# Mast types...? Through deck on deck...?



## marinesniper (Aug 2, 2006)

Hello, 

On my sailboat I have a mast that is mounted to the deck, meaning it does not protrude throught the deck into the galley like I see on other boat designs.

What is the reason for this...?
What are the positives and negatives...?

Also what is the correct terminology for these 2 types of setup...?

Thanks...

ms


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## PBzeer (Nov 11, 2002)

Other's will give you a better explaination of the pro's and con's, but they are called deck-stepped and keel-stepped. One advantage to the deck stepped mast is the ease of removal, especially for trailer-able boats.


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## marinesniper (Aug 2, 2006)

*Thanks now I can search more with the correct terms...*

I have a 30ft Cruiser... I live in Miami and have sailed to Key largo many times and biscayne bay. I plan on sailing to Key West next week and Bimini to Nassau in March...

I recently changed a chainplate for a lower shroud that broke...the mast did not move...and I have an deck stepped design. Also changed all the lower shrouds...

thanks again...


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## Jeff_H (Feb 26, 2000)

This is copied from a piece that I wrote for a different venue.....

"Deck vs. keel stepped masts

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. There is no right answer here. There is a contingent that thinks that the only proper way to step a mast is on the keel. There is a logic to that but it is a logic that can be engineered around and which comes out of a historical context that is less relevant with modern materials. 

To start with the basics, the base of a mast has a vertical and horizontal thrust to it that tries to push it down through the bottom of the boat and also sideward off of the mast step. In normal conditions the down load is several times greater than the side load. Beyond the loads imparted to the boat, there is also the issue of the loads that happen internally in a mast. When you look at the structure of a mast it is really a truss standing on end but it does not completely act as truss because the components of a truss are not supposed to have bending loads on them. Ideally the loads in the mast are primarily axial (acting along the length of the mast) rather than in bending (acting perpendicular to the long axis of the mast). Of course masts do have fairly large bending loads imparted into them. The two most often cited reasons for keel stepped masts being considered stronger is the way that the bending loads (moments) are distributed within the mast itself and the way that the mast imparts its loads into the boat. 

If the goal of designing a mast is to reduce bending moments within a mast, the greater the number of panels (segments between shrouds and other supports) the smaller the moments tend to be. In the days when single spreader rigs were most common a keel-stepped mast added one extra panel, the segment between the mast partners at the deck and the keel. This has become less significant as bigger boats have routinely gone to multiple spreader rigs and moment connections at the deck mounted mast steps. 


In terms of the way that the mast imparts its loads into the boat, masts are generally located in the area of the cabin trunk and because of the shape of the cabin (i.e. the deck folds up at the cabin side and horizontal again at the coach roof) this area, if not engineered for side loads is more prone to lateral flexing than would be the keel. One idea behind a keel-stepped mast being stronger is that with a keel stepped the mast is not supposed loads are put loads into the deck. 

In reality, this ideal is rarely accomplished for a number of reasons. First of all, if the mast is not tied to the deck or the deck tied to the keel near the mast, either with a tie rod or a tie from the mast to the deck and a connection from the mast to the keel, the downward force of the mast working in opposition to the upward loads of the shrouds can pull the hull together like a bow and arrow lifting the deck and separating the joint between bulkheads and the deck. You sometimes see this type of separated bulkheads on inexpensive or early fiberglass boats with keel stepped masts. 

Not only do keel stepped masts impart vertical loads into the deck (through the ties mentioned above) but they also typically end up imparting side loads as well (if they are going to reduce the moments in the mast as mentioned above). This somewhat reduces the structural advantages of a keel-stepped mast to next to zero assuming that a deck-stepped mast is properly engineered, and that is a big if!

There are several things that I consider critical to engineering a deck stepped mast properly. Primary is having a jack post below the mast. A jack post is a vertical member that carries the vertical loads of the mast to the keel. My preference is to have an aluminum jack post rather than a wooden one but a wooden post can work as well. The other issue is the distribution of the side loads. Ideally there should be a bulkhead or ring frame adjacent to the mast that can take the side loads and distribute them into the hull. These are obviously more complex to do than simply having a fat spot on the keel for the mast step to land on. 


