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#1
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
Additional photos of the rebuild and refit project are now at:
http://www.pbase.com/gould/extreme_makeover Things are beginning to go back together rapidly. Bow thruster scheduled to go in next week. With any luck will be launching in two weekends. There will be a new aluminum mast and boom installed. I suppose the yard has this all figured out, but just in case,........ 1) The painted aluminum mast will be stepped into a bronze fitting. With dissimilar metals in contact there is a potential for electrolysis. Being a stinkpotter and therefore relatively inexperienced with masts, what precautions, if any, should one take? 2) The old wooden mast wasn't much of a lightning hazard, but the new mast would serve as an excellent conductor in the event of a lightning strike. Ideas for grounding? Is it important to ground it? |
#2
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
wrote in message ups.com... Additional photos of the rebuild and refit project are now at: http://www.pbase.com/gould/extreme_makeover 2) The old wooden mast wasn't much of a lightning hazard, but the new mast would serve as an excellent conductor in the event of a lightning strike. Ideas for grounding? Is it important to ground it? This is a good question and I've heard a couple of theories. The first is that a metal mast should be bonded to the boat's bonding plate to discharge a lightning hit. The problem, according to some people, is that a direct hit could carry so much current that it literally can blow the bonding plate apart, resulting in a pretty big hole in the hull. The alternative is to not bond the mast. In these cases, mucho electronics that may be mounted on it may be blow, and I've witnessed this on a couple of sailboats that were hit. My guess .... and it's only a guess ... is that the metal mast should not be bonded so well that it can carry large amounts of current. A small diameter wire that keeps the mast at ground, but would melt quickly in a direct lightning hit would be my choice. Again ... just my guess and opinion. BTW - we are down at the marina right now and I just eyeballed the work they did on the GB aluminum mast. It was corroded and chauky white last time I saw it last year. They refinished and painted it with some new type of marine paint and I swear it looks like highly waxed fiberglass. I have to find out what the paint is, but it looks fantastic. RCE |
#3
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
RCE wrote: BTW - we are down at the marina right now and I just eyeballed the work they did on the GB aluminum mast. It was corroded and chauky white last time I saw it last year. They refinished and painted it with some new type of marine paint and I swear it looks like highly waxed fiberglass. I have to find out what the paint is, but it looks fantastic. RCE If that "new paint" is ALEXSEAL, that's what we used to paint our entire hull. |
#4
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
wrote in message oups.com... RCE wrote: BTW - we are down at the marina right now and I just eyeballed the work they did on the GB aluminum mast. It was corroded and chauky white last time I saw it last year. They refinished and painted it with some new type of marine paint and I swear it looks like highly waxed fiberglass. I have to find out what the paint is, but it looks fantastic. RCE I checked up at the office. That's what they used. They've done a couple of boat hulls with it last winter and say it's the best paint they have ever used. No wonder your boat is coming out so nice. RCE If that "new paint" is ALEXSEAL, that's what we used to paint our entire hull. |
#5
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
wrote in message ups.com... Additional photos of the rebuild and refit project are now at: http://www.pbase.com/gould/extreme_makeover Things are beginning to go back together rapidly. Bow thruster scheduled to go in next week. With any luck will be launching in two weekends. There will be a new aluminum mast and boom installed. I suppose the yard has this all figured out, but just in case,........ 1) The painted aluminum mast will be stepped into a bronze fitting. With dissimilar metals in contact there is a potential for electrolysis. Being a stinkpotter and therefore relatively inexperienced with masts, what precautions, if any, should one take? 2) The old wooden mast wasn't much of a lightning hazard, but the new mast would serve as an excellent conductor in the event of a lightning strike. Ideas for grounding? Is it important to ground it?\ Thanks for the update and photos! Hope to see the boat in person on the water sometimw! Dan |
#6
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
wrote in message ups.com... Additional photos of the rebuild and refit project are now at: http://www.pbase.com/gould/extreme_makeover Things are beginning to go back together rapidly. Bow thruster scheduled to go in next week. With any luck will be launching in two weekends. There will be a new aluminum mast and boom installed. I suppose the yard has this all figured out, but just in case,........ 1) The painted aluminum mast will be stepped into a bronze fitting. With dissimilar metals in contact there is a potential for electrolysis. Being a stinkpotter and therefore relatively inexperienced with masts, what precautions, if any, should one take? 2) The old wooden mast wasn't much of a lightning hazard, but the new mast would serve as an excellent conductor in the event of a lightning strike. Ideas for grounding? Is it important to ground it? Looks like she will be a beauty Chuck! |
