Expandable Foam as Mast Wedge

[sneuman]

Wondering if anyone has ever tried this. To me it seems idea, as the stuff form fits and is solid as a rock once cured.

Thoughts?

I am talking about the stuff in a can you can get from Home Depot, etc.

[edsailing]

The problem would be if you wanted to pull the mast later.............

[sneuman]

Originally Posted by edsailing

The problem would be if you wanted to pull the mast later.............

Yeah, I thought of that, but if I put plastic on the mast and around the partners, it would allow one to pop out the foam later, I would think. Worst case would be to cut the stuff out.

[iiii]

No, the problem is it only works for a while. Movment of the mast causes it to leak after a while, then you have to dig it out.
Don't ask!

[sneuman]

Originally Posted by iiii

No, the problem is it only works for a while. Movment of the mast causes it to leak after a while, then you have to dig it out.
Don't ask!

Leaking isn't an issue, as there will be a mast boot for watertightness. Will it lose its strength over time too?

[edsailing]

Shouldn't degrade to much if not exposed to UV. I guess the question is, What do you have against conventional methods e.g. wedges?

[S&S]

Great Stuff and the like doesn't have sufficient conpressive stregnth to hold up. I wouldn't recommend it.

[s/v Jedi]

Sneuman: it will not stand the compression forces over time, but that's something for an experiment: if you have that 2-component mix&pour foam, you can make some test-batches using disposable molds (plastic cups) and try different formulations. One would be the foam alone, another one add microballoons (I read they improve foam compression characteristics with microballoons) and try other fillers like microfibers and even colloidal silica or pieces of rubber. After cure, test with equal compression.

Another thing: pour the exact quantity so that you can keep the skin of the cured foam intact.

But the perfect pourable mast wedge exists already of course but it's pricey...

cheers,
Nick.

[sneuman]

Good to know all this. I think rather than experimenting, I'll go with something tried and true.

[Vasco]

A friend of mine made his own similar to Spartite. Some sort of two part rubber. Spartite was much too expensive.

[John A]

Rainwater will enter the mast from the top of the mast and over time will create enough weight to create an upside down pendulum. After removing the mast and digging out the foam to run the wiring thru PVC pipe, I found that I almost never sailed with the rail in the water, as I did on numerious occasions before. The halyards are external.

The foam was installed by the previous owner and was unditected upon purchase.
John

[GordMay]

SparTire 2000 Mast Wedge Replacement System has a compressive strength of 55,000 PSI, a tensile strength of 4,000 PSI;
whereas
a 16 Lb. High-Density 2-part expanding urethane foam might have a compressive strength of about 750 PSI, and a tensile strength of about 450 PSI.

16# is a VERY high density foam, and doesn’t come anywhere near to the strength of SparTite.

[S&S]

Originally Posted by John A

Rainwater will enter the mast from the top of the mast and over time will create enough weight to create an upside down pendulum. After removing the mast and digging out the foam to run the wiring thru PVC pipe, I found that I almost never sailed with the rail in the water, as I did on numerious occasions before. The halyards are external.

The foam was installed by the previous owner and was unditected upon purchase.
John

Inside? What was the guy thinking?

[s/v Jedi]

Originally Posted by John A

Rainwater will enter the mast from the top of the mast and over time will create enough weight to create an upside down pendulum.

Ah, but you are talking about foam inside the mast. You can do that but need to have drain holes just above the top of the foam. This is how our water-stop works just above deck level.

cheers,
Nick.

[cabo_sailor]

I have Spartite and have been very pleased with it. As Gord says, I can't imagine that any foam that would not start compressing within a short time allowing the mast to move about. Internally for silencing wire slap - sure. Externally where it has to take all stress of a mast trying to move - no. I'd use traditional wooden wedges first.

Rich