Are keel-stepped masts a thing of the past?

[Scott T-Bird]

Yesterday I had a chat with a new member at our marina who recently purchased an Allied Princess ketch. The boat is 45 years old and I was greatly impressed by its condition. It has certainly been cared for over the years. Sitting in the cockpit, I marveled at the condition of the cockpit and masts. There wasn't a scratch or any surface blemish anywhere to be found and all the surfaces were gleaming as if it just came out of the showroom! Brightwork was similarly in polished condition. The owner briefly told me that he was concerned and questioned the surveyor about the deck-stepped masts and was assured that there is no compromise.

It got me to thinking about modern yacht design and if keel-stepped masts are even designed for modern boats. It seems to me that deck-stepped is the norm, even for the upper-echelon of modern blue water designs. True or not?

 

[jssailem]

Not true.
Keel-stepped masts are easier to design (in my opinion). The deck structure can be a lot lighter without the need to engineer the supports to manage the downward pressure of the mast on the deck and upper sides of the hull.

 

[kloudie1]

As an Injun-ear, there are prs and cons. Both work well when properly executed.The primary load is downward from the stay/shroud tension. A compression post is generally lighter and less expensive than the extra mast extrusion.. I dunno

 

[shemandr]

All of my keelboats were deck stepped. A 1984 25', A 1972 29', and a 2002 35'. That spans 30 years of production boat building. That says something but I don't know what. Maybe just it's cheaper to build deck stepped masts. Or that 3 well known designers were designing for coastal cruising and never intended for their boats to go offshore. Or they were sensitive to water leaking in around the mast partners.
Only the 25' had deck compression and it didn't have a compression post.

 

[Crazy Dave Condon]

Have you ever removed keel stepped masts particularly when they are stuck plus the extra work to remove and install them? As a dealer, I had too which was one reason I never took any in on trade

 

[Scott T-Bird]

So my question is .... which boat manufacturers are currently building around keel-stepped masts?

 

[Scott T-Bird]

Not true.
Keel-stepped masts are easier to design (in my opinion). The deck structure can be a lot lighter without the need to engineer the supports to manage the downward pressure of the mast on the deck and upper sides of the hull.

I don't really buy that argument. Compression posts transfer the load to the keel or grid anyway and the shroud loads are also transferred to strong points below the deck. I don't think the deck or hull sides require any extraordinary design at all. I mean, the entire boat requires a comprehensive design anyway, so it makes no difference in design and probably not any material difference, either. Differences, sure, but not additional burden.

 

[Scott T-Bird]

Or that 3 well known designers were designing for coastal cruising and never intended for their boats to go offshore. Or they were sensitive to water leaking in around the mast partners.

Does it make any difference between a design for coastal cruising or offshore anymore? I'm guessing it doesn't. Sure, the traditional blue water design may have been for keel-stepped. But what about now?

It did surprise me a bit when I saw this 1979 Allied, which seems to me to be designed in the traditional manner for offshore sailing, but with deck-stepped masts (both main and mizzen).

 

[Apex]

racing oriented boats still have some keel-stepped models...

 

[JoeWhite]

Keelstepped is suitable and safer for ocean crossing, since there is less chance of loosing the mast as it is a single piece. My 1999 C36 is keel stepped and is not rated as blue water vessel, but I feel safer knowing that I have keelstepped.

 

[BAD ORCA]

I don't really buy that argument. Compression posts transfer the load to the keel or grid anyway and the shroud loads are also transferred to strong points below the deck. I don't think the deck or hull sides require any extraordinary design at all. I mean, the entire boat requires a comprehensive design anyway, so it makes no difference in design and probably not any material difference, either. Differences, sure, but not additional burden.

I think the problems with this idea is probably mostly revealed as the boat ages. If it is not carefully looked after and the structure under the compression post starts to become compromised, all sorts of very bad and expensive things can start to happen. I have seen this on one boat where the upper structure of the cabin was so deformed, there was no hope of repairing it, and it is a very well made 70's cruiser. The older boats with keel stepped masts also have their issues, but from my experience it mostly seems to just revolve around a corroded mast step, no structural problems.

