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· Telstar 28
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Umm... I would add the lead internally. 2800 lbs. of lead ballast only takes up about FOUR CUBIC FEET of space—so, you're looking at two-to-three cubic feet of lead to add, maybe 3.5 cubic feet at the most.

Why not remove the concrete from the encapsulated keel and replace some of it with lead.

You won't be able to laminate a lead shoe to the bottom of your boat with any degree of success IMHO. Lead is a relatively "slippery" material to work with and not much sticks to it with any degree of strength. By putting the ballast inside the boat, you'll eliminate the risk of the new ballast detaching suddenly.
 

· Telstar 28
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MarsMetal isn't really a good option, since the OP isn't replacing a keel bulb, but needs to add to the internal encapsulated keel. Where Mars Metals excels is when you need to have an external keel built to replace an existing keel.

Be aware, if you're melting your own lead, the fumes are toxic, and you'll want a proper respirator.
 

· Telstar 28
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I confuse the two all the time... :) But have little need for either, being a multihull sailor. :)

The one major problem with doing a large casting to put in the bilge of your boat is weight... they're tough to handle in one large piece.

The lead shot encased in resin drops the density, but is relatively easy to handle.

Oops, cross-post with Sailing Dog. I disagree about MArs MEtals -- they do a lot of different lead castings. Mars Keels, on the other hand, specializes in external lead keel foils.
 

· Telstar 28
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Thanks for the quick responses.

The issue with removing some of the original concrete is that there were railroad rails embedded (the previous owner says welded to other framework in the concrete) in the concrete ballast, and they are supporting the engine mounts. I'd like to find an alternative to jackhammering out the concrete under the engine and under the 90 gallon stainless fuel tank.
Damn, that complicates things a bit.

I'm taking a stability class for the new Canadian 150 ton master's ticket and took one a few years ago--but am trying to remember the terms, so please bear with me:

1) wouldn't putting more ballast up higher be less effective than less ballast down lower? The righting arm is the difference between the metacentric height and the centre of gravity, is that sounding about accurate? The longer the righting arm (gm?), the stiffer the boat, the snappier the motion (and also... more uncomfortable at sea!).

So maybe more ballast in the bilge will help me carry a bit more sail, and yet enjoy a slower roll period and more comfy ride. We're just over on our ear... with reefed main and jib in 15 knots (like burying the caprail 1/2 the time--and Cecil Lange told me they should never bury their rail in conditions like that).

2) 4.8 cubic feet of lead doesn't sound like a lot... but how much is that spread over a width of 4 inches and a length of say... 120 inches? Would that make my shoe only 2 inches deep, and spread the weight that is hanging in the fiberglass out effectively? 4 cubic feet--when I think about a cubic yard of way, way, way less dense gravel or even concrete... isn't that almost the size of a dump truck load?
A cubic yard is 27 cubic feet... way more than you need... four cubic feet would be a section 12' long x 2' wide x 2 inches thick...

3) sail choice has a lot to do with it, but still--having to go from a high cut yankee to stays'l and 2ble reefed main in 15 knots and only getting 5 knots for being over... 15 degrees or more... that's unreasonable. That really says "more ballast" to me. When we're offshore and shorthanded and in a larger steeper swell on a murky night with a surprise squall... that degree of tenderness has "knock down" written all over it. The boat doesn't loose control or round up horribly, but it's still asking for trouble.
Yup...need more ballast... :)

4) thanks for the reminder on the fumes. molding lead into steel buckets with a tiger torch? I heard it took hours. Anyone had experience with sand molds? A friend of mine molded some lead in a pig trough. so I guess the steel has a much higher melting point than the lead
Yes, you can make some decent molds for lead out of sand. Lead has a melting point of about 620˚F... Iron has a melting point of about 2800˚F. Silicon Dioxide has a melting point of about 3000˚F.... so you have lots of ways of making the molds for the ingots.

5) thoughts on piercing the hull with bolts, then sealing and glassing over? Just doesn't sound like a good thing if we ever grounded and had to loose the shoe, but could come through otherwise intact... it may not be so clean with bolts tearing holes in the keel
First, the hull may not be able to support the shoe.... since it wasn't designed for the extra weight. The damage the loss of the shoe could cause is really not something I'd want to consider in a hard grounding. Also, adding additional ballast is going to increase your draft as it is... adding it externally penalizes you twice for the additional ballast-once from its weight, and once from its thickness.

6) absolutely a priority to retain keel foil shape... such as it is. Cecil Lange told me his keels were beautiful and did provide some lift, so it's true I don't want to mess with the beauty.

Anyway, appreciate the thoughts. This is a fun, old school project and I hope to keep enough brain cells intact from the melting process to enjoy some safe and fun offshore cruising!
Keep us posted and let us know how it goes.
 
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