Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?

Bob Swarts

On Sun, 16 Oct 2005 08:01:04 -0700, Robert or Karen Swarts wrote:

Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?

Bob Swarts

There could be weight and righting moment issues.

Maybe it will be OK, but I guess I would at least want to do the math
before I poured the foam...

There could be possible corrosion problems.

Hollow masts are pretty resistant to oxidation. If you fill it with foam
it could easily develop pockets of poor drainage, and therefore corrode.

--Mac

On Sun, 16 Oct 2005 08:01:04 -0700, "Robert or Karen Swarts"
wrote:

Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?

Bob Swarts


Hmmm...why foam fill?

If wood, it might preserve from water damage....
If metal, might dampen halliard slapping noise....

Or is there some other purpose - not strength, I don't think

Brian

I would guess it all depends on YOUR defilation of 'foam'.

When this question comes up there are usually references to ' . . .pouring
foam . . .'. I would absolutely NOT use any of the 2-part 'Pour-in-Place'
foams. Your are really in it, as regards solutions to 'What if . . .?'
problems.

What I think of in this situation is the foam 'Swim Noodles' or big blocks
of Styrofoam. Cut to roughly 'rod shape' about the ID of the mast. Just
shove them into place with a long piece of 1x1 or lengths of 1in PVC.

The reasoning behind ANY foam or flotation material is to fill AIR SPACE. It
is the AIR that gives the actual buoyancy. That's why they designate the
'Marine' foam as '2 pound', '3 pound', etc. That means that for each cubic
foot, the foam weighs 2 pounds, etc. Therefore, when calculating buoyancy .
.. . a cubic foot of water {there is a slight difference between Salt and
Fresh}weighs about 62 pounds MINUS the weight of the foam EQUALS the ability
to support 60 pounds per cubic foot of that particular material.

Regards & Good Luck,
Ron Magen
Backyard Boatshop

"Robert or Karen Swarts" wrote in message
...
Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?

Bob Swarts

I give up ... why would anyone fill a mast with "foam"?

"Robert or Karen Swarts" wrote in message
...
Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?

Bob Swarts

Primary reason is that it increases righting moment in the event of a
capsize. I suppose it might also keep the mast from sinking in case of a
demasting.

Might make the mast marginally stronger if completely filled.

I also misspoke in this area in that what I was envisioning was plugging the
mast with foam rather than completely filling it.

BS

"Bowgus" wrote in message
...
I give up ... why would anyone fill a mast with "foam"?

"Robert or Karen Swarts" wrote in message
...
Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?

Bob Swarts

Robert or Karen Swarts wrote:

Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?


About the only foam you would ever consider placing inside a mast would
be blocks of soft furniture foam for the purpose of quieting any wires
inside the mast that might be slapping the mast.

IMHO, the result is almost the biggest PITA on the planet.

Been there, done that.

A good messenger cable makes the problem go away.

Lew

On Sun, 16 Oct 2005 15:39:19 -0700, "Robert or Karen Swarts"
wrote:

Primary reason is that it increases righting moment in the event of a
capsize. I suppose it might also keep the mast from sinking in case of a
demasting.

Might make the mast marginally stronger if completely filled.

I also misspoke in this area in that what I was envisioning was plugging the
mast with foam rather than completely filling it.

Bingo...

An inversion may cause the mast to fill with water, and depending on
the diameter and lenght of mast, the the leverage weight at or near
the masthead would be significant. I think 1square foot of water is
about 64 lbs. Or about 1 gallon of water is about 8lbs...

Anyone know what the leverage force would be needed to lift 64lbs at
30ft of leverage from the folcrum point? That may not be exactly the
right question...

I would not recommend filling the complete void in the mast, but
sealing of the mast might be considered. As this was a suggestion by
someone making their boat 'bluewater' ready as just one of the things
they would do.

Also if the mast is buoyant then it could help the righting momentum.

BS

"Bowgus" wrote in message
...
I give up ... why would anyone fill a mast with "foam"?

"Robert or Karen Swarts" wrote in message
...
Assuming one makes provision to access and mechanical or electrical
components within the mast, are there any compelling reasons NOT to foam
fill the mast?

Bob Swarts

I did it because I was going insane from the constant chiming noise
something inside the mast was making snip styrofoam peanuts.
Bob Swarts


That makes sense ... and I suppose foam would have solved that particular
noise problem. A very long application tube would be required initially I
would think, to be withdrawn as the mast was filled, to ensure complete
filling.

But "Rob or Karen" did then say just to plug the mast. Home Depot here sells
what's called Hotstuff (I think) foam in aerosol cans for home insulating
.... but I don't know that it would provide the desired waterproof/airproof
seal. Easy enough to find out though I guess ... plug the mast, head out to
deep water and chuck the mast overboard ... "Rob or Karen" ... let us know
how that works out :-)

Locally at least, it's called "Great Stuff." Be advised that it is
incredibly sticky (wear disposable gloves) and that it continues to expand
slowly, with significant force, for weeks after it's applied. It is
waterproof and airtight.

I don't think I'd use it on a mast except maybe for plugs at each end. Less
is better.

Once you've used part of a can, it's really difficult to come back later for
a second task, kinda like 3M 5200 except the problem is the plugged
applicator tube and valve. The solidified foam turns brown and crumbly when
exposed to sunlight for any length of time.

Roger

http://home.earthlink.net/~derbyrm

"Bowgus" wrote in message
.. .

I did it because I was going insane from the constant chiming noise
something inside the mast was making snip styrofoam peanuts.
Bob Swarts

That makes sense ... and I suppose foam would have solved that particular
noise problem. A very long application tube would be required initially I
would think, to be withdrawn as the mast was filled, to ensure complete
filling.

But "Rob or Karen" did then say just to plug the mast. Home Depot here
sells
what's called Hotstuff (I think) foam in aerosol cans for home insulating
... but I don't know that it would provide the desired waterproof/airproof
seal. Easy enough to find out though I guess ... plug the mast, head out
to
deep water and chuck the mast overboard ... "Rob or Karen" ... let us know
how that works out :-)