Suggestions for Hard Dodger Construction Please

[DennisDW]

Greetings from St. Petersburg, Fla. It's full on summer and it's just too hot to day sail so I'm on to my projects.

I will be building a hard dodger for my Cambria 44. I have some experience with fiberglass part fabrication but I'm no pro. I would like the advice of those who are.

I want a full fixed dodger with hard top. I'll be mocking up the design in 1/4" ply to get the styling and dimensions down. I just haven't decided how I want to build it.

I certainly could make a female mold and lay it up with a foam core. I could build it out of marine ply in a stitch and glue format. I could use a high density core like Coosa board. Or maybe something else? I plan to use spray Awlgrip or equivalent as a finish and forego gelcoat- I think. I'm just not sure. I need a plan.

What do those of you who do this for a living think?
Dennis.

[Terra Nova]

I think the Cambria 44 is one of the most beautiful boats. It should be your first priority to NOT destroy the boat's good looks.

Method of construction should probably be based on your own building skills. I've built hard dodgers from wood and aluminum; one circumnavigated. It can be helpful to first create conceptual design sketches on photocopies of the boat's photo, trying various approaches to see how they look.

[zboss]

Ill be following this thread closely, as I was thinking a hard dodger and top would be great on my Cabo Rico. I'd be interested in the styling to see what you think looks good and is functional.

Maybe a lowish cantered top with teak stripping... something to match the swoop of deck.

[sailr69]

seek out a product designer, a skilled one. properly done , it will be a easily accomplished project.

[Stumble]

On a crusing boat I would use solar panels to replace a fabric biminie, failing this foam core composite boards would be my first choice.

[SkiprJohn]

Member Celestialsailor has done a few and the ones I've seen were very well built. He had a few photos on the forum with "how to" information which I can't seem to find while searching. If you try the search functions it should come up. I just can't find it.

kind regards,

[Nicholson58]

Originally Posted by DennisDW

Greetings from St. Petersburg, Fla. It's full on summer and it's just too hot to day sail so I'm on to my projects.

I will be building a hard dodger for my Cambria 44. I have some experience with fiberglass part fabrication but I'm no pro. I would like the advice of those who are.

Dennis.

Whatever you decide, I recommend US Composites as a source for epoxy (635 THIN resin and any fillers, glass carbon etc. you need. I will never use any other, base on a lot of experience. Fiberglass , Epoxy , Composites, Carbon Fiber - U.S. Composites, Inc.

[minaret]

Originally Posted by zboss

Ill be following this thread closely, as I was thinking a hard dodger and top would be great on my Cabo Rico. I'd be interested in the styling to see what you think looks good and is functional.

Maybe a lowish cantered top with teak stripping... something to match the swoop of deck.

If you camber the dodger top to match the deck camber, it will look flat due to optical illusion. You need more camber than the deck has, or it won't look right. This is a basic rule of boatbuilding.


I'd mock up in doorskin, build in Coosa, glassed in place rather than mechanically fastened. Then finish with gel so you can blend all around for that factory look, rather than the after market bolt on look. Only way I do it.

[Terra Nova]

58--nice job on the dodger. The polished window frames came out well. And the curves make it truly part of the yacht.

[DennisDW]

Thanks for all the good advice. That's a nice job on that dodger! I know that a clunky appendage is an eyesore on any boat and I hope to enlist the original designer's eye in getting it right. I'll let folks know how it's going.
Cheers,
Dennis

[robert sailor]

A friend of mine built a real beauty using multiple layers of door-skins covered with glass. It was attached with s/s pillars at the sides and he used a heavy plexiglass attached in an aluminum u shaped extruded fitting attached to the hard top and the deck. He installed wiring for lites and mounts for solar panels. He did a first rate job., Like another poster suggested he mocked it up just using a single layer of doorskin but decided once he got the shape just the way he wanted it he just added more layers, easy peasy....well not really, long project actually.

[Terra Nova]

Door skins are commonly assembled with interior glue. They are fine for making patterns and mock-ups, but not for boat building.

[minaret]

Originally Posted by Terra Nova

Door skins are commonly assembled with interior glue. They are fine for making patterns and mock-ups, but not for boat building.

Also too thin to route internal wireways into before glassing.

[Nicholson58]

Originally Posted by zboss

Ill be following this thread closely, as I was thinking a hard dodger and top would be great on my Cabo Rico. I'd be interested in the styling to see what you think looks good and is functional.

Maybe a lowish cantered top with teak stripping... something to match the swoop of deck.

Here are pictures of my cous's Rico. Does this help?

[OceanSeaSpray]

Lots about the look of it, little about the way to build it! Dodgers rarely improve the look of a boat indeed... Draw it on top of a photo for a start for example.

In response to your actual question, I would use Divinycell foam core, 20mm thick in H60 grade (60kg/m^3). This is quite a standard spec for making hulls, wheelhouses etc. I have designed boats with this material and I have used a lot of it in the workshop as well. It is great stuff to work with and it lasts forever provided you do a proper job - more further down.

For a one-off hard dodger, you should be able to make a timber framework and "bend" the foam panels on it, rather than making moulds. Tie them through with plastic cable ties or similar, glue all your edges, sand them round once everything is set and glass the outside first.
After that, it will be dimensionally stable and you should be able to cut the cable ties flush, remove the mould and glass the inside.

I would do it in E-Glass/polyester as there is no benefit in using more expensive resins for something like this. Three layers of 450GSM woven roving and as little CSM as possible should give you a strong and light structure.
If you are going to fasten equipment to it and you already know where, you can replace the core with a small piece of marine ply for example, or glass one side, cut the core away from the other side and glass more heavily in the cavity etc. Standard stuff. With window cut-outs, you will have to remove/replace the core along the edges if you use through fasteners.

For curved panels especially, it is often better to glass the full panels and cut any windows afterwards. I use a simple jigsaw with a small metal blade (like a hacksaw blade). The glass in the laminate will dull it immediately, but it will keep working almost forever.

Now, most important piece of advice with foam cores: vacuum very carefully the core surface to remove all dust, wet it with resin, give it 10 minutes, make sure you get all the air out of the pores, wet it again and then lay your pre-cut glass cloth etc.
If you try to wet through or do anything else, you won't get a proper bond onto the core and this is how everything later delaminates.

Happy boatbuilding.