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 Post subject: 21SE ..smaller rig for
PostPosted: Thu Mar 19, 2020 4:51 am 
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Hello All,

I'd like some advice on the best option for putting a smaller mast/sail on a 21SE. Where I live it is windy more than its not windy and my preference is to be able to handle 20-30 when it pops up..and be somewhat family friendly. Racing and maximum performance is not a goal. Having fun when its blowing is.

Also I'd prefer to have a bit less bulk to deal with, esp in terms of mast stepping.

In my area there are some 18 masts available and a mast from a Miracle 20.

The Miracle 20 mast is 31' long, I think so maybe still a bit on the big side? The 21SE mast is 33', so that's just a 2' reduction.
I'm leaning toward an 18 mast which at 28' seems like the right step down. I'd then get a nice set of modern sails for it. But before I pull any triggers I'd like to get some knowledgable input.

Also, I have to think that a Getaway rig would be going too far down the scale?

Thank You,
Robert Netsch
Nags Head, NC

ps - this also means that I'll have a 21SE mast/boom/sail that is no longer needed


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PostPosted: Thu Mar 19, 2020 12:37 pm 
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Joined: Mon May 09, 2005 10:25 am
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Location: Jersey Shore
A couple notes:

While it is true that the H20 mast is only 2 feet shorter than the 21 mast, it is also a much smaller cross-sectional profile, so its weight per foot is significantly less than the 21 mast. Overall, it should be considerably lighter than a 21 mast. That said, you would most likely still need a gin pole or winch to assist with raising.

If you shorten and reduce the cross-section by going with a smaller mast, you will increase the likelihood that the boat will turtle if you capsize. Probably want to consider a mast float if you go this route.

sm


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PostPosted: Thu Mar 19, 2020 1:24 pm 
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Location: South Boardman, Mi
The 21SE is a heavy wide boat. Put some people on it and it takes a lot of force to flip. What this means is that a mast that is strong enough to carry a H18 sail on a H18 may be too weak on your boat.

That said.... my 21SC is rocking a modified H18 mast. It steps easy and fits the 21SC sail. I believe the H18 boom is shorter than the 21SE boom, but this shouldn't be a problem. Just run the 21SE boom with the H18 sail.

On my boat I wanted to maintain the original 21SC boom clearance and mast height. To do this I extended the bottom of the H18 mast with a long custom made mast base. A long mast base is unnecessary for you. Just find a way to adapt to the H21 mast ball and you are good to go.
https://www.hobie.com/forums/viewtopic.php?f=45&t=61361

I would recommend a mast bob and shroud extenders for righting.


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PostPosted: Fri Mar 20, 2020 4:48 am 
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Thank you for the replies.

I have a similar thread going on TheBeachCats and good input over there as well. It sounds like the simplest thing is to just get reef points in main or maybe a smaller sail period, and live with the massive mast.

It sounds as if a smaller mast leads to challenges with 1) jib shape/angle, 2) core strength as needed for a bigger boat, and 3) higher chance of turtle.

The turtle risk can be somewhat mitigated with a big mast bob (kooky i know, but practical), shroud extender, and what I like to think of as prudent boat handling.
Would not the stress on the mast be a function of the sail area and wind strength more than boat heft? I like to think a H18 or H20 mast can manage the job, but maybe that is just wishful thinking.
The jib may be the hardest part to sort out. Of course it will be on a roller furling but it obviously needs to have a nice shape for function and enough size to help the beast tack.

Robert


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PostPosted: Fri Mar 20, 2020 5:32 am 
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Location: South Boardman, Mi
The load on a mast is equal to the force exerted on it by the wind... until the force on the rig exceeds the boats righting moment and the boat tips over. Additional wind may slightly increase the force and flip the boat even faster.

Calculating the loads is tricky and beyond me. The factors are as follows: The loads on the mast come from many sources. The wind pushes on the sail, which in turn loads the mast and the running rigging in a complex manner. Add to this the loads from the downhaul, outhaul and mainsheet. Oh, and the mast has tensioned diamond wires and it rotates. Balance this against righting moment, which may be the righting moment preventing a pitchpole or it may be the righting moment during a capsize.