 

[Scott T-Bird]

I think the problems with this idea is probably mostly revealed as the boat ages. If it is not carefully looked after and the structure under the compression post starts to become compromised, all sorts of very bad and expensive things can start to happen. I have seen this on one boat where the upper structure of the cabin was so deformed, there was no hope of repairing it, and it is a very well made 70's cruiser. The older boats with keel stepped masts also have their issues, but from my experience it mostly seems to just revolve around a corroded mast step, no structural problems.

My question isn't related to boats in the past and I'm not even questioning the pros and cons. We all have opinions for sure.

Are today's boats built with keel-stepped or deck-stepped? Is it sort of like the choice between Betamax and VHF. We know how that turned out (not that it matters anymore). I think I read that Oyster makes boats with keel-stepped masts. I'm wondering which manufacturers (if any) are making boats with keel-stepped. @JoeWhite has a '99 Catalina 36 with keel-stepped. My '99 Catalina 320 is deck-stepped with a compression post. Why the change? Is Catalina still making models with keel-step? Information about this seems to be a little obscure.

Are custom builders taking build preferences from the buyers in this regard? What are buyers demanding in today's market?

 

[dlochner]

A few years ago I had a similar questions and did some reasearch on the subject.

The key reason is a keel stepped mast can be made lighter and more bendy than a deck step mast. This because the loads are supported by the keel and the partners. It doesn't make much difference when the boat is at rest with no sails, however, when sailing to weather there is a lot of side ways loading. The loads on the mast can be supported in two places rather than one. It is also possible to move the mast butt fore and aft to change the rake and prebend. Again, think of prebend, it is easier to get pre-bend when part of the mast is supported above the butt.

 

[LloydB]

Just off hand I'm thinking that keel stepped mast would not be usually found on a steel sailboat but I don't know. On the other hand I suspect history will show that wooden boats of any consequence have often had the mast stepped on a keel simply because of the strength of the keel and the desire to keep the deck light as possible. An apparent choice of materials and engineering just as commonly made by the owner of a cottage or a mansion. Most everybody I know is aware that it's more complicated to live upstairs and often costs more but then you don't have to walk around the stuff that keeps it up in the basement.

 

[BarryL]

Hello,

Many current J boats are keel stepped. I believe that X Yachts are keel stepped. Salona Yachts are.

I suppose that boats that are more performance oriented have keel stepped masts.


Barry

 

[Tally Ho]

I bet Freedom Yachts are keel stepped (if you know, you know).

Greg

 

[Sailor Sue]

Regarding keel stepped vs deck stepped masts, I just received this email from a friend of mine.

 

[dLj]

The most recent Practical Sailor article that just came into my inbox talks about a brand new boat with keel stepped mast. Certainly does not seem to be a thing of the past...

"Are you interested in a 40 foot performance cruising sailboat? Looking for an X-Yachts sailboat? Join us today for a sailboat tour of the new X-Yachts X43. A 43.5 foot monohull fast luxury cruising sailboat we got to see at the Newport Boat Show. She features three keel options, two or three cabin layouts, vacuum infused fiberglass construction, and a keel stepped mast. If you’re sailboat shopping, we cover the pros and cons of this cruising sailboat and compare it to the Beneteau Oceanis 40.1 which is almost half the price."

Bold underline added by me...

dj

 

[Jim Legere]

The bigger Tartans have keel-stepped masts (e.g. the T3700). The Hallberg Rassey 400 has a deck stepped mast. Both capable boats currently being built. Different design briefs. I have had two deck-stepped boats and one keel- stepped. I liked the keel-stepped design best. YMMV.

 

[dLj]

I like my deck stepped mast. I always found it impossible to keep keel stepped masts from having some water infiltration - I really like a dry boat.

Even though deck stepped masts typically have a structural column under them, I've always found keel stepped masts to somehow be more 'intrusive' in the living space. I'm not sure why, perhaps they need more space around them to facilitate pulling the mast when needed.

Both systems work. If you are in such dire straights where there may be an advantage of being keel stepped over deck stepped then you are in such deep sh!t - I'd just really rather not be there....

dj