Since this thread is locked in the archives

[Ross]

I shall continue it as a new thread. There was some discussion about the use of canned foam to plug the mast. It seems like such a good idea that I really wanted to be able to make it work. The problem is that it isn't self supporting until it cures. Also it must have atmospheric moisture to be able to cure. So I put myself to work on how and today I drilled a 5/8 inch hole in a piece of 4 inch pvc pipe and pushed about eight inches of the leg of a stocking into the hole, I had tied the inside end closed and stuck the foam tube into the open end and into the pipe and dispensed away . The foam squeezes through the mesh but stays with the stocking. Almost none dropped out the end . I shall have to wait to see how it cures.

 

[Don S/V ILLusion]

Ross - won't that trap moisture?

nm

 

[Jadedcrew]

Keeping Rainwater out of the Bilge

If I remember correctly it was Joseph Shirley's idea to keep rainwater coming down the mast out of the bilge. You will need to provide a drain at the top of the foam (hoping that it is flat so as not to trap puddles) to allow the water to get out at that point, somewhere on deck. That will be a constant spot that will need tending to keep it clean. Currently rainwater from the mast is the only source of water in my bilge, and I would rather have it there than running down the cabin top leaving a trail all the way to the closest drain over the edge. My bilge (C36) is not real deep, and easy to sponge out any water that gets in.Interestingly, I removed most of my halyards for cleaning this winter, and only had small (1/8") messengers in place of the halyards. Each time I checked there was little or no water in the bilge. As soon as I put the halyards back in I started getting more water with a storm.In my opinion it is a hair braind idea, but I am Jaded.

 

[Ross]

Response to the concerns , There is no way to keep it flat on top.

It you have internal halyards this will trap them . I think that it would stay wet. In all of my work I try to keep water out at the source and try to never trap it. The foam expands like yeast bread dough and is not controllable inside the pipe. I think that this idea is a bust.

 

[Don S/V ILLusion]

sounds like foam in the mast

would cause far worse problems and is like treating the symptom rather than the problem. I'd be more concerned with moisture in the mast than water in the bilge.

 

[Ross]

Don , I had a home owner complain to me

once that he had water dripping out of the porch ceiling whenever it rained and he asked if I could caulk those leaks and stop the drip. I refused and told him that we needed find out how the water was getting in and stop it there. He didn't like the price for some roof repair. I don't know what he finally did.

 

[jackhartjr]

Ross, I have not researched...

...the canned foam. However a lot of folks doing bus conversions have done the spray in foam thing for insulation and found the heat from the two chemicals reacting would warp the sides of the bus. Some have sprayed it in between the skin and a panel and found that if too much foam...it puches out on the sides. I doubt that the canned foam would get hot enough or dense enough to cause damage to the mast. Just wanted to throw that out there.Jack

 

[Dan H]

I think there is more to it than just foam

In Richard Henderson's book, Understanding Rigs and Rigging, he describes a process for sealing the inside of the mast. He writes that once the foam is in place, a rubber seal is poured on top of that. He does this through the lowest halyard exit. With the boat healed, he pours the rubber up to the bottom of the lowest halyard exit. He heals the boat so when the boat is up right, the rubber slopes toward the exit to drain the water. The original poster, I believe, had in mast furling, and that might be a different kettle of fish.

 

[sailaway78]

Rain water in the bilge

I think there is some mis comprehension here, at least as far as my past posts were concerned, with regard to plugging the mast. I never had any intentions of plugging the entire mast. My initial inquiry was pointed towards sealing up the sail track, not the entire mast. What I have is a sail track, that I assume from looking at it, is pressed into a groove/slot on the mast. It has a 5/8 opening, which is where I believe the water is coming in. This track ends just below the gate, and from there down, the groove/slot is covered with a pressed in insert. This insert is fairly flush with the outside of the mast. It is my belief that the rain water blows into the mast track, and from there runs down behind the insert, into the bilge. There appears to be nothing to stop water flow from continuing down behind the insert, into the bilge. The foam was just one idea, and was posted up here for your approval/ disapproval/ comments. This is a little easier to get to than I had origionally thought, and to check out my theory, I am going to stuff some plumbers putty in there before it rains again. IF this is successful in slowing down the water intrusion, then a more permanent solution will be decided upon. But right now some closed cell foam seems to be the best solution.

