Materials for side overhang

All,


I'm considering building a side overhand for shade on a Mainship 430.... similar to what's on the MS 400.


Looking for a really strong, light weight material other than marine plywood. Nidacore, HDPE, Acetal, others??

Right now planning on it being 12 ft long, 20" wide and 4" thick, supported by bolts and a backing plate from the side panel behind the seating on the flybridge.


Pix are approximate... I'm not an artist. The first pix is from the 400.

Are you planning on any posts to hold up the outside edge?

Are you just looking for sun and rain protection or are you looking for usable deck area to store stuff on? Ir you are just looking for sun and rain protection how about a canvas solution? You can run an aluminum keder strip on the side of the bridge to seal the canvas on that side. Then a S/S frame fo hang the canvas on.

Could you make it out of solar panels on a frame?

Comodave said:

Are you just looking for sun and rain protection or are you looking for usable deck area to store stuff on? Ir you are just looking for sun and rain protection how about a canvas solution? You can run an aluminum keder strip on the side of the bridge to seal the canvas on that side. Then a S/S frame fo hang the canvas on.

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Don't want to be able to walk on (however, you could on the Mainship 400), but would like to store a kayak up there... perhaps 60 to 70 lbs max.


Mostly rain and sun.



There will be no canvas, this will be structural to a point.... just like the one on the 400. Thus my asking about a lightweight, strong material... better than plywood.

jleonard said:

Could you make it out of solar panels on a frame?

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Jay,


Great idea, but the panels would be blocked significantly by the Bimini top, so doubt that it would work. Solar will be the next project. Thx!

How about a stainless frame done with a ladder-like set of ribs? That'd give you points to keep canvas tight, so it didn't flap underway at speed, with support for paddleboards, kayak to slide along.

I'd wonder what the weight of an encased fiberglass arrangement would be in comparison?

Comodave said:

Are you planning on any posts to hold up the outside edge?

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No, they would interfere with tying up and docking.

Aluminum ladder frame bolted to the flybridge. Ridged foam panels in between the frame 'rungs' and a piece of foam bent around the outside. Fiberglass over everything. The aluminum for strength and the foam to fill in the voids. Glass to make it pretty.
Big job.

Seevee said:

No, they would interfere with tying up and docking.

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Tied into/replacing one of the rail stanchions wouldn't make much difference, the lines could still be tied as they are currently. I mean, there'd be a pole going up, but unless you're throwing lines like a rodeo it wouldn't seem like it'd matter much.

Where it would matter, though, is the expected 'shoulder space' moving along the gunwales. It's one thing to have to shimmy sideways a bit with the rails at/below waist height, but you've got your arms free to better balance/grab things to steady your walk.

That kind of grabbing force is an added reason to be concerned about how well the overhang handles weight. Someone grabbing/hanging from it would need to be taken into account for mounting.

wkearney99 said:

Tied into/replacing one of the rail stanchions wouldn't make much difference, the lines could still be tied as they are currently. I mean, there'd be a pole going up, but unless you're throwing lines like a rodeo it wouldn't seem like it'd matter much.

Where it would matter, though, is the expected 'shoulder space' moving along the gunwales. It's one thing to have to shimmy sideways a bit with the rails at/below waist height, but you've got your arms free to better balance/grab things to steady your walk.

That kind of grabbing force is an added reason to be concerned about how well the overhang handles weight. Someone grabbing/hanging from it would need to be taken into account for mounting.

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You make a good point, but just don't want those posts, they WILL get in the way, and don't believe they're needed.



I really want it exactly like the MS400, and really don't understand why Mainship didn't have these on the 430.



With our afternoon showers, it's really a PITA not to be able to crack the door open without getting soaked. With the 400, we could easily handle the boat under cover for the most part and pretty much stay dry. Looking for that.


Storing the kayak up there would be secondary, but shouldn't be an issue.



I could put a stainless "L" brace that would hold it up that would both go up the side of the flybridge side and down with another one, and would be strong enough to walk on.



Anyone work for Mainship and know how they did it on the 400?

My concern it that without the support posts there will be a significant amount of weight on the flybridge side panels. Not sure how thick they are and the panels may deform due to the weight and the leverage the panels will have on the side panels. I would look into a S/S frame with supports going down to the rails. The 400s were designed from the start to have the sides with the extension so there was structural support builtin. You are doing an aftermarket refit so you don’t have the structure there to support the weight.

Comodave said:

My concern it that without the support posts there will be a significant amount of weight on the flybridge side panels. Not sure how thick they are and the panels may deform due to the weight and the leverage the panels will have on the side panels. I would look into a S/S frame with supports going down to the rails. The 400s were designed from the start to have the sides with the extension so there was structural support builtin. You are doing an aftermarket refit so you don’t have the structure there to support the weight.

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Comodave,


You make a good point. Let me rethink that a bit..... Thx...


Another thought would be to put an angle brace like the below. Could have one angled up and one down. Would back the side with starboard, and an "H" support to the second wall (double wall) on the flybridge. That wouldn't be hard.

It was my first impression that those wings would be using the same flat platform as all the rest of the flybridge deck. But I've never seen any construction pix. I've seen some for sale listings, and a few showed what looked like a weatherstripped seam on the underside of a wing.

A search online didn't turn up any factory pix of Mainships being built. That might shed some light of someone had a video. Or if someone's done a rebuild of one due to other issues.

Most boats with flybridges don’t have much in the way of structure in the flybridge surround partly to keep weight down as well as costs. I would look it over closely before adding much weight off the surround.

I think it is totally doable the way you want using coosa board or Nidacore with appropriate layup on top. Strong, light and made to be structural. I think any glass shop should be able to hook you up easily without metal frames etc..

Maybe the frame idea and bolt UHMW to it,comes in white various thickness and would last forever

Lostsailor13 said:

Maybe the frame idea and bolt UHMW to it,comes in white various thickness and would last forever

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Lostsailor,



Good point. I need to get a bit more up to speed on plastics and determine which is the best, and can easily fabricate... cut, glue, bolt, paint, etc.


Thx!

Most of these type plastics are not easy to glue. UHMW plastic is pretty heavy. Again the weight issue hanging on the side of the flybridge surround.

I probably wouldn’t do this at all but if you want to aluminum sheet metal would be the way to go ,or a Way to go ,you could make it very light essentially like the gutter on the side of your house or heavier depending on what you have to bolted it to .very light gauge aluminum sheet . Would need to be tig welded . heavier gauge could be mig welded the metal would have to be scribed to the side of your boat to match the curve and it’s still going to look like a bolted on afterthought .Having a glass guy do it would be cost prohibitive .you have to have a place to do it .a lot of work a lot of dust good luck on your project