I would like to pump out the ballast before pulling my 26s up the ramp. Does anyone have any suggestion regarding type, brand, model # ect.for a pump that can do the job.
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Bob Cassel, Mac 26S, SF Bay
Don't pump it out, pump air in...
What you need is an air toy inflation pump from WalMart for about $12. You can get 12 Volt, rechargable or ones that run on D batteries, any will work. PUt a hose on the end of it that will fit snugly into the air vent hole. Open the air vent hole and the fill valve, plug the hose into the air vent hole and start the pump. In about 10 to 15 mintues the air will fill the ballast tank pushing the water out the fill hole. You'll know becasue you will have bubbles coming up along one side of the boat. Close the fill valve and shut off the pump. You're done. There will still be some water in the tank, about 3 to 5 gallons, but that can drain out later as you go down the road.
What you need is an air toy inflation pump from WalMart for about $12. You can get 12 Volt, rechargable or ones that run on D batteries, any will work. PUt a hose on the end of it that will fit snugly into the air vent hole. Open the air vent hole and the fill valve, plug the hose into the air vent hole and start the pump. In about 10 to 15 mintues the air will fill the ballast tank pushing the water out the fill hole. You'll know becasue you will have bubbles coming up along one side of the boat. Close the fill valve and shut off the pump. You're done. There will still be some water in the tank, about 3 to 5 gallons, but that can drain out later as you go down the road.
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Peter Vaas
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Dave M26D
Doesn't take much
pressure, the 26C will empty with about 1psi, what you want is a low pressure/high volume air pump like those sold for inflating toys. Don't know if it will speed up the rate while moving, probably will.
pressure, the 26C will empty with about 1psi, what you want is a low pressure/high volume air pump like those sold for inflating toys. Don't know if it will speed up the rate while moving, probably will.
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AndyS
I wonder the same thing as Randy
The inside surface area of the ballast tank is going to be significant - and the tank is designed to hold water, not pressure. Say, for example, the tank was 8' long, 2' wide, and 4" deep (internal measurements) - that would make the surface area of the top side of the tank all by itself 2,304 square inches (96" x 24"). Even at 1 psi, that is 2,304 pounds of total force being applied outward from inside the tank. In fact, with a high volume, low pressure inflation pump, and your ballast valve fully open, you probably wouldn't even reach 1 psi effectively because the outflowing ballast water is acting as a "relief valve". However, if someone was to close the ballast valve when the tank was about half full (full surface area of the top side exposed inside), I would think you could build up dangerous pressure inside. On large ships, when taking on fuel (or water), there are specific rules for how much incoming pressure you can have based on the size of the air outlet vent on the tank - I have seen the results of a few large tanks that were filled too fast or filled with the air vent secured - the results were, shall we say, "spectacular". I'm not necessarily saying I would not try this method, but I would be extremely cautious about making sure the outlet remained open and free of obstructions. - AndyS
The inside surface area of the ballast tank is going to be significant - and the tank is designed to hold water, not pressure. Say, for example, the tank was 8' long, 2' wide, and 4" deep (internal measurements) - that would make the surface area of the top side of the tank all by itself 2,304 square inches (96" x 24"). Even at 1 psi, that is 2,304 pounds of total force being applied outward from inside the tank. In fact, with a high volume, low pressure inflation pump, and your ballast valve fully open, you probably wouldn't even reach 1 psi effectively because the outflowing ballast water is acting as a "relief valve". However, if someone was to close the ballast valve when the tank was about half full (full surface area of the top side exposed inside), I would think you could build up dangerous pressure inside. On large ships, when taking on fuel (or water), there are specific rules for how much incoming pressure you can have based on the size of the air outlet vent on the tank - I have seen the results of a few large tanks that were filled too fast or filled with the air vent secured - the results were, shall we say, "spectacular". I'm not necessarily saying I would not try this method, but I would be extremely cautious about making sure the outlet remained open and free of obstructions. - AndyS
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Dave M26D
Total force is irrelevant
pressure is force per unit area. The hull will easily withstand 1 lb/sq.in. The total pressure necessary to evacuate the ballast tank has nothing to do with the depth of the tank. What you are trying to overcome is the depth of the water above the valve outside the boat. In the case of the D it would be 14". At first, with the tank full, lower pressure is needed, but as the differential between the level in the tank and the outside height of water increases, more pressure will be required(of course as the tank empties, the boat becomes more buoyant and that affects the differential). Using a pump that produces significant pressure might certainly cause a problem. But the low pressure toy pumps are safe and have long be employed by 26C owners to accomplish the task.
pressure is force per unit area. The hull will easily withstand 1 lb/sq.in. The total pressure necessary to evacuate the ballast tank has nothing to do with the depth of the tank. What you are trying to overcome is the depth of the water above the valve outside the boat. In the case of the D it would be 14". At first, with the tank full, lower pressure is needed, but as the differential between the level in the tank and the outside height of water increases, more pressure will be required(of course as the tank empties, the boat becomes more buoyant and that affects the differential). Using a pump that produces significant pressure might certainly cause a problem. But the low pressure toy pumps are safe and have long be employed by 26C owners to accomplish the task.
