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Discussion Starter #1
Does anyone know how heavy the centerboard is on our boats? I know I need to make it negatively buoyant but was wondering how much weight I need to put in it.
 

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Discussion Starter #4
Should have mentioned the boat, duh! It's a North American/Spirit 23 CB. Shoal keel with a centerboard. Hmm, I am wondering how to get 50 lbs of weight in there! It's not huge, but I was hoping to use cedar strips to glue something up and not sure how I would add that much weight.
 

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formerly 'BoatyardBoy'
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Mine is hollow, at least I think it is from tapping on it. It doesn't fall on its own, I have a rope tied to the bottom of the board.

What I was going to do was haul it out, drill a inch or so hole in the side at the top and if there isn't any foam in it, I'm going to pour some lead shot in it. Hoping to get at least 30 - 40 lbs. Then pour resin in it to keep it still. Glass the holes back up.

-sent from sea via corked bottle
 

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sunfish?junior?
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Please make sure you are dry before you pour ! lead and even a small droplet of water can get ugly. Dry the area out completely. With a heat gun or any other dry heat source, Let us know how it goes.
Best wishes, Lou
 

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formerly 'BoatyardBoy'
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I don't follow... What does water and lead have to do with anything?

I was going to pour/spray acetone in it to clean it out for the resin to stick a little better so I imagine the water will be gone by then.

-sent from sea via corked bottle
 

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formerly 'BoatyardBoy'
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Do you mean water as in if I'm pouring molten lead in there? I'm pouring lead shot, basically BBs or shotgun pellets. They will flow in there.

-sent from sea via corked bottle
 

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I am guessing mine weights around 50lbs , I do have a piece broken off the bottom .
You're right about the weight if your talking about the lead in the bottom part only. The reason only the bottom has lead & the rest is fiber/foam is so that the board will remain down without being held and it can still swing up if it hits anything. I had to rebuild mine & when I did I epoxied & screwed a stainless rod & plate on the lower leading edge & bottom so I can test the rocks on the sea bed with no damage. I do that sometimes. It works great but makes you jump when you don't know the test is coming!
 

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If you guys think you can pour molten lead in a foam centerboard and your going to do it...please please post some pictures!
I would not advise it though. Seriously buy some lead shot from the gun supply stores mix it with a slurry of epoxy & paste it where you want it. You. Can even mix micro balloons into the slurry so it has form so you can mold it how you need to without the mix running all over the place.
 

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Mine is hollow, at least I think it is from tapping on it. It doesn't fall on its own, I have a rope tied to the bottom of the board.

What I was going to do was haul it out, drill a inch or so hole in the side at the top and if there isn't any foam in it, I'm going to pour some lead shot in it. Hoping to get at least 30 - 40 lbs. Then pour resin in it to keep it still. Glass the holes back up.

-sent from sea via corked bottle
There is foam in it. Don't drill a hole on the top, the lead has to go in the bottom of the keel. See my previous post.
 

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sunfish?junior?
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Ok I was thinking molten poured lead. My bad. I have poured around 300 Lead joints with running ropes. I had a vision of a wet area and trying to add molten lead to a lead keel filling a void. As you can tell I am not up on what is going on here but I am learning. thanks for info, Lou
 

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formerly 'BoatyardBoy'
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Windway, the hole is near the top, as in when the board is down I'll drill a hole in the side of the board a foot from the shoal keel. And if it does have foam the acetone will take care of that pretty quickly. After that, the lead shot will be poured in the top so it drops to the bottom of the CB and set in place with resin poured over it.

You can't really "paste" the lead shot on the outside because the CB has to go in the trunk and there isn't enough room to put enough shot to make a difference. Not only that but if put the lead on the outside your making the CB wider and bulkier creating more drag.
 

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Windway, the hole is near the top, as in when the board is down I'll drill a hole in the side of the board a foot from the shoal keel. And if it does have foam the acetone will take care of that pretty quickly. After that, the lead shot will be poured in the top so it drops to the bottom of the CB and set in place with resin poured over it.

