Need some help stabilizing a bimini top
 

Hello rec.boaters. Hope all is well and everyone is having a good
season.

Bought a Larson 22' bowrider earlier this year and had a very
enjoyable summer of cruising and water sports with family and
friends. Couple of small warranty issues, but overall she proved to
be solid and I am pleased with the boat.

However, there is one thing about the boat that is driving me nuts.
The bimini top: How it is attached to the boat, how much it flexes the
windshield at the attach points, and how much noise it makes because
of the flexing.

During any kind of chop, the bimini oscillates port and starboard, and
causes the windshield sides to flex very noticably. It's flexing
enough that I am concerned about gelcoat damage at the windshield/hull
attach points.

The bimini is a typical stainless tube structure. The base fixtures
are well attached to the gunnel (aft) and windshield frame (forward).

Here's a stock photo, and I've added a crude wireframe diagram to show
where the bimini attaches:

http://www.zjstech.net/larson/larsonbim1.gif

When deployed, two straps attach to anchor points at the corners of
the windshield.

Here's another stock photo showing the detail just inside the
windshield. The gunnel is several inches wide. The green lines
represent what I think is a logical place to put some type of support
post. I think it would look bad, breaking up the clean lines of the
gunnel, but I am at a loss for what else to do.

http://www.zjstech.net/larson/larsonbim2.gif

Getting rid of the bimini is not an option. Too much 12 o'clock sun
here in the south.

Suggestions appreciated.

Need some help stabilizing a bimini top
 

Bottom of page:
http://www.seanet.com/~jasonrnorth/bimtop6.html
JR

rbstern wrote:

Hello rec.boaters. Hope all is well and everyone is having a good
season.

Bought a Larson 22' bowrider earlier this year and had a very
enjoyable summer of cruising and water sports with family and
friends. Couple of small warranty issues, but overall she proved to
be solid and I am pleased with the boat.

However, there is one thing about the boat that is driving me nuts.
The bimini top: How it is attached to the boat, how much it flexes the
windshield at the attach points, and how much noise it makes because
of the flexing.

During any kind of chop, the bimini oscillates port and starboard, and
causes the windshield sides to flex very noticably. It's flexing
enough that I am concerned about gelcoat damage at the windshield/hull
attach points.

The bimini is a typical stainless tube structure. The base fixtures
are well attached to the gunnel (aft) and windshield frame (forward).

Here's a stock photo, and I've added a crude wireframe diagram to show
where the bimini attaches:

http://www.zjstech.net/larson/larsonbim1.gif

When deployed, two straps attach to anchor points at the corners of
the windshield.

Here's another stock photo showing the detail just inside the
windshield. The gunnel is several inches wide. The green lines
represent what I think is a logical place to put some type of support
post. I think it would look bad, breaking up the clean lines of the
gunnel, but I am at a loss for what else to do.

http://www.zjstech.net/larson/larsonbim2.gif

Getting rid of the bimini is not an option. Too much 12 o'clock sun
here in the south.

Suggestions appreciated.



--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth

Need some help stabilizing a bimini top
 

"rbstern" wrote in message
ups.com...
Hello rec.boaters. Hope all is well and everyone is having a good
season.

Bought a Larson 22' bowrider earlier this year and had a very
enjoyable summer of cruising and water sports with family and
friends. Couple of small warranty issues, but overall she proved to
be solid and I am pleased with the boat.

However, there is one thing about the boat that is driving me nuts.
The bimini top: How it is attached to the boat, how much it flexes the
windshield at the attach points, and how much noise it makes because
of the flexing.

During any kind of chop, the bimini oscillates port and starboard, and
causes the windshield sides to flex very noticably. It's flexing
enough that I am concerned about gelcoat damage at the windshield/hull
attach points.

The bimini is a typical stainless tube structure. The base fixtures
are well attached to the gunnel (aft) and windshield frame (forward).

Here's a stock photo, and I've added a crude wireframe diagram to show
where the bimini attaches:

http://www.zjstech.net/larson/larsonbim1.gif

When deployed, two straps attach to anchor points at the corners of
the windshield.