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AndyS
Dave ...
Sorry, I guess I was not clear - but the salient point I was trying to get across was that as long as the ballast valve remains open, the pressure should not be an issue. Close that valve, apply a few PSI inside the tank, and you may cause a crack in a weak seam or spot. I always fear someone like Tim Taylor on "Tool Time" saying "Well, if this little air pump empties the tank in 15 minutes, then the 100 PSI from my buddy's portable compresser will empty it in 3 minutes!" ("More power, Tim!) - and proceeding to split a big seam in their ballast tank. I never used depth in my simple example - in fact if you wanted to figure depth into it, you'd have a differential equation based on the rate of change of the water depth versus the increasing surface area as the water goes down. I was also just using one of the six sides of a theoretical tank, to illustrate how quickly the force of the air pressure (surface area) could build up. Regards, AndyS
Sorry, I guess I was not clear - but the salient point I was trying to get across was that as long as the ballast valve remains open, the pressure should not be an issue. Close that valve, apply a few PSI inside the tank, and you may cause a crack in a weak seam or spot. I always fear someone like Tim Taylor on "Tool Time" saying "Well, if this little air pump empties the tank in 15 minutes, then the 100 PSI from my buddy's portable compresser will empty it in 3 minutes!" ("More power, Tim!) - and proceeding to split a big seam in their ballast tank. I never used depth in my simple example - in fact if you wanted to figure depth into it, you'd have a differential equation based on the rate of change of the water depth versus the increasing surface area as the water goes down. I was also just using one of the six sides of a theoretical tank, to illustrate how quickly the force of the air pressure (surface area) could build up. Regards, AndyS
Blow da water!
Great discussion......I think for 12$ and the fact that we all agree if the valve is open, this can be done safely...also, I did not know 26D owners had done this for a long time.....I knew it had been discussed, but sounds proven.......I think I will try this....under way....I don't know about sitting in my slip and blowing the tanks.......... 4 4
Great discussion......I think for 12$ and the fact that we all agree if the valve is open, this can be done safely...also, I did not know 26D owners had done this for a long time.....I knew it had been discussed, but sounds proven.......I think I will try this....under way....I don't know about sitting in my slip and blowing the tanks.......... 4 4
I doubt it could hurt the tank...
even with the valve closed. You have to remember that these pumps are high volume/low pressure. They're not like a piston or diaphram compressor, they would have a hard time popping a cheap air mattress, so there's no way they're gonna develop enough pressure to rupture the fiberglass ballast tank! If you're really concerned about over-pressuring the tank, install a pop-off valve set at 1 psi in the hose fitting and problem solved.
even with the valve closed. You have to remember that these pumps are high volume/low pressure. They're not like a piston or diaphram compressor, they would have a hard time popping a cheap air mattress, so there's no way they're gonna develop enough pressure to rupture the fiberglass ballast tank! If you're really concerned about over-pressuring the tank, install a pop-off valve set at 1 psi in the hose fitting and problem solved.
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Bill at BOATS 4 SAIL
Water Ballast Pumpout Warning
A serious concern I have is if the ballast tank is partially filled. When the ballast tank is completely full or empty, the boat is stable. If the ballast is partially emptied, the center of gravity can change quite rapidly, making the boat very unstable, and not self-righting.
A serious concern I have is if the ballast tank is partially filled. When the ballast tank is completely full or empty, the boat is stable. If the ballast is partially emptied, the center of gravity can change quite rapidly, making the boat very unstable, and not self-righting.
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Dave M26D
That is a fact
for the 26C, the original question pertained to the X...a different animal. The C is very unstable with an empty tank and trying to sail it with a partially filled tank is inviting disaster. Blowing the tank on the C is best done tied up, just before loading on the trailer.
for the 26C, the original question pertained to the X...a different animal. The C is very unstable with an empty tank and trying to sail it with a partially filled tank is inviting disaster. Blowing the tank on the C is best done tied up, just before loading on the trailer.
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