My objections 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. Second, it is way harder to step and unstep a keel-stepped mast making the boat more subject to damage in the process. Beyond that if you loose a mast (I have lost two in my life) it is better in my opinion to loose a deck stepped mast because a keel-stepped mast is more likely to damage the deck when it fails and a deck-stepped mast is easier to clear away. The keel stepped mast advocates point out that you are more likely to end up with a bigger stump after the mast fails. I am not sure that that is the case if you are able to tow the rig as a drougue until things quiet down enough to rig a jurry rig. I am not sure what you do when the boat is being beaten to death by the upper portion of a mast that has buckled 20 feet off the deck at the spreaders. . 

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. My current boat has a keel stepped mast. It is my intent to pull this mast and have it modified to that arrangement if I ever go offshore with her. "


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## Cruisingdad (Jul 21, 2006)

PB is correct: Deck Stepped if on the cabin top. 

I am not qualified to give a whole history of the two, but I guess you will see some strong opinions wither way. I will tell you my perception:

Most of the original masts were keel stepped. My perception is that keel stepped masts are probably safer and more adept to offshore work. Just looking at it, consider how much harder it would be to demast a keel stepped versus a deck stepped. If that base plate moves or you somehow lose your compression post, it is gone. However, like all things in boats, there are drawbacks. One of the key drawbacks for a keel stepped mast is its tendency to leak. Even with all the new contaptions, etc, my guess is that you will always be faced with replacing/tending the collar.

Deck stepped masts seem to have grown in popularity among many, many builders. The reality of demasting a boat that is deck stepped is pretty darn slim. Most likely the forces that would require that are going to take down a keel stepped anyway. Deck stepped masts do not leak (well, hopefully) and are becoming more accepted even with the old traditionalists.

I have no doubt that there are design reasons for keel stepping masts (even today), but I would imagine you will see a continuiing trend toward a DS mast for reasons stated above. Just a note: Catalina 400 and 380's are deck stepped, the Catalina 36 is keel stepped. It is not necessarily a sign of a cheaper made boat... just design trends. 

A quick answer to the obvious reason for your post is: No. You have nothing to worry about with a correctly deck stepped mast and it is fine and safe.

- CD


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## Cruisingdad (Jul 21, 2006)

Uhh, yeah, what Jeff said.

Now Jeff, I type pretty fast... don't you tell me you just typed all that.

- CD

PS I guess I have always been under the impression that keel stepped masts were safer and less likely to demast. I can see you argument about the vertical loads... but not sure I totally agree that demasting with a keel stepped versus a deck stepped is going to be that much better. My guess is that the deck stepped will come right through the top of the roof. Hope no one was standing there. 

PSS I prefer deck stepped too.


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## TSOJOURNER (Dec 16, 1999)

The best way to settle this argument is to see how the best blue water sailboats handle this question. Shannon 43, IP, Valiant, etc. Hinkley, Alden, and others. What does Perry think?


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## TSOJOURNER (Dec 16, 1999)

Something I just came across from another forum.

They are great boats!! Cape Dorys in general are very well made. The only real flaw I can think of is that some of the Cape Dorys have deck-mounted masts, which can be an issue after years of use... Other than that...go for it.
__________________
Pete,
Hinckley 41 Standard


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## Tartan34C (Nov 21, 2006)

Jeff H,
I think an issue you didn’t cover in enough detail is how the type of step affects the rigidity of the mast and how that affects the choice of section. Euler's Column formula is used to determine the required moment of inertia of the section you need to handle the strain from the point loads of the stays and shrouds and the disturbed load from the mainsail. Part of the formula takes into account the type of ends the column has. A deck stepped mast is considered to be a pin end and a keel stepped mast is considered to be a fixed end. A keel stepped mast is 20% more efficient (ratio of effective length/length =.8) then a deck stepped one. This means for the same weight the keel stepped mast is not only stronger but is more rigid then the deck stepped one.

Either mast can be more then adequate for the job but a keel stepped mast is along the lines of a belt and suspenders approach to sailing. It is less likely to fail even if the lowers fail unlike a deck stepped mast which will almost certainly fail under the same conditions. I will not say that one is better then the other but a keel stepped mast does have its advantages and with some boats such as mine, a Tartan 34C the mast is not in the way because it’s in the head compartment.

You raise some interesting points but as you point out the final decision is largely based on factors that have nothing to do with the efficiency of a design and instead are based on emotion and habit. In short everybody has an opinion and there is no one “right” design for the job.
All the best,
Robert Gainer


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## Giulietta (Nov 14, 2006)

(EDITED Robert, I was writing when you posted!! Slowwwww writer, me!!)

