Carvel Planking Ep24 Lofting the Ballast Keel

The lead ballast keel has been delivered from the foundry for Sydney Wooden Boat School Principal Ian Smith's 24' Ranger class gaff sloop. Ian explains how he lofted the plans for the keel in order to build the plug, and the process of actually building the plug to the shape that the foundry will cast in lead. This is episode 24 in Ian's series on Carvel Planking on @SmithysBoatshed Channel.

[@EmmettOconnor-sg7uv]

Cheers mate! Bloody legend!

[@clydecessna737]

Lofting = Dark Art.

[@wandeenboatbuilding3524]

Great video, as usual Ian. It looks like some serious boring to be done. L Fancis Herreshoff had some interesting ideas on keel bolts.

[@billstevens3796]

Two ballast keels? What's the other one for? Did I miss something? Great stuff as always!

[@SteelDoesMyWill]

The silver painted one on the right in last shot of the video is the wooden plug mold that Ian made. The foundry uses sand molding, they put the wooden plug into a specific type of sand that compacts well and holds its shape. Sometimes that sand is a large story box or even directly in the ground. The sand is compacted around the plug as it is poured in so it's very stiff, then the plug is removed by pulling it straight up and out which leaves a void to the exact shape of the plug. They can pour the molten lead directly into the sand mold and let it sit overnight to cool. Keep in mind that lead melts at a much lower temperature than bronze or steel, it also shrinks a lot. The plug mold usually has to be made about 3% larger than the dimension you would want the final keel to be to allow for shrinkage. BTW, its pretty handy to keep the wooden plug mold to sell to anyone who wants to build another copy of this boat.