How are travelers located on catamaran hardtops secured?

[workmaster2n]

I'm looking at a bit of a project boat, and one of the things I don't like is that the main sheet traveler is located right in the middle of the cockpit (the designer/builder was having a bit of a play with different ideas). The builder still owns the boat, and we were talking about modifications I'd make if I got the boat. I mentioned extending the hardtop to cover the entire cockpit. For reference, this is a 50 foot long, 26 foot wide catamaran with a sizable rig. So there is some power in the main sheet.

I've noticed a couple different catamarans put their main sheet traveler on the hardtop over the cockpit. Leopard, Seawind, and the Dix Harvey cats come to mind. The amount of force on these roofs must be staggering.

Does anybody know how these travelers are secured? Is it possible to build a roof that is strong enough, with perhaps an alloy plate glassed in that the traveler is then through bolted to? Or would I just be chasing a pipe dream and roof mounted travelers need to be designed from the outset?

If I go forward with this plan, I'll get a naval engineer to ensure I'm not setting myself up for failure, but before I spend the money on a naval engineer, I figured I'd ask here in case somebody had experience or knowledge in the area.

[Matt Johnson]

We have a 12mm aluminum backing plate under a large fiberglass high density cored beam. Aluminum poles on each end extends down to the bridgedeck to offer vertical support. The top itself is 1" H80 divinycell with 24oz-ish of fiberglass top and bottom.

Matt

[workmaster2n]

Originally Posted by Matt Johnson

We have a 12mm aluminum backing plate under a large fiberglass high density cored beam. Aluminum poles on each end extends down to the bridgedeck to offer vertical support. The top itself is 1" H80 divinycell with 30oz of fiberglass top and bottom.

Matt

Been following your videos for a couple years - awesome to see the progress you guys are making!

Are those aluminum poles tied into anything of significance on the deck or just glassed in to the deck?

[Matt Johnson]

Yes, they have a bolted plate onto our aft seat. But they also extend down into the seat and go into glassed pockets another 12" below the plate.

[Chotu]

That’s a good design that Matt has. i’m going to venture to say it’s better than my own. Very nice.

Basically, what you are trying to do is take care of two different loads.

First, a vertical load pulling the hard top upward.

Second, a racking load that’s trying to twist the entire roof/hardtop clockwise and counterclockwise about the mast.

If you can account for these two loads (as Matt’s does elegantly with one piece of hardware), you’re good.

I didn’t think to bring my poles down like he did. Mine are very heavily bolted to the beam with monster backing plates, but the racking load must be dealt with by wires/dyneema in my case.

[workmaster2n]

Originally Posted by Matt Johnson

Yes, they have a bolted plate onto our aft seat. But they also extend down into the seat and go into glassed pockets another 12" below the plate.

Do you have pictures or would this be in one of your videos?

[maine-cruiser]

Originally Posted by workmaster2n

Do you have pictures or would this be in one of your videos?

Don't think this shows up in any videos as of yet. If you view episode 241 where they go to Viet Nam and sail on a similar model you can see the vertical poles that he talks about.

Bill

[Matt Johnson]

Originally Posted by workmaster2n

Do you have pictures or would this be in one of your videos?

Sorry, I haven't installed mine yet. This is done on the production versions built in Vietnam (in stainless) and there may be photos online of this. Unfortunately, I looked through my photos and I don't have anything worthwhile to post.

[chrisr]

just glancing around the various cats near us, and all have the traveller mounted on the roof.

most of the modern boats have s/s poles at the aft end of the roof. we are a little different in that we have an integral fiberglass 'targa bar' that ties the roof to the rest of the boat.

this was obviously designed in at the start but i'm sure properly engineered stainless poles would do it just as well

imho your idea to extend the roof to cover the full cockpit area is a good one and something that you won't regret

cheers,