The choice of mast set up depends mainly on the purpose of the boat.

They both good and bad. Depends. Many people want one set up other want the other set up. At the end of the day, the choice depends on what the boat is meant for. (opinions like allways, are just an extra. experience should dictate what you want on your boat)

For Cruising and small boats a deck step makes more sense, as it is easier to remove and transport. Also cruising boats normally do not require mast bend features, because they're not racing, and do not require built in mast tunings. Most prodctions use deck step to avoid the water ingression, and to make the mast smaller to ferry with boat when new.

As we move towards larger boats, mast transportation issues do not make a difference because the mast is already so big that 9 feet more do not make a difference, and you'll allways need a crane anyway.

I have a keel step mast for several reasons. One of them is because of the races. We needed a stiffer set up, to allow more mast control.

It allows better sail shape, specially on the lower end of the mast, because it allows to bend better to flaten the sail.

Initially we were going to have 3 sets of spreaders, but because it affects rating, we went for 2 sets and profitted the rigidity of the keel mast.

I can modify mast/shroud tension while racing, by using a special hydraulic jack installed under the mast, and can move the mast up or down according to the needs. So it needs to be bellow decks for this. We change tension when beating or downwind. It has a "locked" position so I can cruise with the family, too.

When deciding the inside arrangment of my boat, I moved the front bulkhead backwards and installed the mast in the front head shower, so all water that gets in is going directly to the shower drain. Solved a big problem here!! My mast boot is there for looks.

We needed the rigidity of the set up and my cabin was properly reinforced around the cabin hole for this purpose.

Also if still have some time to change tack if a shroud fails, before the mast colapses.

here are a few photos of the thru deck and mast installation.

Bellow the thru deck and on the bottom the mast base box, underneath it the hydraulic jack.










Mast installation


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## T34C (Sep 14, 2006)

I personally am torn between the pros/cons of each option and think (as everything else) it may depend on you personal preferences and type of sailing you are doing. My current boat has a keel steped mast, however I have owned several other boats with deck stepped masts. I tend to subscribe to the idea that Jeff mentioned about loosing the mast with it being keel stepped. With the bigger stump left behind I would hopefully be better equiped to jury rig a means of getting to safety. If in doubt please refer to the photo's of Ken Barns dismasted boat. (a discussion for another thread) There is a clear stump of a mast left that could have been used if needed. A deck stepped mast, while possibly easier to clear away would have been just that, cleared away. 

Jeff- I like the configuration you descripe with the deck stepped mast being bolted to the compression post, but wouldn't that negate your point in being able to clear away a deck stepped mast? I would be interested in your thoughts on smaller boats where a deck stepped mast is often bolted to the step, often in a configuration that allows it to hinge when stepping/unstepping. I was once dismasted in a small boat with a deck stepped mast and I can tell you that it ripped a very large hole in the deck when it went. 

One last thought. While it may seem over kill to some, my boats never leave the dock with out cable cutters and/or bolt cutters and hacksaw on board in case of such an emergency.


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## Giulietta (Nov 14, 2006)

Who is bolting the deck step mast to the compression post????


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## sailingdog (Mar 19, 2006)

It is very important to realize that a deck stepped mast has to be properly engineered, to transfer the loads from the mast foot through the cabintop to the keel. In older boats this was often done using a bulkhead, and that would cause problems if the bulkhead was damaged or altered. In more modern boats, the load is transfered via a compression post. If this isn't done properly, the tension on the shrouds and stays can cause the mast to compress the cabin top, leading to damage and possible delamination of the cabin top. 

I prefer the deck-stepped masts as it allows the cabin to have better water-tight integrity. The mast, in keel stepped boats, is often a source of water into the bilge. 

As for which is more likely to come down...neither...but if one does come down, the keel-stepped mast is far more likely to leave a long stub to jury rig something from, where the deck-stepped mast is more likely to be completely lost. However, that said, the keel stepped mast is more likely to leave a hole in the cabin top... so it is a toss up in my book.

PS... the compression post on my boat is through-bolted to the mast step on the outside of the cabin top. The post itself is a 2-1/2" x 2-1/2" stainless steel square column and runs from the hull, at the forward end of the centerboard case, to the cabintop.

Giulietta-

I don't think anyone is advocating bolting a deck-stepped mast to the compression post...just the compression post and the mast step itself...not the mast.


