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One of None
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Discussion Starter #1 (Edited)
My boat is keel stepped. Removing updating, re-wiring the mast and painting it is the last of the "big" projects on my boat.

I often think/weigh the cost of a mast climber that I may never use; to the cost and practicality of having a tabernacle (build it with friends help) or deck stepped.

I know it IS NOT be easy to drop a mast of some 40ft even if it were "doable" it's essentially the same as doing all the work trailer sailors have to do.. only bigger and even heavier. (had a trailer sailor and sold it post haste!)

People with larger boats tabernacle/deck stepped masts Please chime in :)

Also, I've had thoughts of making the mast deck stepped.(unstoppable leaks) As I'm one of those people that can ever stop thinking of ways to change and improve things I love wondering about how to eliminate the mast/compression post because it actually blocks one end of the U shape settee in my boat. ( I know it can't be safely eliminated but I do wonder ) "a post at the bulkhead a beam and a post by the nav station, making the settee accessible from both ends." (Not gonna happen!)



To add to the discussion; are there any boats that don't have mast support without a compression post directly under it? (I've never seen it)
 

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69' Coronado 25
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My little Coronado 25 has a bridge that supports the mast, the mast is close to the starboard bulkhead but the support is the bridge. The teak beam behind my fat head.

 
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Master Mariner
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I don't think you can just decide to change a keel stepped mast for a deck stepped one, tabernacle or no. I think it would be necessary to have a marine architect design the changes. After all, it's not just about vertical pressures, but side to side and fore and aft. Probably much more cost effective to buy another boat.
 

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My Catalina 25 had a tabernacle deck stepped mast and it was always faster for me to climb it then to drop it. Dropping the mast and re-raising it was an all day project with 3 people if you also tuned the rig. Climbing the mast was a 20 minute project and could be done solo (safer with two). I think that equation would change on a 22' boat.

I can't imagine dropping the 38' mast on my Pearson 28-2 on the boat, even if I had a tabernacle. It is a lot safer with a crane.
 

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One of None
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Discussion Starter #5
Thanks guys.. again. it's a discussion. and my last big project. I'm liking the idea of a black mast. "black and tan" may be the new theme on my boat. so tired of blue and white hulls. Black sheer line stripe, black mast, tan decks and canvas.. Yeah.. who's going to pay for all this? LOL
 

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Corsair 24
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some boats have been successfully changed from keel to deck stepped I just cant remember which ones I read about

in simple terms its much easier to do it this way then going from deck to keel simply because those boats with no keel step would need to have the floors ripped out and beefing up of the area at the least, more than likely most never do so.

many boats like old albergs, pearsons of the time had massive wood beams, some laminated some just glassed in, some as part of a vertical beam on say a head bulkhead(some islanders do this)

all in conjunction with other structures to provide strength.

first off you would have to see if you have bulkheads nearby, if its possible to spread a beam the whole length(better) or if you can add or glass in a wood beam or plate etc...

on the deck side its a lot easier

fabricate a nice stainless mast base, add eyes for stuff like blocks and stuff, attach and through bolt, and if you want add tabernacle hinges on each side

any ss fabricator could do one for you or you could even retrofit one from another model boat.

then you have to deal with rigging unless you are really good eyeballing where to cut...but thats not that hard to do really

then like others mentioned the most important part here is the strength of the deck and cabin in general terms, will it bend and oil can? will it even be possible to reinforce space wise inside?

will you have to use tie rods internnally to prevent flex? etc...like a lot of thin, light weight racers do?

many things to look at...

but not impossible
 

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Denise, unless you have to do it to get under bridges, don't bother.

There have been many discussions about the inherent strength of keel stepped vs. deck stepped masts.

KISS. :)

Stu
 

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Some facts.

A keel stepped mast is supported at the mast step sitting on the keel and at the deck with wedges.
A deck stepped mast is only supported at deck level.

All masts is in heavy compression so they need a stiff support underneath.
It's easier to build this on a keel stepped mast than a deck stepped mast.

