Discussions on everything about the J/30 Sailboat!
With your one stop source
The J/30 Marketplace
Join or Renew
Class Membership
Search

March
M T W T F S S
1 2 3
4 5 6 7 8 9 10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30 31
Today's Birthdays
No Birthdays
Newest Members
zharv, Corey, Suzie, SSA-BlueJ, Liam Kersch
1017 Registered Users
Crew Manager Boat Websites

Boat Website subscriptions with
Crew Scheduling & Notifications

Created by former J/30 Rhapsody owner

J/30 Social Network
Popular Topics(Views)
976,298 Dacron Main
162,662 Ananda's Refit
Forum Statistics
Forums28
Topics3,983
Posts19,061
Members1,018
Most Online238
Feb 9th, 2024
Previous Thread
Next Thread
Print Thread
Weight and waterline #18180
03/21/19 08:30 AM
03/21/19 08:30 AM
Joined: Jul 2018
Posts: 76
Burton, Michigan
N
nathankt79 Offline OP
Senior Member
nathankt79  Offline OP
Senior Member
N
Joined: Jul 2018
Posts: 76
Burton, Michigan
Does anyone have a handle on how much weight (on or off) will move the waterline on a J/30 a given distance...For instance, something like 300lbs=1"?

Thanks,

Nate

West Marine Affiliate Program

The J/30 Class Association has partnered with West Marine and is now a member of the West Marine affiliate program. You can support the J/30 Class when you make your West Marine purchases online. The J/30 Class Association receives a percentage of sales from your purchases when you click through from our website. Click the logo above and you will be directed to the West Marine website with a cookie that identifies you as a J/30 affiliate. You can also use any discounts that you may be authorized.
Re: Weight and waterline [Re: nathankt79] #18183
03/23/19 06:17 PM
03/23/19 06:17 PM
Joined: Sep 2000
Posts: 393
Rockwood, MI, USA
Russ Atkinson Offline
Senior Member
Russ Atkinson  Offline
Senior Member
Joined: Sep 2000
Posts: 393
Rockwood, MI, USA
How good is your math? I don't think there is a simple straight line ratio for pounds to inches since the hull gets wider and longer as it sits deeper in the water. That said lets do some simple math. 1 cubic foot of water weighs 62.43 pound. At the water line the boat is about 25' long and 8 ft wide. Figure the area of an eclipse that is 25' X 8' wide. Multiply it by 1/12' (1"). You will then have a rough idea of cubic feet of 1" of water at the water line
If your boat is out of the water - measure how much longer and wider it is 1" higher than the water line, 2" higher than the water line,etc.
Multiply each of those calc by the wight of 1cubic ft of water. It won't be exact but it will get you in the ball park.

Re: Weight and waterline [Re: nathankt79] #18188
03/25/19 11:16 AM
03/25/19 11:16 AM
Joined: Jul 2018
Posts: 76
Burton, Michigan
N
nathankt79 Offline OP
Senior Member
nathankt79  Offline OP
Senior Member
N
Joined: Jul 2018
Posts: 76
Burton, Michigan
Thanks for the input. I can probably riddle that out. I was really hoping someone already figured out a chart or something, lol. I'm trying to figure out how much the weight savings of switching to lithium batteries would have on freeboard. I also read something that said if one can reduce weight forward and aft of the center 1/3 of the hull, she'll cut through waves a bit better without "slapping".

Re: Weight and waterline [Re: nathankt79] #18286
07/22/19 12:36 PM
07/22/19 12:36 PM
Joined: Jul 2019
Posts: 1
Melbourne, FL
J
Johnny Blizzard Offline
Forum Newbie
Johnny Blizzard  Offline
Forum Newbie
J
Joined: Jul 2019
Posts: 1
Melbourne, FL
nathankt79, Did you get your weight-to-freeboard question figured out?

Re: Weight and waterline [Re: nathankt79] #18296
08/17/19 02:27 PM
08/17/19 02:27 PM
Joined: Jul 2018
Posts: 76
Burton, Michigan
N
nathankt79 Offline OP
Senior Member
nathankt79  Offline OP
Senior Member
N
Joined: Jul 2018
Posts: 76
Burton, Michigan
No...I kinda gave up on that one.


Moderated by  David Erwin 

Who's Online Now
0 registered members (), 34 guests, and 1 spider.
Key: Admin, Global Mod, Mod
Photos
2023 Clipper Cup - Conundrum USA32866
Windy Wednesday night
Hurricane Gulch San Pedro, CA
Truckin'
Endeavour (246) Sailing in Prince Edward Island
Recent Posts
Hull # 229 Falcon parts for sale
by Sunrise. 03/16/24 08:26 PM
Adjusting Throttle & Transmission Controls
by Rhapsody #348. 03/10/24 08:25 AM
Engine Cover Steps
by David Erwin. 03/10/24 01:35 AM
Cushions
by Corey. 02/25/24 10:02 PM
Sold: #2 Dacron Jib
by Brent. 02/17/24 05:12 PM
J/30 Survey
by David Erwin. 02/16/24 06:43 PM
looking for j30 center table
by wilybilds. 02/16/24 04:49 PM
1984 J/30 - Hull #488 Shamrock
by Bruce Irvin. 01/30/24 12:12 AM
Cabin Table Wanted
by B Davis. 01/20/24 11:03 PM
Fuel Fill O Ring
by watchoverya. 01/11/24 05:35 PM
Powered by UBB.threads™ PHP Forum Software 7.6.1.1