fiberglass cross trimaran

[dcamp]

I'm looking at a 1970's cross that was built with glass and foam core. I'm not familiar with this method although I like the idea of not having any wood to rot. Here's my question,how much wood is used for bulkheads , cross arms , backing plates ect.I guess the only thing thats not wood are the hulls themselves. Being 40 years old how is the structural integrity of glass going to hold up. Any help from someone familiar this type of construction would be appreciated.

[Roy M]

dcamp, where is this boat located and what is its length? I had a friend who was building a large Cross in L.A. in the 70s, but I lost track of him and the boat. It was a beautiful hull with a deep fin keel.

[dcamp]

It's a cross 38 located in Wilmington , Ca. built by Windfast marine

[Roy M]

dcamp, the boat I was familiar with was larger, about 48+ feet, it had been stretched by the owner, but Norm Cross would come out every month to check on the progress. That's where I first met him. He would always tell me it wasn't too late to convert to a Cross. It became an inside joke. Norm was a very talented designer.

As for the boat you are interested in, I assume it's a polyester resin over high density polyurethane foam. Ask the builders if they have any core samples from installing through hulls with a hole saw. That will give you a good clue as to the bonding of the inside skin, its glass thickness and lamination quality. As for the structural integrity, the Cross boats are strong in design. What type of keel does it have? If it's the fin keel, see if you can identify where the "coke bottle" depression, near the fin keel, is located. Norm used an aircraft design trick in which the fuselage has a slight depression near the base of the wing ( the "area rule"). Another "go-fast" from Norm Cross. Otherwise, it's probably the low aspect, shallow water cruising keel that many of his older boat designs featured. It's kind of like the Searunner minikeel, but deeper. Norm used to design this style for a number of Pivers and other designs as an aftermarket improvement. I installed some on Pivers back then.

If you purchase this boat, you will find out that Norm's boats don't generally have spreaders, as he preferred to run the shrouds and stays outboard. It made sheeting the jib a little tricky, but his rigs are strong.