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post #11 of 36 Old 02-14-2012
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That is basically what I had in mind. My intent was to build up the strength of the deck below the mast and insert and glass in an aluminum spacer between the king post and the above deack bearing plate.


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post #12 of 36 Old 02-14-2012
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Jeff.. do you think you would be as easily able to induce the required prebend with a deck stepped set up (esp on your style of boat?)

Otherwise I too prefer the deckstep primarily for the potentially dry bilge..

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post #13 of 36 Old 02-14-2012
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"Do you think you would be as easily able to induce the required prebend with a deck stepped set up (esp on your style of boat?)"

Ron,

I do think so. The key is getting a moment connection at the deck between the base of the mast and the king post. That was how the Laser 28's were built which has a very similar rig to my boat.

Jeff


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post #14 of 36 Old 02-14-2012
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Do you really want the fiberglass around the mast to be stronger? Not more flexible? It sounds to me like this bolted-together mast is really just a keel-stepped mast with slots cut in it that a sheet of material goes through in order to keep water out of the boat.

I'm (obviously) not a nautical engineer, but it seems to me that you want the fiberglass right around the mast to be more flexible - like the boot around the keel-stepped mast -- to prevent any horizontal movement of the mast from damaging the "real" deck.
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post #15 of 36 Old 02-14-2012
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Having had both, I prefer deck stepped masts, for the reasons given. I use a heavy plate arch connected to the chines to prevent the mast support from intruding into the interior design. This arch is far stronger than any extension of the mast would be.
When I bury the side decks, the lee shrouds don't even slacken , in the least.
Those who build my boats with a keel stepped mast, eventually go for a deck stepped mast, when re-rigging.

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post #16 of 36 Old 02-14-2012
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The arguments against a deck stepped mast that I have heard primarily go to a deck stepped mast with no support post, IE arch, or thickened deck to support the downforce of the mast. In these water intrusion of core material, or arch can weaken mast base to dangerous levels. Second more of a stub to rig makeshift mast, I'm not sure I follow that one, with a wooden mast maybe.

Not having tried to rig a makeshift mast on either types of boats, I'm not sure how it would work, but IF I had to I would start with using my cordless drill to drill holes in the base of whichever is longer, remains of mast, or boom, then attaching stainless screws to el brackets. With a keel stepped mast assuming you still have a cabin top, the mast will remain upright while you rig shrouds, but you will have a large hole left from the diameter change of original mast to makeshift mast.

With a deck stepped mast you would prerig shrouds first, then screw el-brackets to old plate on deck leaving your boat in original configuration with a shorter mast.

I my opinion is lashing a mast fragment to a stub of a mast would be an excercise in futility, try lashing two sticks together and then put a side load on them.

Generally speaking a keel stepped mast might be less vulnerable to dismasting, but a deck stepped mast would be easier to repair at sea, in both cases raising a mast in a rolling sea in a single masted vessel is going to be problematic.

I would say even in calm seas raising a mast of any size would be not only impossible, but extremely dangerous.

It may not be very seaman like for me, but if dismasted, and engine failed I would call for help, if dismasted and engine working, (or fixable), I would motor to nearest landmass.

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post #17 of 36 Old 02-14-2012
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Quote:
Originally Posted by CapnBilll View Post

Not having tried to rig a makeshift mast on either types of boats, I'm not sure how it would work, but IF I had to I would start with using my cordless drill to drill holes in the base of whichever is longer, remains of mast, or boom, then attaching stainless screws to el brackets. With a keel stepped mast assuming you still have a cabin top, the mast will remain upright while you rig shrouds, but you will have a large hole left from the diameter change of original mast to makeshift mast.

With a deck stepped mast you would prerig shrouds first, then screw el-brackets to old plate on deck leaving your boat in original configuration with a shorter mast.

I my opinion is lashing a mast fragment to a stub of a mast would be an excercise in futility, try lashing two sticks together and then put a side load on them.

Generally speaking a keel stepped mast might be less vulnerable to dismasting, but a deck stepped mast would be easier to repair at sea, in both cases raising a mast in a rolling sea in a single masted vessel is going to be problematic.

I would say even in calm seas raising a mast of any size would be not only impossible, but extremely dangerous.

It may not be very seaman like for me, but if dismasted, and engine failed I would call for help, if dismasted and engine working, (or fixable), I would motor to nearest landmass.
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post #18 of 36 Old 02-14-2012
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Quote:
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I personally strongly prefer a deck-stepped mast over a keel stepped mast but once again this is an area where opinions can differ widely.
I mainly quoted the above to give the link back, I deleted most of Jeff's post.

Jeff_H, I want to state that I greatly admire your posts, and make a point to read all that I see. You personify the old saying of "he's forgotten more than I'll ever know". You also write well, express yourself clearly, and don't try to talk over our heads. You are interested in imparting knowledge, not showing off. Thank you for taking the time to educate us and share some of your insights.

I'm a novice in comparison to many, but I have had both types of mast steps. I will never own another keel stepped mast. The amount of water that streams down a mast during wind and rain is incredible, lots of it goes into the bilge with a keel stepped mast no matter how you try to keep it out. I've had one dismasting with a keel step, and it tore the cabin top as it came down. I was able to limp home under sail, using the boom to "sort of" hold up the main.

Raising and lowering a deck stepped mast is so much easier and safer that there is no comparison.

Last edited by skygazer; 02-14-2012 at 09:34 PM.
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post #19 of 36 Old 02-15-2012
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I have had both and like the deck stepped for being less wet as others have stated.

Some people feel the keel stepped is stronger, but I doubt it being im portant even if it is.

This is just another thing people spend too much time thinking about because they somehow think they know more than the boat builder.

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post #20 of 36 Old 02-15-2012
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+ 1 that it's a matter of opinion. I certainly wouldn't shy away from another deck-stepped mast (I have had both).

I was dismasted in the deck-stepped mast, which had nothing to do with the way the mast was engineered. In that case, it probably wouldn't have mattered which method of "attachment" I had.

Having said that, though, if a rig failure is something less than catastrophic, you're probably better off with the keel-stepped mast.
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