Bimini made out of non-flexible solar cells?

[txg]

I'm currently planning how to equip our recently purchased 1978 Dufour 35 for extended cruising. Currently, the boat has no bimini and no solar. The normal way for this seems to buy an expensive canvas bimini and even more expensive flexible solar panels like the Solbian ones.

Now, my idea is to simply buy the standard non-flexible panels, for example two 140w panels and build a stainless steel frame for mounting them above the steering wheel. For me, this seems like a much cheaper and easier solution than the "standard way". Has anyone done this before or do you see any downsides to this approach?

[JK n Smitty]

This guy did that on his electric powered Nonsuch. Nice big write up about it.

[onestepcsy37]

Although I have a proper bimini I've given a lot of thought to that idea and see no reason why it cant be done. I've gone so far as to take measurements and do some drawings.

I would not use tubular bimini frames but rather flat stainless bars. Also cross pieces to reinforce the solar panel frames. And some way of keeping rainwater from dripping down on you from between the panels.

Please keep us posted.

[Alberto]

I am considering the same project for my 1975 Dufour 34. I am currently checking mounting options and hard biminis on other boats, like this one:

[UNCIVILIZED]

Originally Posted by onestepcsy37

Although I have a proper bimini I've given a lot of thought to that idea and see no reason why it cant be done. I've gone so far as to take measurements and do some drawings.

I would not use tubular bimini frames but rather flat stainless bars. Also cross pieces to reinforce the solar panel frames. And some way of keeping rainwater from dripping down on you from between the panels.

Please keep us posted.

Just a thought. You might want to use; Angle Stainless, U-Channel Stainless, or T-Bar in Stainless instead of Flat Stock. It'd give you a lot more stiffness, as well as bolting options. And or surface area to use when welding connecting pieces together.
Also, the thought runs through my head, that if it's thick enough, & stiff enough, you could use Aluminum instead. It'd be a good bit lighter, as well as easier to adapt into the design for your "back porch awning".

And as to the anti-rain angle, sealed & painted plywood would likely be fairly inexpensive. Tinted Acrylic is an option also, as is cored fiberglass (if you want to get fancy, & spendy).
Pretty much any of these could be part of an integrated structure, & not just added on extra weight. You could design it so that it had a built in rain catchment system, plumbed with hoses which terminate near your tank deck fills.

When designing it, you'd likely want to keep in mind, the idea of making it fairly simple to take apart & stow too - for when you're off of the boat for quite a while. But especially when you know that one of those storms which has names (Hurricanes) is headed your way.
So that you can delete a lot of your windage by pulling a dozen bolts, & stowing the unit's panels/high "sail area" components somewhere out of the wind.
- Thus when designing it, one would need to size the panels accordingly for this. Including the solar panels also. And not buy the monster sized ones if you want to have the option of occasionally stowing them below.

[muddyone]

Hi. I've recently done similar for a catamaran. It is more plain roof than solar panels. Also rain-catcher and mount for traveler track. So has 4 functions. Made of aluminium tubing, channel and angle stock, all bolted. Fiddly to build but quite strong. Not real pretty though

I used corrugated polycarbonate roofing sheets with low heat transmission colour. Half the sheets can be removed quickly to reduce windage and the sheets under the solar panels remain in place. The polycarbonate sheets have integral stiffness, are very lightweight and allow airflow under the panels. Downside is that they cannot be sandwiched between frame and panel easily. Polycarbonate cannot be glued easily. Manufacturers recommends suitable sealants.

For a smaller roof area I think ply as suggested would be good but I'd be glassing the top surface at least. Possibly flat polycarbonate is available. Polypropylene honeycomb may be a bit cheaper than foam core, but edges are hard to finish easily.

Maybe a breakaway sealant joint between smaller panel sections to allow for emergency removal, that can be easily re-sealed once roof refitted? There are fabrication services around that can roll rectangular tube to a radius. Not sure about the aerodynamics of that though!

