On Wed, 15 Jun 2005 07:09:04 +0700, wrote:






On Tue, 14 Jun 2005 14:35:20 GMT, (Mic) wrote:

Much discussion deleted:

My point was the the generalization of average winds applies to very
little when considering how strong something has to be.

Good point, but to then figure that it has to be bullit proof is it
reasonable for it to be built to withstand what max force? Where do
you draw the line? That is my point.




Some years ago I was part of the team that designed and built several
oil production barges for use in the Java Sea. The design criteria for
the anchoring system was the "hundred year wave", i.e., the highest
recorded wave in the past 100 years.

Granted that was a design for a commercial vessel but when it comes to
boats I can't see much difference in pleasure boats and commercial
vessels. The highest wind I have personally encountered was in a
"Sumatra" which is a line squall common to the Malacca Straits region,
where winds exceeded 60 MPH.

As far as bimini design it might be noted that when the Sumatra hit
(at night) I had about 10 minutes warning during which the wind went
from approximately 7 MPH to 60+. I doubt that a PVC bimini wuold have
stayed with the boat -- at least in its original form.

Maybe even any bimini...
It seems less likely that a dodger will be made from ABS (abs is much
better than PVC), regardless should I build any such thing I would
certainly do my own tests first.


Cheers,

Anon
)

Mic wrote:

On Wed, 15 Jun 2005 07:09:04 +0700, wrote:

As far as bimini design it might be noted that when the Sumatra hit
(at night) I had about 10 minutes warning during which the wind went
from approximately 7 MPH to 60+. I doubt that a PVC bimini wuold have
stayed with the boat -- at least in its original form.

That's for sure.

Maybe even any bimini...
It seems less likely that a dodger will be made from ABS (abs is much
better than PVC), regardless should I build any such thing I would
certainly do my own tests first.

Actually a standard, well-designed stainless tube and canvas bimini will survive
hurricane force winds with no problem. A friend has a full cockpit cover on his
50' sailboat. The cover stays on all year. Hurricane force winds have been
logged by the instruments every winter, with no damage in 20 years.

Sometimes you do get what you pay for.

Matt O.

"Matt O'Toole" wrote in
:

Actually a standard, well-designed stainless tube and canvas bimini
will survive hurricane force winds with no problem.

I've seen power boaters test this theory on their way to the boatramp.
Some of those open biminis have been trailered over 70 MPH! Some don't
survive, however, mostly those cheap OEM ones the boats came with....(d^

--
Larry

You know you've had a rough night when you wake up and your outlined in
chalk.

Larry W4CSC wrote:
"Matt O'Toole" wrote in
:


Actually a standard, well-designed stainless tube and canvas bimini
will survive hurricane force winds with no problem.


I've seen power boaters test this theory on their way to the boatramp.
Some of those open biminis have been trailered over 70 MPH! Some don't
survive, however, mostly those cheap OEM ones the boats came with....(d^


Larry

You know you've had a rough night when you wake up and your outlined
in chalk.

Should read:

You know you've had a rough night when you wake up and you're
outlined in chalk.

It reflects badly to see gross elementary errors on a calling card.
Please fix it.

Please don't take this as criticism, I'm trying to help.

Thank you, Terry K

My dodger frame is made from fiberglass chimney rods. Flexible,
cheap, strong.

Terry K

Terry Spragg wrote:

My dodger frame is made from fiberglass chimney rods. Flexible,
cheap, strong.

It would be nice if there were an economical source of this rod mat'l
avail w/o hacking up cleaning rods, and it has many other great uses.
My chimney rod sections are only abt 3/8" or less and I don't think I'd
use that for a dodger. A set of chimney rods isn't exactly a retail
giveaway, either, and one is stuck with the unusable couplings as well
as the rather short lengths. 316L tubing in modest sizes is fairly
easy and forgiving to bend in a conduit bender (not the Harry Homeowner
type). One may even practice a little with scrap conduit to gain
confidence. I'd get the right tubing & sidle up to a commercial
electrician on a jobsite at lunchtime. At lot of these guys feel
under-appreciated & they might even bend it all up for you for free if
you've already lain it out. Remember to pickle/passivate after
finished working it all up prior covering. Unless SS is not available
in one's area, it seems a false economy to invest the planning, time,
fabric & work for a lesser mat'l.

wrote:

Terry Spragg wrote:


My dodger frame is made from fiberglass chimney rods. Flexible,
cheap, strong.


It would be nice if there were an economical source of this rod mat'l
avail w/o hacking up cleaning rods, and it has many other great uses.
My chimney rod sections are only abt 3/8" or less and I don't think I'd
use that for a dodger. A set of chimney rods isn't exactly a retail
giveaway, either, and one is stuck with the unusable couplings as well
as the rather short lengths. 316L tubing in modest sizes is fairly
easy and forgiving to bend in a conduit bender (not the Harry Homeowner
type). One may even practice a little with scrap conduit to gain
confidence. I'd get the right tubing & sidle up to a commercial
electrician on a jobsite at lunchtime. At lot of these guys feel
under-appreciated & they might even bend it all up for you for free if
you've already lain it out. Remember to pickle/passivate after
finished working it all up prior covering. Unless SS is not available
in one's area, it seems a false economy to invest the planning, time,
fabric & work for a lesser mat'l.


Chimney rods are 15 bucks each, can be disconnected and stowed, and
are a lot stronger than you might think. I used 3, with 2 ends cut
off, for my "conestoga" dodger. I do have a narrow, hinged iron
arch over the comanionway, but that's just the way it evolved.

The rods are lashed to stanctions. I may build hinges, for the after
frame, so it can be easily flopped down on deck foreward of the
companionway, but I will wait until the fabric needs replacing, so I
can cut the panels with folding down in mind. A telescoping or
folding overhead fore and aft stretcher will be required for the
collapse feature. I don't forsee needing it, the dodger is
desirable rain or shine. I need to work out a better zip out window
plan, as they shut themselves in a tailwind. With the bug net slung
over it, I have a nice gazebo to enjoy on a buggy anchorage, and it
sucks ventilation air. Sewing it herself saved the mate the price of
the materials and a sewing machine over a professional job. Stretch
the material over the frame, stick in some pins, whirrr it up on the
machine. Bob is your boyfriend. Cushion covers, next!

The rod unions are concealed beneath the wrap around zippered
fabric. The rods keep the fabric snug, flex when you hit them with
your codpiece or head, and are strong enough to grab for a handhold.
They also get out of the way when you want an inch or two for
balance, or to get the oars below, whatever.

Terry K

Terry Spragg wrote in
:

Please don't take this as criticism, I'm trying to help.



Thanks...I was in too much of a hurry and didn't notice it.

--
Larry

You know you've had a rough night when you wake up and you're outlined in
chalk.