Prisma composite hull beams are constructed from fiberglass with a non-woven polyester backing; 2 PCF flotation grade polyurethane foam. Suited for applications including stringers, fuel tank supports, large fiberglass structures, panel size reduction in hulls.
Common installations usually only require a simple, three-step process. Wet out the underside of each Prisma beam, position them where desired, wet out the top side of each beam, roll the tabs, and you're done. Prisma preforms saves time, material, and labor costs on just about every installation.
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Sold in 4ft lengths.
Base Width (A)
Top Width (C)
Tabs and Base (D)
Suggested Applications: Stringers; Fuel Tank Supports; Large Fiberglass Structures; Panel Size Reduction in Hulls
Use only with marine epoxy, polyester or vinylester. Proper surface preparation prior to installation is critical to achieving structural integrity. Follow the resin manufacturer's directions
Failure to keep PRISMA products dry and clean prior to installation can decrease the structural integrity of this product.
Prisma Composite Preforms
I have a section of keel that needs to be replaced on a 13' Whaler. I have purchased this product for other uses and it worked great. As it stands, the product is much too tall and wide to set in and replace the damaged (removed) section. I would have to trim it both for height and width but it intrigues me because it is long and straight and, if trimmable, would perhaps work great for the missing keel segment. Can the glass be completely peeled off of the Prisma foam and then the foam be trimmed down to the dimensions I need, and then the glass be reattached?
I suppose you could but seems like a waste, would be less expensive to just use foam and fiberglass cloth.
JD Tech Team
When installing this composite stringer system, can you cut them down for height towards the bow of the boat? I am tearing out rotted wood in my 1982 Sunset Center Console and want to go all composite. Stumbled upon your site and it may be a life saver. Also, do you or can you recommend composite boat deck/floor. I want NO WOOD in my boat. Means NO ROT. LOL Thanks
You could lift up the cloth and cut down the foam to shape. Take a look at Core-Cell A550 Plain Foam Sheets for deck replacement.
JD Tech Team
I would and will pruchase again if needed...
I have a 2004 Sea Pro SV2100 which, I think, is a great boat. The boat is all composite and is built solid. The only problem I have is that the compartment...deck lids/hatches...are not reinforced very well; ie have some flex in the larger ones like the large lid on the front deck and the larger live well on the back deck. Anyhow, I was racking my brains on what to do and knew that using a marine grade plywood or Kingboard was an option but would definitely add some unwanted weight to the boat. Well, I came across there thru some internet searching along with some Youtube post and gave Jamestown a call. They were very helpful and knowledgeable in regards to this product. I have never fiberglassed in any way, and hoefully the picture does the work justice, but I think it turned out great. I took the large front deck lid off one morning, sanded it, mixed the EPOXY resin and hardener (West Systems) and within a few hours in the Texas sun it was done. The very next morning (yesterday) my brother and I went out and with him pushing 280lbs it did not budge...no flexing at all... It would previously show some signs of flexing with as little as 175lbs to 200lbs. Anyhow, I know I'm rambling on but I am very happy I went this route. These are lightweight and are easy to install. Do not underestimate the strength of this product.