 

[Dan H]

Maybe I am Mis-comprehending

But I assumed Ross was refering to John's post Labeled "Water Entry through Roller Furler." 4/11/08.Sorry for the confusion.

 

[sailaway78]

I had kind of jumped the thread

Dan, I had kind of jumped in on the origional thread. But I do see some similarities. Will be on a friends boat in a couple of days that has a roller furling main, and will look and see if they are similar in the design of the track, and where the water is coming from on the roller furler.

 

[Joseph Shirley]

Ross, I'll watch for your final review

If the foam expanded like it has in the past for me, it should have a dome top when it's cured. A drain hole in the vicinity of that dome should drain all but maybe a thimbleful of water that should evaporate. That much water inside a mast is no more than what stays in there now. Since it's closed cell foam, it should be water tight so a rubber cap, or a slope, shouldn't be necessary, but it doesn't sound like a bad idea.BTW this is a foam plug only, 4 to 18" high, that will plug the mast from maybe as low as somewhere below the deck, to just above the deck and below the halyard exits. It will capture the wiring that goes all the way down the mast, but it will not trap the halyards unless they exit and run below deck.Mick, if you are concerned about rainwater that might run down the inside of your mast staining your deck, what do you do about the rainwater that runs down the outside of your mast; or is the inside that much dirtier than the outside? But then again what do you suppose people do with deck stepped masts, pump them out? no, the just let the internal water drain out the base right onto the deck. For you though, I guess it is just a hair brained idea, so don't do it, but if you haven't tried it, don't knock it.I congratulate Ross for giving it a try. The stuff is so sticky though, that i believe you could have gradually closed up the area by doing just a little at a time, letting it expand and cure, and adding just a little more and so on, instead of using the leg of stocking, but any way that works to completely seal the ID is OK.And Don, the problem is a hole in the boat (the inside of the mast) that lets water in. We solve the problem by plugging the hole. How is that treating the symptom? Good LuckJoe S

 

[Ross]

Joe S. The foam has expanded to its limits and has formed

the typical dome. I think that finding the lower top edge might be tricky. But drilling a hole and working a probe upwards until you struck water would be enough. I have used this foam for many off label purposes. Built my icebox with extruded styrofoam and canned foam. Lined it with fiberglass and epoxy. Built up some pontoons for outriggers for a sailing canoe the same way. I am sure if you were patient you could plug the tube with little shots of foam but it is hard to check your progress.Have a pleasing day.Ross

 

[Maine Sail]

Just one question..?

If you have a keel stepped mast, as I do, and the mast wiring exits near the base of the mast, how do you propose the foam will seal around each and every wire if it's in a stocking?Personally, I prefer a mast base sump that contains the rain and fog water not allowing it into the general bilge. I have this on my boat and it's very easy to dry out after a rain as it's contained.. I'll eventually need to re-wire the mast and getting a large chunk of expanding polyurethane foam out of my mast, that is six feet up inside, is more of a PITA than I think it's worth. I have used this stuff around the house and it is a pain in the neck to remove! It's basically Gorilla Glue or 5200 in a foam version...Please, for your own good, do not fill your mast at the deck level with Great Stuff! Trust me it won't be so great when you need to do mast work....

