Removing ballast

[rfnk]

Early next year I'll commence restoration of our Twister (28' wooden yacht - photos attached). It seems very little has been done to this boat for many years and think (don't really know yet) that I'll need to remove the ballast to check and possibly replace keel bolts as I think the timber around the bolts has been crushed from successive overtightening. My plan is to undo the keel bolts and jack the hull up to release the ballast. i have some rough ideas on how I might do this but I'd be very grateful if anyone has any references to an photos etc. of cradles, props, systems etc. that might provide some ideas. Lifting by crane is not an economical option as access is limited. Rick

[PAR]

You can jack her up, but this is very hard on the structure, often resulting in tension breaks in the frames, pulled floor fastenings, distorted/sprung planking and stringers, etc.

You should evaluate the structure first. This is a daunting task for the novice, as there are so many issues that have to be looked at. The best and usual course is to have the boat looked over by a carpenter or get it surveyed by a person familiar with the type.

Just in the one photo of her on the hard, I can see several potential issues that could spell serious pain if not addressed properly. On those old CCA style yachts (depending on designer and builder) the ballast casting many times played a fair role in the support of the structure, so it's removal has to be carefully considered and arranged, so she doesn't loose shape.

Since she's got lovely overhangs, you have "purchase" room for slings, dropped from an overhead. The boat shouldn't weight much, maybe a few tons, which isn't much weight in the big picture of things. A couple of chain falls, mounted on home made U shaped supports, straddling the boat, fore and aft will get it done safely. Think doubled up 2x6's for the legs and doubled 2x8's or bigger for the cross pieces. Tie the slings together so they don't slip on the forefoot. I'd remove the engine and trans first (Atomic 4?), as well as much of the other "heavy" stuff aboard. Some one with a front end loader or back hoe could make quick and safe work of it too and it's my preferred method, now that I'm older and not willing to die under a boat, during a bad lift attempt any more.

Do yourself a favor and invest in some real jack stands, you'll need 5, four regular sailboat stands (the angled ones), two on each side and a bow support type. Conversely, you can make a cradle. It wouldn't hurt having a bow type stand under that counter too. As currently propped up, the sheer is being distorted by the 4x4's along the rail. She's supported, but not well and will begin to distort in short order in this condition, especially when the ground under the keel settles more then those sheer props.

[rfnk]

Thanks PAR, that's helpful. By jacking it up I did mean by way of a cradle or slings - your suggested specs are very helpful. The props you see are only temporary following placement in our yard. I'll be putting together proper props etc. before commencing work. Thanks for the tip re using a front end loader too. The engine is already out - it was a Bukh, apparently, but I'm not sure what capacity. I'll also be removing much of the interior fittings and anything removable prior to lifting. I'm not sure what you mean by CCA (Cruising Club America?) type yacht - the Twister was designed in the 1960s by Kim Holman, an English designer who also designed the Stella. Our boat was built in Sydney by a Dane called Johannsen, who I believe, was brought to Australia to work on Dame Pattie (the America's Cup challenger - not the prime minister's wife! (the boat was named after her though)) and built quite a few boats during his time in Australia. Johannsen also built our Folkboat, which we recently restored (picture attached). Thanks again, Rick

[rfnk]

PAR
Just a bit of extra information. The Twister weighs 4 tons; I assume the ballast would be around half that. The keel is currently sitting on timbers laid across a brick and concrete path whereas the other props are on relatively softer ground. I checked this in response to your warning about distorting the sheer - thanks! Rick

[rfnk]

And I've just read this excellent article by Ted Brewer so now have some idea on the relevance of CCA to the Twister! Rick

http://www.boatus.com/goodoldboat/ratingrules.asp

[PAR]

Your boat very likely carries 3,000 or more probably 2,500 pounds of ballast. CCA yachts of that general type are great sea boats, comfortable and easily managed. They don't have the fat butted accommodations of modern craft of the same LOD, but they ride a lot better in a rough slosh. Most of them were well rounded vessels, some especially toward the end of the CCA era, sported weird stuff like bustles and appendages shaped like shark fins or platypus beaks. I've always enjoyed the CCA yachts (I've owned several), even if their interiors are a bit tight by today's standards.

[rfnk]

Thanks PAR. The interior of Windrose is certainly roomier than our Folkboat but we're not planning too many cocktail parties nevertheless. Here's a picture of the ballast. Unfortunately I took this before we blasted the growth off but you can just make out the outline. As you thought might be the case, not quite a straight slab bolted onto the bottom. Don't worry though, I have a good shipwright friend who'll be helping with the ballast removal exercise (if it indeed proves necessary). Rick