May 30, 2015, 10:17 PM
Registered User
United States, MN, Brainerd
Joined Oct 2004
2,492 Posts
Quote:
 Originally Posted by RevWarBrig Any estimates on the final ballast total needed? Looking well over 100 lbs. to me.
Hey Jeff,
Rather than that much lead, what if you laid in a capped length of PVC pipe in the bottom of the hull, with ports to the open water. Set up to flood like the ballast tanks on a submarine. Not as dense as lead, and a lot of lead would still be used, but at least some significant amount of weight would be taken on when the hull is put in water, and that same amount drained out as she is removed from the water.
Perhaps valves could be used to flood the "ballast tank" to trim her to proper water line, then closed.
 May 30, 2015, 11:41 PM SCALE Sailor United States, MD, Severna Park Joined Apr 2008 1,828 Posts I'll wager the kid won't fit anymore Last edited by JerryTodd; Yesterday at 12:51 AM.
May 31, 2015, 10:13 AM
Registered User
United States, MN, Brainerd
Joined Oct 2004
2,492 Posts
Quote:
 Originally Posted by JerryTodd I'm guessing Fair American with a LWL of about 64" beam of 24" and depth of about 12" would displace about 295 pounds of fresh water.
It may be more like this:

Hull "block" volume estimate: 64 x 24 x 12 = 18,432 cubic inches

Corrected hull volume estimate; 18,432 cu in x 0.55 = 10,138 cu in
(the 0.55 factor is from actual measurements and weights of Syren, representing
a ca. 1800 brig hull shape)

Hull Volume x Water Density: 10,138 cu in x 0.036 lbs/cu in = 365 lbs

Total model weight with needed additional ballast = 365 lbs

Estimated extra ballast needed will be 365 lbs minus the finished model weight.
Last edited by DanL; May 31, 2015 at 10:32 AM.
 May 31, 2015, 01:15 PM SCALE Sailor United States, MD, Severna Park Joined Apr 2008 1,828 Posts Guess I didn't remember correctly