Keel Ballast

My friend and me are doing bare hull restorations on Two Choey Lee Offshore 27's. We have even pulled the iron out of the keels so we can replace it with lead to lower the CG and make room for batteries. But we do not know how much of the original weight to put back in the way of lead, batteries, fuel and water tankage. The iron filled up the entire keel; but lead is almost half of the volume for the same weight and then we plan to put batteries and fuel on top of that. And we are putting water tanks just above the keel. Is there anything important we need to know? Can we reduce the total ballast if the CG is lower? Can we add more power to the rig? These little 27's will turn out to be amazing little classics with a high tech flair and they will definitely be going offshore, way offshore. Time is of the essence, my friend has already poured his lead; and yes, he is in the foundry business.

Thanks,

Brett

 

Lead is not twice the density of iron. Lead is 11340kg/Cu.m and iron is 7870kg/Cu.m. Hence lead is 44% more dense.

I would add the same weight of lead as the iron you replace to get the boat at the same waterline and enjoy the benefit of the extra sail carrying capacity. Doubt that the benefit would warrant a change in rig just the ability to hold full sail longer.

Rick W.

 

Thanks Rick, not messing with the waterline seems to make perfect sense

 

Placing batteries in a vulnerable location where they might come into semi submerging ocean water might be dangerous, though not fatal. I once had an old Alden with 3' of water intrusion and could sense the DC current in the water. Also, it can destroy sensistive items linked to the battery system.

Ray

 

Thanks for the heads up Ray. It is such a small boat, the rewards are worth the risk; especially since I am building the boat to be simple and bullet proof.