So, is a H18 mast strong enough? sometimes, maybe, hopefully? If mine snaps in half you'll be able to read about it on this forum.


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PostPosted: Fri Mar 20, 2020 5:21 pm 
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Joined: Mon May 09, 2005 10:25 am
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Location: Jersey Shore
The load on the mast, in a very simplified way, is a function of how much righting moment can be applied to the rig. Righting moment is a function of mass (the boat’s and the crew’s) times the distance from the fulcrum, which in this case is the leeward hull. The width of the boat is fixed by design and cannot change (for practical purposes). The mass of the boat is fixed, and about 50% greater on a 21 vs an 18. The max crew weight is determined by the bouyancy of the hulls (once the leeward hull submarines under the weight of the crew, no additional weight can be added), which is significantly higher on the 21 as compared to the 18.

Bottom line, a 21 is capable of generating significantly higher righting moment than an 18 and that will directly translate into loads on the mast potentially beyond the design range. Not a guarantee it would break, but certainly a possibility.

sm


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PostPosted: Sat Mar 21, 2020 1:45 pm 
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Location: Columbus, Indiana
Back in the later 90's, my kids were young. I did not want to discourage them from sailing on high wind days. So I had Randy Smyth design me a "storm" jig that we used a few times. Maybe 20 times total. Even the fabric was heavier. That sail has been part of my inventory since. It has not been used in 20 years but care for as it is stored in my rack of extra sails suspend from my garage ceiling inside of spiral pipe. What can I say but as a sheet metal worker that was one of my specialty.

If anyone is looking for a smaller jib sail for your 21SE....I would probably make it available to them. :wink:

--
Bill 404 21SE

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Bill 404 21SE
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PostPosted: Mon Jun 22, 2020 3:29 pm 
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Joined: Thu Jul 25, 2019 1:04 pm
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Location: Granger, IN
Robert,
I have a 21se that was tossed in a storm along with her lift.
I'm looking for a mast and sail to replace what was damaged.
If you decide that you wish to downsize your rig and wish to sell please contact me.
Thanks,
David


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PostPosted: Tue Jun 23, 2020 5:25 am 
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Sorry to hear of your mast misfortune.

The jury is still out with my boat. I now have it all set with the H18 rig but have yet to sail it...hopefully that is just a week or so away. I'll let you know if I do intend to sell any/all of it down the line.

-Robert


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PostPosted: Thu Jun 25, 2020 8:13 am 
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Location: Galveston, Texas
I've heard this done before successfully, but that's a rumor. Please share how well it works. There are several H21SE's out there without masts and there are tons of 18 masts...

To the notes above - I use a mast bob no matter what, because I do NOT want to take a chance of turtling the thing in the few feet of water I sail in. Stuck in the mud = bad news...

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ChuckC
H21SE- 408


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PostPosted: Thu Jun 25, 2020 9:53 am 
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I'd post a picture but can't figure out how to insert one here.


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PostPosted: Mon Jul 06, 2020 8:39 am 
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A quick followup for anyone that may be interested. Short story is: IT WORKED. The H18 rig on the H21SE frame makes for a pretty decent combo, IMO. Sailed it this weekend in 15-20 and we had plenty of power and yet was still easy to manage. The boat felt well balanced and was really easy to sail. Tacking was also a pleasant surprise. First session had just two of us on board (combined weight of 300 lbs), the second session had four of us (combined weight of 600lbs)..and there was zero issue. It all felt like a best case scenario.


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PostPosted: Mon Jul 06, 2020 12:26 pm 
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Location: South Boardman, Mi
How did you adapt the H18 mast base to a H21 Crossbar/Mast foot?


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PostPosted: Tue Jul 07, 2020 4:42 am 
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A few more details about the setup:

Stock H18 mast with a H17 base installed in it. They are the same extrusion and the H17 uses the ball. Stock H18 shrouds were just a few inches short which was taken care of by adding a second shroud adjuster. Stock H18 forestay and roller furling. Stock H21 bridles. Sails are old style stock H18, but now that I know it works, may get upgraded to a modern square top. Stock H21 boom, but a H18 would probably work also. The H21 boom is only about 6" longer than necessary for the H18 clew. I think that about covers it. The boat itself is very solid/tight with excellent condition stock centerboards and rudders.


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