Casting a lead ballast keel

[Will Brooks]

Greetings, Am working out how to cast 100kg of lead for a Robert Tucker Silhouette. Plan calls for an iron ballast keel but I have found some 10kg Lead ingots. Intend using a wood mold. Have lead industry experience so no comments re health effects please. Would anyone who has done this at home or in a workshop please comment.
Have just finished fairing the framework and will answer questions about the boat if anyone is interested.
You can email me at Maryandwillbrooks@bigpond.com or Brooksw@pasminco.com.au
Regards, Will

[gonzo]

Coat the wooden mold with lime (whitewash) to prevent it from burning. Add some antimonium to the lead, 1 to 2%, to make it easier to machine and a bit harder.

[ErikG]

What does lime (whitewash ) mean?
The only lime i know of is a bittersweet greenish fruit, and I guess that's not really it

ErikG

[SailDesign]

Will,
Do NOT forget that lead shrinks as it cools. If you build a mould to the finished shape, you will end up with a keel about 10% underweight.
Steve

I believe lime is calcium oxide but don't quote me on that.

[gonzo]

If you can't get lime, what it's used for whitewash, plaster of paris would work too.

[Art Read]

Go to a ceramics supply house and ask for refractory cement. (They use it in kilns....) Worked for my 750 lb. keel.

[Polarity]

How to do this step by step from someone doing just that:

http://www.rutuonline.com/html/the_keel.html

Even if you are not its a great and entertaining site, this guy is really a tallented home builder!

Paul

[SailDesign]

Paul,
Glenn Ashmore is a great guy, and an "amateur" in the true sense of the word. (Amateur = one who loves something)
I know him from the rec.boats.building group, where he is a active and friendly soul, full of good advice most of which comes from bitter experience. ;-)
Steve

[Polarity]

He certainly does!
After I posted the above I went through his entire site again. I'm pretty handy given the right tools (and a book !) but anyone who would even contemplate, let alone suceed in making their own composite steering gear, pedestal and Carbon fiber wheel has my utmost respect and admiration!

His site has not been updated for a while - do you know if his project slowed or has he just been too busy to update the site?

Paul

[SailDesign]

Paul,
As far as I can gather he is nearing the end. His current bugaboo is building tanks. Should be weld plastic water tanks to fit the spaces he has, or build welded alu tanks, or what? Wiring and plumbing issues have been discussed recently as well, so I think the "Building" phase has moved from major (pretty) parts to the hidden but vital pieces.
STeve