Since a keel stepped mast has two supports (keel and deck) a smaller (weaker) mast tube can be used. with the smaller mast tube is;
-Easier to bend.
-Lighter

That's the reason for most race boats have keel stepped mast.

There is not much difference between a deck step and a tabernacle with regards to load/strength.

Cutting down an existing mast converting to deck stepped might be a bad idea (depending on the mast section)

A compression post is the easiest way to support a deck stepped mast, it is the most lightweight design for the purpose

I have a keel stepped mast and there is no water entering my boat through the mast/deck ring.
 

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I think slowley. Neat Idea to think about. Stronger standing rigging required,
less deck stiffness, required for deck steeped. Think free standing mast. Without
keel and deck (very stiff) it is gone. Technician says sure it can be done just pay me enough. It falls in the same catagory of ideas as carbon fiber free standing, for me. Just the other end of the scale.
 

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One of None
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Discussion Starter #10
Seems to me the off cut of the keel stepped mast would become the compression post. :)
 

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Seems to me the off cut of the keel stepped mast would become the compression post. :)
Before doing so I would check that your mast profile is beefy enough to be converted to deck stepped on your boat.

For two similar boats only difference is mast vs deck stepped mast the boat with the deck stepped need a stronger mast prpfile.

It might be that the profile you have is strong enough...
Or that you need the mast profile one step up..

If the only aim is to stop water getting into the boat - there are other ways..
 

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yeap...that mast thread is a good read...its not JUST keel stepped or not...
 

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One of None
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Discussion Starter #13
water is coming down inside the mast. I'm not likely to do such drastic things but, it's good to kick it about with ya'll thanks!
 

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mine is a gusher too...Ive noticed in the tropical rains down here that most of the water is coming in through the holes for halyards and stuff and not from the partners, having said that my boot is old and crusty so I have taped it up for now...

but still my bilges are ALWAYS wet
 

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This will be brief since I had hand surgery and can only type with my left hand but here is an old discussion on this. http://www.sailnet.com/forums/boat-review-purchase-forum/3393-deck-stepped-mast-always-bad.html

Jeff
Hope you recover fast :)

Some comments to your old post - I do it here.

My objections to keel stepped masts are to the purely practical. Keel stepped masts mean that there is always water in the bilge. This water comes in at halyard boxes and other openings in the mast and nothing you can do will stop that.
There is something to do about this.
Selden have a document describing how to seal mast internally to avoid water getting in.
Have already liked this in my previous post but here it is http://www.seldenmast.com/files/595-814-E.pdf
My mast is sealed this way, there is no water coming down my mast.

Second, it is way harder to step and unstep a keel-stepped mast making the boat more subject to damage in the process.
Disagree, I have stepped / un stepped both keel stepped and deck stepped masts many times.
The rigging crane we have in our marina is a little bit shorter than the mast, the most critical part in un-stepping mast is when the top of the crane is close to the mast - the risk is waves from passing boats making the crane/mast collide.

With a keel steppe mast you can undo all stays/shrouds and still have the mast standing. we the swing the crane into position and lift out.
With a deck stepped we would have to keep the crane in position while undoing the last shrouds & stays supporting the mast, prolonging the time in this position.

With keel stepped it is of course important to keep the mast in correct angle while the mast is inside the boat.


My preferred set up is a deck stepped mast that has a welded flange on its bottom that is through bolted through the deck into the top flange of a structural aluminum jack post so that it transfers moment through the deck.
I have never seen this on a production boat, most mast manufacturers today will avoid welding on the mast tube.

My new boat has a keel stepped mast. If I go offshore it is my intent to pull the mast and have it modified to that arrangement if I ever go offshore with her.
Converting from keel to deck stepped might require that you need the next larger mast tube.
 

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Denise, are you still considering selling your boat? I hope not, either way (unless you are getting a new one!)

I ask because significant owner engineering mods are a major disadvantage.
 
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