Follow up on command bridge biminis

[Yolodin]

Pre purchase research: I previously posted question on biminis for 2018 29 ft RTCB . Thank you Shane, who had outfitted with a 4 bow - 84” . My canvas guy ask about ‘ moment arm’ problems with either the 4 bows or 3 bows . Essentially the effect of the the top heavy Bimini on stability of boat while underway … appreciate hearing your experience and if you have pics of open and close Bimini that would also help

 

[ShaneM]

I haven't noticed a difference in the stability of the boat due to having the extra weight of the bimini up on the CB. That said, it has likely been offset by all the weight we've added closer to the waterline (tools, spares, provisions, gear, oversized dinghy and motor, etc)!

If we're not using the bimini, it sits flat along the railing which reduces the moment arc. If we're using the bimini underway, I'm at the upper helm which results in considerably more weight up on the bridge (I'm not a small guy). Add in the rest of the family if they come up to the command bridge and the weight of the bimini is trivial.

The bimini does act as a sail when the breeze is blowing. Not a problem at anchor but it can contribute to rocking and rolling at the dock if we're broadside to the breeze. More than once I've woken up in the middle of the night when a strong cross breeze has come in, and had to drop the bimini to reduce the roll and the noise.

 

[Yolodin]

I haven't noticed a difference in the stability of the boat due to having the extra weight of the bimini up on the CB. That said, it has likely been offset by all the weight we've added closer to the waterline (tools, spares, provisions, gear, oversized dinghy and motor, etc)!

If we're not using the bimini, it sits flat along the railing which reduces the moment arc. If we're using the bimini underway, I'm at the upper helm which results in considerably more weight up on the bridge (I'm not a small guy). Add in the rest of the family if they come up to the command bridge and the weight of the bimini is trivial.

The bimini does act as a sail when the breeze is blowing. Not a problem at anchor but it can contribute to rocking and rolling at the dock if we're broadside to the breeze. More than once I've woken up in the middle of the night when a strong cross breeze has come in, and had to drop the bimini to reduce the roll and the noise.

Thanks Shane. Great information!

 

[ShaneM]

Typically, biminis are installed with the main bow angled aft around 45 degrees. We flipped ours around so that it could lie flat because our boat shed is too short



This shows the main bow forward, with vertical struts to anchor it to the railing. The secondary bow is aft with struts angled in to provide lateral stability.

 

[Yolodin]

View attachment 26830
Typically, biminis are installed with the main bow angled aft around 45 degrees. We flipped ours around so that it could lie flat because our boat shed is too short

View attachment 26831

This shows the main bow forward, with vertical struts to anchor it to the railing. The secondary bow is aft with struts angled in to provide lateral stability.

Thanks for pics . Helpful Ken