[Paul L]

No reason you can't make this work well. A couple of additional comments to the ones above. You'll need a way to keep the drips from getting into the cockpit. A bimini that drips on the watch keeper isn't that useful. I second the ability to get take the panels down prior to a storm. You should design it so that shade clothes can be hung from sides and back to keep out the afternoon sun when at anchor. Also, there are many low-cost semi-flex panels now available out of China. They run about 20% of the cost of a Solbian.

[onestepcsy37]

uncivilized, I like the idea of using angle, u-channel, t-bar, and aluminum too if it's strong enough. bolting instead of welding (i can't weld). Don't like plywood. Thinking about Starboard, but it's a bit heavy and i'm not sure how i can join sections together to make a large enough 'bimini'. Hopefully, using bolts may make it easier to take it apart when necessary.

muddyone, corrugated panels are cheaper than starbrite AND would provide 'channels' to funnel water into some sort of rain catchment system. Not sure how strong they would be but worth a look.

paul l, i like the idea of shadecloths that can be dropped from the sides. could be inexpensively made with tie downs to the lifelines.

[brazenarticle]

Komocel is a sheet pvc that I used. It comes in 10mm thickness 4x8 sheets, works with woodworking tools and is much lighter ( and cheaper) than starboard.
My komocel bimini has been up for 3 years with solar panels mounted, no issues or complaints. I used ss straps to hold it to my existing ss frame.

[Randyonr3]

I'm not understanding why you would chose a Bimini made of anything other than stainless tube. Round tube is the strongest and easiest to build.
I built ours out of 1&1/4 tubing for the frame and 1 inch for the solar rack and it all bolted together.
The stainless for the bimini and solar, and the fabric was less than $300.

I've had a rogue wave break over the top of it without issues,

Its useless to purchase a quality boat for "blue water" use and then scrimp on what you add to it..

[Snore]

Randy

Looks good and practical! Where did you get the parts for the Bimini?

[Randyonr3]

Originally Posted by Snore

Randy

Looks good and practical! Where did you get the parts for the Bimini?

I scrounged......... The tubing came from ALCO , the fittings off the internet, and the fabric, "sunbrella" came from Perfect Fit. the bending was done around a couple pieces of 3/4 inch plywood glewed and screwed together..

[onestepcsy37]

Randy, my current solar panel (one 135 watt Kyocera) mount is made entirely of 1" stainless tubing and has withstood some strong winds over the past three years. I'm not certain it would be strong enough for a whole bimini top full of solar panels, but I really dont know, so I'm still "researching".

[autumnbreeze27]

We had a hard top dodger and Bimini made and are putting the flexible solar panels on it directly. I can fit 4 100 watt panels on each one. The flexible panels are lighter and less windage, and you can get them for 199 ea. I laughed at the vendors at strictly sail wanting 1200 for a similar panel.

Our tops are stainless tubing with a special starboard that is lighter than normal.

I think if you tried to make the top out of just panels you'd have a leaky tiki... All those seams to seal.

Usually its good to have grab rails on the top as well.

It doesn't sound like you care about how it will look so I won't go there

Sent from my TegraNote-P1640 using Cruisers Sailing Forum mobile app

[rwidman]

Originally Posted by txg

I'm currently planning how to equip our recently purchased 1978 Dufour 35 for extended cruising. Currently, the boat has no bimini and no solar. The normal way for this seems to buy an expensive canvas bimini and even more expensive flexible solar panels like the Solbian ones.

Now, my idea is to simply buy the standard non-flexible panels, for example two 140w panels and build a stainless steel frame for mounting them above the steering wheel. For me, this seems like a much cheaper and easier solution than the "standard way". Has anyone done this before or do you see any downsides to this approach?

If you plan on using rigid solar panels I think you need a rigid substrate to attach them to. Otherwise they will most likely flex and break. Snow or ice loads may be another thing to consider depending on where the boat will be used.

This will also prevent lowering the bimini for bridge clearance which may or may not be a problem for you. Lowering my bimini allows me to cruise under many bridges while other boats must wait for an opening.