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Steve Lusardi
 
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Brian,
I applogize for the misspelling and brain fade. I knew it was wrong, but
sent it anyway.
Marc,
Stephen Baker's reply is spot on. Do not use inadaquate materials. On my
boat I have a 12" wide steel plate the runs all around the deck that is
welded to the steel hull on the outside and on the inside it fastenens to a
steel space frame design that supports the teak deck. Under each of the 30"
stanchions, which are made of prepolished 1.25", 316 SS tubing, I used 1.5"
x .250" SS carraige washers. Through which I run a single 3/8 x 16 cap screw
threaded to welded nut plates at the bottom of each stanchion. My logic was
to support the base of the stanchion with a single screw, because at the top
of the stanchions I have a continuous run of the same prepolished tube all
welded together for stiffness. In addition, I have 3 runs of 6mm SS wire
equally spaced, through the stanchions around the boat. The wire terminates
with rigging screws at the pushpit and supports netting and spray protection
cloths at the cockpit. This sounds very stiff, but it isn't. There is a
maximun of 3" of in/out motion at the rail, in the center of the boat. It is
however, very strong. The single screw is designed as the rail failure
point, rather than the deck and it works as designed. I had the mast
horizontally above the deck, supported at the bow and stern by 6 x 6 beams
holding a cover over the deck. In a 70 mph gale, the 6 x 6 supports failed
and the mast fell. The rail deformed at the collision points and 2 stanchion
mounting bolts broke, but the rail held the mast and all the attached debris
without any deck damage.

In your FG case, the same solution would work, but I would recommend the use
of backing plates to spread the load at the deck level. The use of tubing
for stanchions fastened with a single bolt is weak by itself, but coupled
with tubing at the top and the SS wires tieing all the elements together as
a common structure, is easily strong enough to capture and hold a 200 lb man
in a collision. Additionally, the slight give at the rail will absorb a
considerable amount of energy, which could significantly reduce injury in a
mishap.
Steve

"Brian Whatcott" wrote in message
...
Since you asked for input, Courtney, here's mine:
the word stanchion is undeserving of being respelled.

Happy Christmas!

Brian.

On Fri, 24 Dec 2004 18:56:28 -0500, Courtney Thomas
wrote:

Steve,

I'd appreciate hearing about stantions you'd recommend.

What do you think of 3/4" galvanized pipe ? If so, what size flange
would you use ?

Thanks,
Courtney



Steve Lusardi wrote:

Marc,
The problem with your solution is that would not survive a 200 lb body
collision in a storm. You have strengthened the stantion mount for sure,
but
not sufficiently. The problem is with the FG. It is a low density
material
and is incapable of holding that force with only 3 square inches of
support.
Your solution needs at least 5 or 6 times more support. Consider the top
of
your stantion as a lever point. How much torque would you be applying to
the
base? Your solution has only improved the deck's ability to absorb
fastener
compression. You will require very large backing plates under the deck
as
well. I would use 1/4" stainless plates 12" long and as wide as possible
bonded to the underside with 3m 5200, as fasteners will not hold in FG.
Even
at that, the stantions I see advertised are only good for decoration.
Steve

"Marc" wrote in message
...

I am replacing the teak handrails with stainless steel. My intent is
to eliminate teak maintenence and create a strong point in the deck.
To that end I have core drilled a 2" dia hole from underneath
(leaving the top skin intact) at each rail attachment point. This has
removed the wet core. In order to eliminate overhead work, I intend
to make a layup on my work bench 1/2" thick and then cookie cut out 2"
discs and epoxy these into the empty core location at each rail
attachment point. Once these are in place, I'll fill any low points
and glass patch the bottom skin. The rail, itself, has captured nuts
at each attachment point and will be thru bolted from underneath with
large backing plates.

Question: What layup schedule should I use for the cookies?

So far, I have prepped for one rail and I have three more to go.
Question: Is there an easier way to do what I want to do?