Making hard Coach Roof/ Bimini - questions

[valhalla360]

Originally Posted by carlosproa

My bad on explaining. I am not saying that I will use a layer of FG, I am saying there is a choice of prepegged FB material sold. From there, I can always add layers.

My point was not about the number of layers of fiberglass but the effect of shape.

Once you have enough layers to avoid point penetration of the surface, modifying the shape of the cross section is usually more effective than just throwing more layers at the problem.

[carlosproa]

If you look at the new Mainecat38, it appears they are going away from having just a hard top with vinyl zip sides to having partial hard sides and front with some kind of sliding window upfront to pass into the net area. There are enough Al posts strategically placed to address load bearing issues. They use thermo bent foams with vynilester. I am on the fence of having or not hard sides and front. The Aventura sport catamarans also uses this type of layout. I have time to mull this over before I pull the trigger. I will let you guys know if I decided to do it
As always thanks for all the advice

[smj]

https://svzingaro.com/2016/12/28/how...your-sailboat/

[smj]

https://youtu.be/WJSAdZTollc

[Pete7]

Are you planning some sort of guttering so the rain doesn't drip all over anyone stood just outside and will a fresh water catchment area be needed with down pipes to tanks?

Will there be heavy solar panels mounted on top?

Pete

[carlosproa]

I have not made a decision about water catch. Is a weekend boat so it sits in the mooring daily. Need to think how to make sure water tanks are not overfilled. I am sure there is a clever way to route the hose so after reaching capacity it overflows out.

I will relocate two solar panels to this top.

[Kudu]

IMHO, do-it-yourself major mods on a production boat are a good way to destroy value. Better to sell to somebody who appreciates the original design, and buy something that works for you and yours.

[Michael Pope]

Sorry! I personally think you guys are way to light for a 16 foot span. if this is going to be walked on . Let alone have a wave break over it. Go talk to a good Naval Architect.
I would be using at least 1.5 inch core with at least 36 ounces per sq Yd Glass Bi material and epoxy on the bottom surface and may be a little lighter on the top face but not less than 24 oz Glass on the top face . Also a good substantial 3 inch plus square section beam front and back., The trouble I see is if you make it lighter and it breaks it will fall and completely prevent you from doing anything swift about getting rid of it so you can sail on! I am not familiar with the vessel maybe I am missing something Mike P

[kryg]

After years of checking out coach roof I found one I would like to have fabricated as my boat is Aluminum as well. The problem in Sydney Aust.,is finding the talent to build it at a a price that is less than the cost of a down payment on a house.





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Originally Posted by carlosproa

Greetings from Miami

I have and EDELCAT33 that has served me well but the Admiral does not like the center pod, too hot and claustrophobic for her.

For those not familiar with EDELCAT33, is 3 separate structures and is demountable
dodger 2.jpg Views: 156 Size: 87.3 KB ">Attachment-IRJDSUNE9932123321222xxeww-201561

So I am thinking of getting rid of it and make a hard coach roof like a Mainecat 38 or 41. My thought is to have Aluminum posts and build the hard to out of either foam Divinycell or Nida-Core Honeycomb. The latter has the option of having pre-laminated with 1 layer of 18oz woven roving in either side with polyester.

The coach roof or hard top would be roughly 8 ft long by 16 wide.
My question is which thickness to get so if I have to walk on top, it would hold. They offer 1/2, 3/4, 1 inch.

Looking at the new Maincat38, I see they use hard sides instead of the zip up vinyl they normally do

Any thoughts?

[CarinaPDX]

Search around for other threads on this subject. Most notably there is this one: http://www.cruisersforum.com/forums/...ps-175159.html but there are others as well - a lot of info out there.

Greg

[coopec43]

[QUOTE=kryg;2998095]After years of checking out coach roof I found one I would like to have fabricated as my boat is Aluminum as well. The problem in Sydney Aust.,is finding the talent to build it at a a price that is less than the cost of a down payment on a house.

Attachment 201630[/QUOTE

I think you'd find it would be a lot cheaper built in fiberglass. You are right in saying you find it hard to find the talent. But they'd need to have the equipment as well (eg rolling machine)

The dodger I like (Garcia) is along the lines of your favorite. (Riada11 looks great too)

Dodgers
Outbound, Garcia, Cross Marine, Riada11

[JohannDW]

I have just completed a an 18 square metre bimini in foam and epoxy. Also with support only at the extremities. Used 25 mil foam with glass and epoxy, 5 layers top and 4 below. The weight of the glass is important and a good supplier will also be able to advise you. Routed for the downlighters and other wiring. I added a few wide 'ribs' at the top, and these have stiffened the structure even more. I used marine ple insets, with glass between, for the attachment points. All seems very rigid, and is quite light.

[dennismenace111]

Take a look at this video....The young man in the video has an older catamaran that needed a hard top. It will give you a good idea of what it takes and how he went about it. Hes a pretty talented guy when it comes to repairing and fabricating stuff for his boat.

https://www.youtube.com/watch?v=WJSAdZTollc

[carlosproa]

Thanks for all the advice. I follow him and the Zíngaro guy also. I think I have enough information collected. Will let you know if or when I pull the trigger. Need to find time to do thdi

[madprops]

Originally Posted by JohannDW

I have just completed a an 18 square metre bimini in foam and epoxy. Also with support only at the extremities. Used 25 mil foam with glass and epoxy, 5 layers top and 4 below. The weight of the glass is important and a good supplier will also be able to advise you. Routed for the downlighters and other wiring. I added a few wide 'ribs' at the top, and these have stiffened the structure even more. I used marine ple insets, with glass between, for the attachment points. All seems very rigid, and is quite light.

I would love to see photos, I'm close to starting my hard top build.