fiberglass dodger build with no core?

[Matt Johnson]

Originally Posted by Mg451

Saw a very nice dodger build on you tube never seen any one build one with no core be just used 1708 (2 layers). I'm looking to build a dodger and bimini as light as possible. I think this guy's is one of the nicest I've seen and looks pretty easy since I have a soft dodger and can use them patterns. Know it's not super strong but it's gotta be stronger the a canvas dodger. I'm thinking of duplicating this build and just looking to see if any one has seen one done this way and had any input. I've done alot of glass work using 1708 so I know what's involved..

https://youtu.be/Mi2gtvd6hBM?si=dSKuoVV2BtxVkbHD

Here's the link..

Two layers of 1708 is way too thin for any solid fiberglass dodger. Any time someone leans against it, it will bend, crack the glass and further weaken the top. Even a 3/8" core will do wonders to stiffen the structure.

You could go down to a lighter cloth on each skin, but then you'd have the issue of the surface being easy to dent. I'd do two layers of 12oz biaxial--same overall cloth weight as one layer of 1708, but uses less resin and will be stiffer.

Home Depot foam does not have the sheer strength to work in this application. You need a proper coring PVC or PU foam. If you're not close to a supplier, order from a place that will cut a sheet down to an easily shippable size. The foam pieces can then be reconnected with thickened resin on the butt joint with no real loss of strength.

[Mg451]

I suspected it was to weak (2 layers of cloth) did you see the part where he bent it though? It took a hell of a bend and alot of force to do so. I'll prob core it with corecell. But really liked how easy fast and nice looking this build is

[barnakiel]

Cored uncored seems more like a technology thing. Cored can be built lighter and stiffer per same weight - and will also be cooler (tropics) and more quiet (rain).


I like the Youtube one very much - except I woul like my dodger to be deeper - to cover more of the side - at least the part in the corner up front where I hide from any sudden wave invasion when beating and on close reach/beam reach.


b.

[Nicholson58]

I suggest you hunt around YouTube videos for how to. Be creative on search parameters.

Carbon fiber instead of glass is tremendously stronger. I made this spinnaker launcher for my Tornado about 20 years ago using only two layers of two-ply carbon stitch mat. Very high drapability, easily forms to compound curves. This was formed over a silicone rubber covered, shaped foam plug. Plug removed and neat resin used to smooth the imperfections. I can stand on this thing and not deform it a bit.

Make the dodger and then add rectangular strips of foam to the inside. Use epoxy and reinforcement materials to close the box.

[s/v Jedi]

Putting in a core is impossible for this construction method. You need it as flexible as required to bend it in shape much like canvas.

With a core, you create a stiff panel. People replying here do not understand the concept. Two layers of 1708 is much stronger than the Sunbrella it replaces so any point of critique gets the reply that it is better than the traditional dodger.

I liked his work. The stainless tubing doesn’t rust anymore than it does inside canvas (and only iron rusts, stainless steel corrodes which is black) and it is much more durable.

I don’t like the bolted windows though and also think he made the wrong material choice there: polycarbonate will have a much shorter lifespan than acrylic. Also, the edges of the windows are exposed which is a no-no as the UV radiation entering there will be traveling all the way through the material as the surfaces reflect it back inside like fiber optics work. The edges should be painted as well as a rim of the outer perimeter to protect the VHB tape against UV (and hide the bolts)

[Mg451]

Yes jedi i think the point was missed about it not being a "hard" dodger just better then the canvas. I think it looks pretty simple and quick build

I've never used carbon fiber cloth wonder how this would turn out with carbon fiber cloth rather then 1708 or biaxel