply the epoxy would be important and not easy with big hands.

Cheers

Ralph

Bruce Andersen
USA NCA Officer
Posts: 764
Joined: 25 Nov 2003, 00:06
Sail number: USA 16
Club: Famous Potatoes Sailing Club
Design: Brit Pop
Location: USA 16

Post by Bruce Andersen » 15 Feb 2004, 17:31

Cockatoo & TS2. Perhaps if I epoxy the gooseneck fitting onto the mast, I can machine an internal fitting.

Steve Landeau
Posts: 256
Joined: 26 Nov 2003, 07:25
Location: USA 12

Post by Steve Landeau » 15 Feb 2004, 22:22

Hi, Bruce.
While I would prefer a keel step over the deck step, if using the same rig on both boats is that important, I would deck step it to the Cockatoo. That's the simplest way to make it work on both boats. Just make a plate (or buy one from Craig) to cover the mast trunk, and step it the same way as on the TS2.
I have also installed a mast trunk in a finished deck stepped boat (Ocka). It came out fine, and I can do it for you if you'd like to make the TS2 keel stepped.
Steve Landeau
AMYA 10859
IOM USA 112
Finn USA 112
Cal 25 #548

Steve Landeau
Posts: 256
Joined: 26 Nov 2003, 07:25
Location: USA 12

Re: Mast Mod.

Post by Steve Landeau » 15 Feb 2004, 22:30

Ralph Knowles wrote:Hi Bruce

As for the 'uniform section' of the spar, this only applies between the lower and upper measurement bands.

Cheers

Ralph
Joiners are allowed anywhere on the mast, internal or external, so long as they are the proper size (not larger than 100mm).
Steve Landeau
AMYA 10859
IOM USA 112
Finn USA 112
Cal 25 #548

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