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## T34C (Sep 14, 2006)

Jeff_H said:


> 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. My current boat has a keel stepped mast. It is my intent to pull this mast and have it modified to that arrangement if I ever go offshore with her. "




G- That was taken from Jeff's last paragraph, if I am reading it correctly.


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## sailingdog (Mar 19, 2006)

Hmm... it looks like Jeff is advocating it.. I don't believe anyone makes a boat with a deck-stepped mast that is bolted to the compression post... it makes much more sense to bolt the mast step to the compression post, and then if you want, to bolt the mast foot to the mast step... you can... But I think it doesn't make much sense to bolt the mast itself directly to the compression post. You would have to unbolt those every time you wanted to lower the mast... and thereby lose some of the advantages of a deck-stepped mast and create more places for water to leak into the boat.


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## Giulietta (Nov 14, 2006)

SD, I went back and re-read it again, because soemtimes I need to read two or three times to understand...

"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."

Still did not understand...( the English I did) you guys make things diffrent over there......

As T said in another post:

OHHHH My!!!! Jesus, Mary, and Joseph!!!


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## Cruisingdad (Jul 21, 2006)

I am not trying to start an argument. When it comes to designs specifics and engineering, etc, I will tell you I am not the expert... as stated before. However, I cannot see how a deck stepped mast is better for offshore than a keel stepped. It would also seem to me that a properly engineered keel versus deck would be less likely to be dismasted. Maybe I am just splitting hairs, but I venture that if you took a pole on the number of dismastings, the reason there are so many keel stepped boats dismasted is that they were in the horrid conditions that might have taken a deck down earlier.

Not trying to be a smarty and start an argument. Sincere question: How can a deck stepped be better than a keel for seious offshore?

- CD

PS I still maintain that I like deck stepped better for obvious reasons.


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## Zanshin (Aug 27, 2006)

I think that a deck stepped mast is better when far offshore not because it is less likely to fail but that the consequences of a failure are less severe; as a keel stepped mast might take part of the deck with it when broken and swept overboard while a deck stepped one will leave the deck intact.


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## Giulietta (Nov 14, 2006)

Zanshin said:


> I think that a deck stepped mast is better when far offshore not because it is less likely to fail but that the consequences of a failure are less severe; as a keel stepped mast might take part of the deck with it when broken and swept overboard while a deck stepped one will leave the deck intact.


Zan, please note that (IF) the thru deck is properly engineered, it will hold the bending force on breaking. Its a feature when you build it. Unfortunately not all boats with keel steps can claim that.

I forgot how many times I posted this photo...

DO THIS WITH A DECK STEP.....Rest my case!!!










The whole story...
http://www.sailnet.com/forums/gear-maintenance/25854-here-story-you.html

For the record, I would never ever again have a deck step. I had a boat with one, a few years back. But what do I know, I don't read books...


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## Cruisingdad (Jul 21, 2006)

Zan,

I guess I would dissagree with that. I would think the deck step is EXTREMELY LIKELY to take a huge chuck of the deck with it when it comes back down through the cabin top... versus a keel step would be more likely to snap above deck. Someone else help me, but I recall pictures of the Fastnet where they showed the huge hole in the top of the cabin. And as I said before... hope you weren't standing there.


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## T34C (Sep 14, 2006)

Thanks for posting the photo G-. I had saved it to my computer but, as usual, couldn't get it on to a post! Now could you put the Ken Barns photo up??? 

I may be wrong, but I just don't see a keel stepped mast taking out a section of deck. It seems that the mast would exert lateral force on the partners during a dismasting which would be far less likely to fracture the deck than upward or downward force.
I do agree that neither options is more, or less likely to fail, if built correctly. Dismasting would be more of a failure of the rigging and chainplates than the mast itself.


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## Cruisingdad (Jul 21, 2006)

I think johnsail could provide some real insight into this. I think he wrote a book on the Fastnet race. Again, we are talking extreme conditions, but I would love to hear from another expert.


