traveler on top of bimini

[bertryane]

i was hoping to add a structural bimini that would integrate the split backstays, and also the traveler which is directly in front of the helm on a precision 28. any thoughts or anticipated pricetag? thanks

[TaoJones]

Welcome to the Forum, bertryane. Glad you're here.

About 16 months ago, I had a catamaran surveyed that I fully expected to purchase. I withdrew the offer, however, after the survey revealed the vessel had received significant damage that was the result of the mast "working" over time as the vessel completed a four-year circumnavigation. The vessel had a structural SS bimini support / traveler attachment point.

Over the course of the couple's voyage around the world, they had had to have broken welds in the structure re-welded from time-to-time. They always suspected that the dinghy davits suspended from the aft end of the structure were the source of the stresses that caused the cracks. That is, probably, at least partially true, but the surveyor and I concluded that it could not have been responsible for the other damage that manifested elsewhere.

The mast step had evidence of significant cracking, and the extent of the cracking had gotten worse over time, as someone had noted it and dated the then-extent of the largest crack more than two years earlier, and the cracking we saw was well-beyond that point.

Here's what the surveyor and I concluded had been happening:

The constant motion aboard a world-cruising vessel is virtually unrelieved, and since the boat and vessel are two separate, vitally important, components of what should be a unitary system, unwanted problems can occur if these components are moving independently. In the final analysis, it appeared that the stresses applied to the mast had been transmitted down through the traveler and the backstays, through the SS bimini support structure and into the fiberglass structure of the vessel.

In addition to the significant cracking of the mast step and the broken welds in the SS structure, there was delamination and cracking of the 'glass at the points where the SS structure was attached to the 'glass structure. At the time of the survey, there were numerous hairline cracks evident in the SS structure that were entirely unrelated to the dinghy davits.

All-in-all, it was enough to convince me that it was an ongoing problem that I would have to monitor closely, and probably spend money on constantly. But most concerning to me was the potential for catastrophic failure at some point.

None of the above may apply to what you're contemplating, but I did want to pass along my experience with one particular example of one particular brand of catamaran (Wildcat 35). Certainly what you're thinking of doing has been done countless times without any problems, so don't let my experience be anything more than a single data point.

Best of luck to you in making your vessel the perfect one for you.

TaoJones

[jzk]

What kind of Catamaran was that?

[Vasco]

Originally Posted by TaoJones

(Wildcat 35).
TaoJones

Wildcat 35, same as Bumfuzzles, maybe it was Bumfuzzles' cat.

[svHyLyte]

Placing the traveler above a "Structural Bimini" is doable but on a boat as small as a Precision 28, will make for very awkward management of the main sheet, to say nothing of the traveler itself. Moreover, the cost of the structure will undoubtedly be prohibitive.

I suspect your objective is to simply allow for a bimini which is problematic with a mid-cockpit traveler. The solution is not to move the traveler but to split the Bimini. Have a pram hood above the helm and a separate bimini, perhaps integrated with a dodger, above the forward portion of the cockpit. Underway this gives you adaquate shelter from sun/rain and good control of the mainsheet. At anchor, you can add a flap that zips into place betwee the forward and aft biminis with a slot for the mainshee in the middle, or simply run the traveler all the way outboard and avoid the slot. Below is a snap of such an arrangement although it may be a bit difficult to see well. We had such an arrangement on our old Cal 2-29 that worked very well and was relatively inexpensive.




Good Luck...

s/v HyLyte

[Gashmore]

Be very conservative if you do it. I built an FRP traveler arch on Rutu. I was a bit shocked to see how much glass had to go in it and how much structure had to be added below it when my designer sent the plans.

[Eleven]

Doing what you suggest has been a dream of mine too. It clears so much deck and cockpit space for unseasoned passengers, and for Cats it allows the rear stays to be propped away from their natural line to improve forestay tension.
The fact that nobody does it suggests that it is alot more difficult than it seems at first. On a Cat that may be worth pursuing anyway, but on a mono it's one of the many things that move people to cats.

[bertryane]

Great help all, I assumed that moving the traveler wasn't that popular for some reason. The split bimini is a great idea with at anchor flaps. How about the split backstay - think that's more feasible to integrate into the rear bimini skeleton?

[svHyLyte]

Our back-stay was split as well with an adjuster consisting of a triangular plate connected to simple blocks on either lower stay and a third block at the bottom of the plate over which a single line ran. That line was dead ended on one side of the cock-pit and connected to a 3 part tackel with a cam cleat on the other. The line and the back-stays both passed through about 3" diameter holes in either side of the the Pram Hood that had 6" high conical shaped covers that could be drawn closed around the lines/stays with a shock-cord draw string. The arrangement worked very well. (My daughter thought the cover-cones made the pram hood look like it had "ears".) Note that in addition to the flap between the fore and aft bimini, we also added a removable flap that ran between the back of the pram hood and the pushpit rails around the back of the cockpit. It stopped rain and was added protection when the sun was low in the sky.

Good Luck!

s/v HyLyte

[svHyLyte]

Below is a picture of our boat that illustrates the combination of a dodger, pram hood bimini over the helm, the rain-fly between the two and an extension between the back of the pram hood and the pushpit rails--albeit on a somewhat larger yacht absent the mid-cockpit traveler.



Cheers,

s/v HyLyte

[mmazour]

bertryane,
Did you ever get a bimini made for your Precision 28? I also have a Precision 28, hull #116, and am investigating bimini options.
Siren Song