Sun shade or bimini for bridge deck

[HeadedToTexas]

The aft bridge deck of our Mariner 37 (Helmsman 38) is sunny and inviting, but calls out for shade as the day heats up or the exposure begins to burn. I am trying to decide on the best approach for an easy to deploy, easy to store solution.

I found a suitably sized right triangle sun shade of matching blue material. The two aft rod holders could be fitted with aluminum poles to support the long corners with the short or middle corner attached to the mast. There would be sufficient clearance and plenty of shade for people sitting in deck chairs.

Alternately, I could build a folding bimini frame to mount on the bridge deck rail. The bridge deck is 12’ wide and measures 76” between the mast and aft rail. The geometry escapes me, but it feels like there is a design that could allow an aft bimini to shade this area when up and store against the aft rail when down. What do you guys think?

 

[Choices]

I see sport fishermen using Spinnaker material to make a light weight shade that attaches to the stern or poles in rod holders.

I would guess they roll it up when not in use.

 

[Comodave]

How about putting 2 more rod holders forward so you can put 4 poles in the rod holders. Then put a pulley on the top of the poles and a jamb cleat on each pole. Then a lightweight piece of canvas with 4 lines that go through the pulleys to the jamb cleats. Pull the lines tight and cleat them off. Quick to put up and quick to get down. Also will stow easily with 4 loose poles and some folded up canvas.

 

[FWT]

Seems to me one unanswered question is, do you plan to have it up when underway, or just at the dock? Underway would call for something more substantial. Just at the dock opens up options for something more lightweight and easier to stow.

You might start cheap and easy and see how it goes. You can get more more advanced later if experience says you use it. A lightweight fabric / nylon tarp with grommets in the corners in the approximate size you want would be the first thing to locate. It shouldn't be expensive. 4 poles, and lash it to the poles. The poles can be lashed to the rail, or those rod holders. I favor lashing it the rails just because any slight breeze can catch that sail and lift it out the holders. When ready to stow, just fold the 4 poles against opposite sides of the tarp so they are parallel, and roll.

Sag in the middle will be an issue to solve too

Not a bad idea to try.

 

[AlanT]

The aft bridge deck of our Mariner 37 (Helmsman 38) is sunny and inviting, but calls out for shade as the day heats up or the exposure begins to burn. I am trying to decide on the best approach for an easy to deploy, easy to store solution.

I found a suitably sized right triangle sun shade of matching blue material. The two aft rod holders could be fitted with aluminum poles to support the long corners with the short or middle corner attached to the mast. There would be sufficient clearance and plenty of shade for people sitting in deck chairs.

Alternately, I could build a folding bimini frame to mount on the bridge deck rail. The bridge deck is 12’ wide and measures 76” between the mast and aft rail. The geometry escapes me, but it feels like there is a design that could allow an aft bimini to shade this area when up and store against the aft rail when down. What do you guys think?

We had the same situation. We installed SS poles in the aft corners of the upper deck. We went with SS because of the tension in the lines needed to cover the 20+' from the aft roof of the bridge-deck to the stern. We decided to have the cover only cover the part that we would actually use ~10' to reduce weight and stress, and were able to find cheap (~$150) material for the sunshade (from Amazon)which we are evaluating for longevity. Its early days (installed 7/2021). So far we are extremely happy with the shade and increased usability.
https://www.trawlerforum.com/forums/members/4000-albums1132-picture6962.jpg
https://www.trawlerforum.com/forums/members/4000-albums1132-picture6961.jpg
https://www.trawlerforum.com/forums/members/4000-albums1132-picture6959.jpg

 

[NWSeadog]

Something that you might want to consider is using shade cloth rather then a Sunbrella type of product. We use shade cloth and it is very light weight and easy to string up. It comes in different densities and still lets wind through (somewhat). Shade cloth is typically used around green houses.

 

[HeadedToTexas]

Great ideas. This is definitely an at slip only shade. The material I have in mind is this item. My solution for securing the aft two poles in the rod holders is to pass a bungee through a hole in each pole that loops over the bottom of the rod holder. If that proves too stretchy, it could be replaced by a short line that could be tied in place.

https://www.amazon.com/gp/product/B01N4N4960/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

 

[AlanT]

Great ideas. This is definitely an at slip only shade. The material I have in mind is this item. My solution for securing the aft two poles in the rod holders is to pass a bungee through a hole in each pole that loops over the bottom of the rod holder. If that proves too stretchy, it could be replaced by a short line that could be tied in place.

https://www.amazon.com/gp/product/B01N4N4960/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

We initially looked at triangular shades, but after testing we found that the coverage was insufficient - unless the sun was pretty much directly overhead. We lose around half the coverage of our rectangular shade at the times we usually sit out (4-7pm) and a triangle reduced the coverage to one chair!

Here is what we went with:

https://www.amazon.com/gp/product/B08N9PNKKB/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

They come in all sizes and I ordered the one with scalloped sides which stays perfectly stretched with no creases.

Looking at your avatar, and given that you only would use it at anchor you might consider attaching it to the aft of your existing bimini using cord that is long enough to get past your mast (sort of the reverse of what we did - see photos).
~A

 

[HeadedToTexas]

Beautiful execution, Alan. That's very much what I'm after. My challenge is that we have no rigid structure to which to attach the forward corners, and our mast stands right in what would be the middle of that space. We looked at the geometry of the right triangle and it definitely loses coverage, but it is more than adequate for our needs. At least that's our take at this point in the planning.

 

[AlanT]

Beautiful execution, Alan. That's very much what I'm after. My challenge is that we have no rigid structure to which to attach the forward corners, and our mast stands right in what would be the middle of that space. We looked at the geometry of the right triangle and it definitely loses coverage, but it is more than adequate for our needs. At least that's our take at this point in the planning.

Thanks! I edited my comment after sending and added this text which may help your thought process:

"Looking at your avatar, and given that you only would use it at anchor you might consider attaching it to the aft of your existing bimini using cord that is long enough to get past your mast (sort of the reverse of what we did - see photos)."
~A

 

[HeadedToTexas]

One reason the right triangle works for us is that our slip puts the stern south and that is where the wide beam of the long side of the triangle hangs.

 

[Gdavid]

I would look for a mesh fabric so you don't have to worry about leaving it up in the rain. They are heavier to begin with but would avoid damaging your supports if a shower catches you by surprise.