Here's another stock photo showing the detail just inside the
windshield. The gunnel is several inches wide. The green lines
represent what I think is a logical place to put some type of support
post. I think it would look bad, breaking up the clean lines of the
gunnel, but I am at a loss for what else to do.

http://www.zjstech.net/larson/larsonbim2.gif

Getting rid of the bimini is not an option. Too much 12 o'clock sun
here in the south.

Suggestions appreciated.


We have a 20 foot runabout and I installed the bimini myself. I attached
the bimini frame to the gunnel area outside of the windshield. I then
attached rubber spacers between the frame and the vertical fiberglass area
running under the windshield to the gunnel. Anchor points for the fore and
aft straps are attached to that same fiberglass area running under the
windshield.

I still get some sway in the frame (when not up or not deployed) but at
least it is not flexing the windshield as in your case.

As and easy fix you may want to put the bimini up (deployed) when running as
the forward and aft securement straps will stop the sway (at least it does
in our case.).

If you want I can post link to a pic of our setup.

Need some help stabilizing a bimini top
 

"JR North" wrote in message
.. .
Bottom of page:
http://www.seanet.com/~jasonrnorth/bimtop6.html
JR


Not relevant as I am sure he does not have a radar arch on his 22 foot
bowrider.

Need some help stabilizing a bimini top
 

On Mon, 13 Aug 2007 19:50:39 -0400, "JimH" ask wrote:


"JR North" wrote in message
. ..
Bottom of page:
http://www.seanet.com/~jasonrnorth/bimtop6.html
JR


Not relevant as I am sure he does not have a radar arch on his 22 foot
bowrider.

Why not relevant? The lateral brace doesn't care about the arch.
Probably doesn't even know it exists.

--Vic

Need some help stabilizing a bimini top
 

"Vic Smith" wrote in message
...
On Mon, 13 Aug 2007 19:50:39 -0400, "JimH" ask wrote:


"JR North" wrote in message
...
Bottom of page:
http://www.seanet.com/~jasonrnorth/bimtop6.html
JR


Not relevant as I am sure he does not have a radar arch on his 22 foot
bowrider.

Why not relevant? The lateral brace doesn't care about the arch.
Probably doesn't even know it exists.

--Vic

Your frame is partially attached to the radar arch. The arch also prevents
significant sway of the frame. ;-)

Need some help stabilizing a bimini top
 

The Arch does nothing to prevent sway, except get in the way. The
attachments of the frame to the Arch do not affect it's stability, pro
or con. Vic is right.
JR

JimH wrote:
"Vic Smith" wrote in message
...

On Mon, 13 Aug 2007 19:50:39 -0400, "JimH" ask wrote:


"JR North" wrote in message
m...

Bottom of page:
http://www.seanet.com/~jasonrnorth/bimtop6.html
JR


Not relevant as I am sure he does not have a radar arch on his 22 foot
bowrider.


Why not relevant? The lateral brace doesn't care about the arch.
Probably doesn't even know it exists.

--Vic


Your frame is partially attached to the radar arch. The arch also prevents
significant sway of the frame. ;-)




--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth

Need some help stabilizing a bimini top
 

"JR North" wrote in message
...
The Arch does nothing to prevent sway, except get in the way. The
attachments of the frame to the Arch do not affect it's stability, pro or
con. Vic is right.
JR

Your frame is inside the confines of your radar arch. It certainly does
add to the stability of the frame and prevents radical sway.

Enjoy the evening JR. I am waiting for a phone call from my son on Parris
Island.

Need some help stabilizing a bimini top
 

On Mon, 13 Aug 2007 16:26:20 -0700, rbstern wrote:

there is one thing about the boat that is driving me nuts.
The bimini top: How it is attached to the boat, how much it flexes the
windshield at the attach points, and how much noise it makes because
of the flexing.

It needs more bracing, attached to something solid. I'd make an issue
out of it with the dealer before the windshield frame breaks or is
distorted. Any good boat canvas shop should be able to give you a
quote on what is required.

Measuiriing stretch from bending tubing was Need some help stabilizing a bimini top
 

JR, since you built your own bimini frame, how did you get the width
correct when bending the tubing?
If I had a length of tubing and needed two bends, such as a bimini
frame, and I need a height of 49" and width of 88" and the tubing was of
appropriate length, where would I start the 90d bends?

John