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## Zanshin (Aug 27, 2006)

I envision several mast failure modes but the most likely that I see is a stay failing and the resultant assymetrical forces breaking the mast. In this case the lateral forces on a keel stepped mast would make the failure point either the deck (if the deck is stronger on a horizontal plane than the mast) or {horror} the mast pivoting around the keel mounting point and tearing away a large chunk of the deck before {hopefully} being pulled out. This mode couldn't happen with a deck stepped mast, even after sliding off the mounting harpoint the forces would be more lateral than vertical. 
look at 2 distinct failure modes - mast breaking above deck and


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## Giulietta (Nov 14, 2006)

T34C said:


> Thanks for posting the photo G-. I had saved it to my computer but, as usual, couldn't get it on to a post! Now could you put the Ken Barns photo up???
> 
> I may be wrong, but I just don't see a keel stepped mast taking out a section of deck. It seems that the mast would exert lateral force on the partners during a dismasting which would be far less likely to fracture the deck than upward or downward force.
> I do agree that neither options is more, or less likely to fail, if built correctly. Dismasting would be more of a failure of the rigging and chainplates than the mast itself.


At your service.....


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## T34C (Sep 14, 2006)

Thanks G- !!

I would guess that is typical of deck stepped mast breakage like the previous photo. The force being applied at the masthead by the halyard and having an oposing force at the lower shrouds.


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## sailingdog (Mar 19, 2006)

I think the reason a keel stepped mast often damages the deck is that it does break higher up..and the mast falls and punches a hole through the deck where it hits. A deck-stepped mast usually breaks at the mast step and gets swept from the deck, not damaging the deck much otherwise.


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## TrueBlue (Oct 11, 2004)

Both masts on my ketch rig are deck stepped, and based upon the conclusive reasoning in this thread, I'm glad I have less potential for double trouble.


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## T34C (Sep 14, 2006)

SD- I think that is a good point, but with the force on the sail I would guess the masthead is "most likely" going to fall over the side. There is the possibility that I think Jeff mentioned that the keel stepped mast wouldn't shear off or break, but bend over (fold) and need to be cut off of the stump.


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## Giulietta (Nov 14, 2006)

OHHHH My!!!! Jesus, Mary, and Joseph!!!

Where this is going.....soon Michael Moore will be writing about this, too


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## T34C (Sep 14, 2006)

I think this thread has already included more facts than MM.

Boy G- you sure know how to throw fuel on the fire!!


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## TSOJOURNER (Dec 16, 1999)

If every part of a sailboat was evaluated this way prior to a decision to buy, the market would come to a halt. You need to have some confidence in the NA and the marine surveyor and the builder. As this discussion indicates the many factors that go into a sucessful design cannot be evaluated by laymen. Just buy a friggin boat and go sailing.


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## Cruisingdad (Jul 21, 2006)

Well, to set the record straight (as has been mentioned by myself and other previously and early in the thread) you will be fine with both. I knew this would start some debate. 

My questions was not if one was bad, but if one was superior to the other offshore, equal conditions.


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## Cruisingdad (Jul 21, 2006)

I, most unfortunately, am in Giu's camp - keel stepped is better than deck stepped. But I am no engineer - just using basic reasoning.


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## T34C (Sep 14, 2006)

Jeff- No disrespect intended, just interested in your thoughts on this. I have been thinking about your concept of thru bolting a deck stepped mast. It would seem to me (and my non-expert little mind) that you would have a system that creates the worst of each option. 1) By welding a plate to the base of the mast you may be trapping water inside the mast. 2) With out building the deckhouse to have a fore to aft slope, you would loose the ability to rake the mast. While you would still be able to bend the mast, it would seem that you would be creating undue stress on the metal near the base of the mast where the pressure of the bend would originate. As this would likely (maybe) be a bend that was held for long periods of time it would seem to create another possibility for failure down the road. 3) The advantage of being able to easily unstep your mast would be negated and open-up the possibility of water leakage thru the bolt. (as mentioned above)


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## T34C (Sep 14, 2006)

longwaterline said:


> If every part of a sailboat was evaluated this way prior to a decision to buy, the market would come to a halt....


And we wouldn't have Catalina's!!!!!!

Sorry CD, it was there!


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## camaraderie (May 22, 2002)

I listened to all the arguments for keel vs. deck stepped and couldn't make up my mind...so I got one of each! <g>


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## T34C (Sep 14, 2006)

Cam- That may be the perfect compromise.


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## JimHawkins (Aug 25, 2006)

Cruisingdad said:


> Catalina 400 and 380's are deck stepped





Giulietta said:


> For the record, I would never ever again have a deck step. I had a boat with one, a few years back.


Giu,
I didn't know you used to sail a Catalina! How did you like it?