You can't really "paste" the lead shot on the outside because the CB has to go in the trunk and there isn't enough room to put enough shot to make a difference. Not only that but if put the lead on the outside your making the CB wider and bulkier creating more drag.
Pasting the lead shot needs to go on the bottom only. Did I say sides? My bad if I did. The micro balloons make the epoxy / lead slurry so it will keep it's form so you can actually mold the shape you want ON THE BOTTOM of the board. I would roughen up the bottom (if the sea bead hasn't already), mold the shape I want with the amount of lead shot, then cover it all with glass. You can even shape it with a rasp after it's all cured up prior to glassing if you need to.Just make sure you don't make the keel too long cause it won't fit in the slot...I almost did that. The weight needs to be as far down on the board as you can get it cause that's what keeps the board down when your pinchin the wind.
 

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And if it does have foam the acetone will take care of that pretty quickly. .
My concern on doing this is that the foam provides an inner structure to the fiberglass "skin" of the keel. acetone will "eat" the foam alright but will the lead shot fill all the voids? I think not. Will they make their way to the bottom? Again I think not. Will the lead be evenly distributed, again, no I don't think so. Will the weakened "skin" crack with use over time & allow water in the keel? Maybe, but then again it would make it heavier! LOL Why not just put the lead on the bottom where it belongs & glass it over? My keel pictures are in the mod post, check out the stainless leading edge & bottom plate. This thing is bullet proof.
 

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formerly 'BoatyardBoy'
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My concern on doing this is that the foam provides an inner structure to the fiberglass "skin" of the keel. acetone will "eat" the foam alright but will the lead shot fill all the voids? I think not. Will they make their way to the bottom? Again I think not. Will the lead be evenly distributed, again, no I don't think so. Will the weakened "skin" crack with use over time & allow water in the keel? Maybe, but then again it would make it heavier! LOL Why not just put the lead on the bottom where it belongs & glass it over? My keel pictures are in the mod post, check out the stainless leading edge & bottom plate. This thing is bullet proof.
Foam doesn't provide any structure, it's only there to lay the glad on to provide a shape, had it been wood in there I would say Yea it's probably for structure. I don't see why it wouldn't fill the voids, not only that but the resin poured on top of it will make it one solid piece and fill any voids, nooks, and crannies left. I don't think lead distribution is of that much concern since we're just trying to get the board down. The weight for the ballast is in the shoal keel. As long as the lead shot is in the bottom of the CB then it's successful. Furthermore, I don't think the fiberglass, "skin," would be any weaker, if anything it would be stronger with a solid black of lead and resin at the bottom. It would be no different than sticking it to the bottom.

There's always another way to skin a cat...


-sent from sea via corked bottle
 

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Foam doesn't provide any structure, it's only there to lay the glad on to provide a shape, had it been wood in there I would say Yea it's probably for structure. I don't see why it wouldn't fill the voids, not only that but the resin poured on top of it will make it one solid piece and fill any voids, nooks, and crannies left. I don't think lead distribution is of that much concern since we're just trying to get the board down. The weight for the ballast is in the shoal keel. As long as the lead shot is in the bottom of the CB then it's successful. Furthermore, I don't think the fiberglass, "skin," would be any weaker, if anything it would be stronger with a solid black of lead and resin at the bottom. It would be no different than sticking it to the bottom.

There's always another way to skin a cat...


-sent from sea via corked bottle
For sure, let us know how it works out for ya. I think we can agree to differ...no worries. You can see my keel in the mod section I just put it there if you want.
 

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formerly 'BoatyardBoy'
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For sure, let us know how it works out for ya. I think we can agree to differ...no worries. You can see my keel in the mod section I just put it there if you want.
Oh for sure, I'll check yours out because I'm not grasping your ss rod thing you were talking about. But I'm hoping to get to this either in Jan or March, so I'll post up some pictures and details of it.

-sent from sea via corked bottle
 
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