 

[Paul Brinkley]

General info on polyurethane foam

Years ago, I worked for a company that built refrigerated truck bodies. About 90% of them were insulated with urethane foam. The walls of these trucks were foamed in place- that is, they were built with the exterior panels and interior panels attached to a frame; then the expanding foam was poured into the wall cavity from the top and allowed to expand and fill the wall cavity. Since these walls were from 3 to 5" thick, a considerable amount of foam was involved. Before foaming, the body interior panels were covered with large flat panels which were braced against the panels on the opposite walls. Then large, heavily braced structures were rolled up to all exterior sides of the body and clamped across the body. This was necessary to keep the wall panels from bulging as the foam expanded. Once the foam cured, all of the bracing was removed. The process does generate some heat. However, the heat never presented a problem to the panels, which were steel, aluminum, or fiberglas-reinforced plastic just like our boats. The pressure was what had to be controlled. (Jack Hart- I doubt that heat was really what warped the bus sides- it was more likely the pressure.) Some of the advantages of the foamed in place truck bodies: 1. better insulation than the equivalent thickness of fiberglass batts, 2. fewer voids- expands to fill any cavity, 3. because the foam sticks to everything it touches, it bonds the body frame, the exterior panels and interior panels together into an extremely strong and rigid assembly.As for other uses of the foam- its almost like duct tape- adaptable to some really strange things. When my kids were in high school, all 3 went through 4 years of band, and my wife and I were band boosters for 14 years. I got to build a lot of props for the band's half-time shows. For a space theme one year, I built a Star Destroyer (the triangular ship from the Star Wars movies) that was 26' long, 9' high, and 12' wide. One person could carry it around- it was made from sheet styrofoam building insulation and held together with Tuff Stuff polyurethane foam, because that was about the only thing that would glue it together and harden permanently and quickly. Built lots of things with styrofoam sheets and Tuff Stuff: medieval castle, Egyptian temple, pyramids, etc.There should be no problem using it to plug a mast. As Ross says, you can always drill or poke a hole or holes through the foam to drain the water.-Paul

 

[Paul Brinkley]

Maine Sail-

Wiring run through the foam would be a problem. However, it is not necessary to put in a large quantity of foam. If I had your situation with the wiring, I would not use the stocking. I would use small shots and make as short a plug as I could, no more than about 2" thick. Without the stocking the foam would seal around the wires. Should it become necessary to replace the wiring, it would not be that difficult to break out the wires from the plug. Where there's a will, there's a way... ;D -Paul

 

[Jim]

Why canned foam in the mast is a bad idea

One you'll never get a wire run through it.Two you could trap water in the mast that could freeze and cause damage.Three when you sell the boat the new owner will curse you 1000 times which may cause you to get cancer.

 

[Ross]

I don't have the problem of a keel stepped mast

so I can't claim knowledge about the problems associated with such an arrangement. But I think that about 8-10 feet of conduit would solve the problem of getting wire past the plug. Also anyone who thinks that they could make a 2 inch thick plug in a pipe, working blind, in a vertical pipe, has probably not used many cans of great stuff foam. The piece of stocking I used was indeed about 8 inches long but only about half was pushed through the hole. The foam expanded through the mesh in the knit but was held in position so enabling a one shot filling.

 

[John]

Just now

I'm just now reading this thread because I hadn't realized it pertained to my issue. Yes, as one contributor wrote, I have in-mast furling and a keel stepped mast. I think this enables a lot more water to drain down into the bilge than in boats without in-mast furling. (If I had my choice, I don't think I'd opt for this type of set-up. It's just that the boat came with it.) And it's not just rain water; when waves wash up over the deck, then a lot of sea wager goes down the mast. I've been in touch with Charleston Spars, who apparently are the manufacturers of this mast. To be certain, I have to e mail them a photo, and after that, if it's theirs, they say they may have some suggestions. I, personally, am pretty hesitant to try Ross's solution as it may have some unintended consequences and I think it would be a huge problem to try to get the foam back out again.

 

[Stillraining]

Irwins all came

from the factory with a conduit run for the wiring so they would not be an issue...The possible freeze dammage to us northern sailors would keep me from trying it...In principal I like the idea..but would not want to risk it..If there was some way to blow up a balloon in the mast that could be deflated in the winter..I might go for that...Hay maybe there is my million dollar invention...Keep away from it Ross & Main...