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## johnsail (Apr 4, 2000)

*Deck- or keel-stepped masts?*



marinesniper said:


> Hello,
> 
> On my sailboat I have a mast that is mounted to the deck, meaning it does not protrude throught the deck into the galley like I see on other boat designs.
> 
> ...


The issue of where the mast is stepped (meaning where its bottom, the heel, rests) is important. There are trade-offs but I think the choice is pretty clear if you're going offshore, or sailing in SF Bay or another windy rough place, or eager to have a good night's sleep. To address the concern about what will happen if the mast breaks: if the heel of the mast is pinned in the step with a bolt -- and it really should be -- the mast will not fly around below if a shroud or the mast breaks above deck.

The big issue is the strength of the system as it's tied into the boat.

First, the pluses of a deck-stepped mast. If the mast's stepped there, there's more living space below, the mast is easier to step and unstep, and (a smaller thing) there are no partners (the hole in the deck) to attract leaks. You tend to see this arrangement on boats under 30 feet or so because the space below is limited and the loads are relatively small.

The advantages of a keel-stepped mast include stronger support by the boat for the mast, plus a smaller-diameter mast (the partners effectively add strength).

The downward force of a mast in a good breeze -- or when the boat's heeled a lot, or when she's pitching or rolling -- can be phenominal. Rod Stephens, the great rigger and spar designer who worked with his brother, Olin, at Sparkman & Stephens, described the "tendency for the shrouds to push the the mast down through the bottom of the boat." The calculations for a boat that I've just written a book about, Bolero, produced a maximum downward force of 14,700 pounds a square inch -- enough to deflect the hull by 6 inches unless the loading were spread properly with a huge mast step. Admittedly, she's a hell of a hefty boat. But every sailboat faces this problem to one degree or another.

My preference is a mast stepped on the keel. It's typically bigger and stronger than the deck. Either way -- deck or keel -- the step must be engineered to take and spread a big load so the boat doesn't deflect or bend. If you're looking at an older boat, tell the surveyor (always get it surveyed, right?) that you're especially interested in the standing rigging and mast step. If you're looking at a new boat and the sales guy spends a lot of time talking about all the space that's saved in the head because the mast's deck-stepped -- well, if I were you, I'd start jumping up and down on the deck near the mast step to see if it gives.

John Rousmaniere


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## TSOJOURNER (Dec 16, 1999)

Have had both deck-stepped and keel-stepped. Prefer deck-stepped, the boat stays dry inside. Need to have a compression post or bulkhead underneath the mast step though - nothing else works. Have seen a boat that had a deck-step and a curved support inside that was supposed to disperse the compression load all over the boat. It did disperse it, directly out to the sheer - pushed the sides of the hull out. Headroom in that boat varies with windspeed...


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## johnsail (Apr 4, 2000)

Sailormann said:


> Have had both deck-stepped and keel-stepped. Prefer deck-stepped, the boat stays dry inside. Need to have a compression post or bulkhead underneath the mast step though - nothing else works. Have seen a boat that had a deck-step and a curved support inside that was supposed to disperse the compression load all over the boat. It did disperse it, directly out to the sheer - pushed the sides of the hull out. Headroom in that boat varies with windspeed...


That indicates how much load a rig presses on a hull, and also how a well-engineered post can do the job. How big is the boat?

For those who'd like to read up on rigging and masts, take a look at Rod Stephens' chapters in "Desirable and Undesirable Characteristics of Offshore Yachts," a technical book I edited about 20 years ago that's still relevant (and still in print). He and the other designer-writers (who include Bill Lapworth, Ted Hood, and Olin Stephens) look at ocean-going boats in a way that some might call conservative. The writers' track records are pretty good.


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## T34C (Sep 14, 2006)

johnsail said:


> That indicates how much load a rig presses on a hull, and also how a well-engineered post can do the job. How big is the boat?
> 
> For those who'd like to read up on rigging and masts, take a look at Rod Stephens' chapters in "Desirable and Undesirable Characteristics of Offshore Yachts," a technical book I edited about 20 years ago that's still relevant (and still in print).


Thanks John. I will try to find a copy.

_He and the other designer-writers (who include Bill Lapworth, Ted Hood, and Olin Stephens) look at ocean-going boats in a way that some might call conservative. The writers' track records are pretty good_

It is hard to argue with the fact that S&S boats have never lost a mast due to design. (Apart from 1st mast in Intrepid.)


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