#7
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
Harry Krause wrote:
wrote in message ups.com... Additional photos of the rebuild and refit project are now at: http://www.pbase.com/gould/extreme_makeover Things are beginning to go back together rapidly. Bow thruster scheduled to go in next week. With any luck will be launching in two weekends. There will be a new aluminum mast and boom installed. I suppose the yard has this all figured out, but just in case,........ 1) The painted aluminum mast will be stepped into a bronze fitting. With dissimilar metals in contact there is a potential for electrolysis. Being a stinkpotter and therefore relatively inexperienced with masts, what precautions, if any, should one take? 2) The old wooden mast wasn't much of a lightning hazard, but the new mast would serve as an excellent conductor in the event of a lightning strike. Ideas for grounding? Is it important to ground it?\ Thanks for the update and photos! Hope to see the boat in person on the water sometimw! Dan Nylon bushings and washers. Harry, This seems like a great and easy solution, but I would question the strength and longevity of the bushing and washers, both from stress fatigue and UV degradation. I know they have made advances in nylon and plastic but I still would be leery of this w/o follow up by some experts. I don't know the answer, but if this was a viable long term solution, I would think it would be standard on new sailboats. Chuck, I can be guilty of over engineering a solution, so I only have to do a project once, but I would contact sailboat and trawler mfger's or even your boatyard (you must have a lead or two) and ask for their recommendations. My ignorant uneducated solution would be to separate the two problems and solve each separately. I would see if quality caulk to keep water and oxygen away from the dissimilar metals would be a viable long term solution. Then use a lighting dissipators at the top of the mast to reduce the risk of lightning. http://www.fourwinds-ii.com/lightning/lightning.htm I have always liked the look of a classic trawler and this will turn heads on the water. |
#8
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
Reginald P. Smithers III wrote:
Harry Krause wrote: wrote in message ups.com... Additional photos of the rebuild and refit project are now at: http://www.pbase.com/gould/extreme_makeover Things are beginning to go back together rapidly. Bow thruster scheduled to go in next week. With any luck will be launching in two weekends. There will be a new aluminum mast and boom installed. I suppose the yard has this all figured out, but just in case,........ 1) The painted aluminum mast will be stepped into a bronze fitting. With dissimilar metals in contact there is a potential for electrolysis. Being a stinkpotter and therefore relatively inexperienced with masts, what precautions, if any, should one take? 2) The old wooden mast wasn't much of a lightning hazard, but the new mast would serve as an excellent conductor in the event of a lightning strike. Ideas for grounding? Is it important to ground it?\ Thanks for the update and photos! Hope to see the boat in person on the water sometimw! Dan Nylon bushings and washers. Harry, This seems like a great and easy solution, but I would question the strength and longevity of the bushing and washers, both from stress fatigue and UV degradation. I know they have made advances in nylon and plastic but I still would be leery of this w/o follow up by some experts. I don't know the answer, but if this was a viable long term solution, I would think it would be standard on new sailboats. Chuck, I can be guilty of over engineering a solution, so I only have to do a project once, but I would contact sailboat and trawler mfger's or even your boatyard (you must have a lead or two) and ask for their recommendations. My ignorant uneducated solution would be to separate the two problems and solve each separately. I would see if quality caulk to keep water and oxygen away from the dissimilar metals would be a viable long term solution. Then use a lighting dissipators at the top of the mast to reduce the risk of lightning. http://www.fourwinds-ii.com/lightning/lightning.htm I have always liked the look of a classic trawler and this will turn heads on the water. I hope you know I mean YOUR BOAT will turn heads, not the lighting dissipator. |
#10
posted to rec.boats
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More rebuild and refit photos, grounding the mast?
On 11 Jun 2006 10:13:19 -0700, "
wrote: 2) The old wooden mast wasn't much of a lightning hazard, but the new mast would serve as an excellent conductor in the event of a lightning strike. Ideas for grounding? Is it important to ground it? The mast should definitely be grounded, preferably in several different ways. By doing that, the mast behaves much like the lightning rods on a building, bleeding off accumulated charge before it builds into a full strike. That said, sailboat masts still get hit very frequently, and damage to electronic equipment is not uncommon. At dock or anchored, very large sailboats frequently hang zinc "fish" from the rigging wires into the water to provide additional protection. I do that with our GB49 here in south Florida where thunderstorms are an almost daily event during the summer months. Not sure if it really helps, but it feels like I'm doing something proactive. |