Waterline paint question: How to factor in provisioning weight?

[chrisncate]

Should I move the waterline up when I paint her this year in preparation for an extended cruise? It seems like I'd have to. She's going to be heavy. How do I figure out how high I need to go with it?

[sailingdog]

What's the PPI for your boat??? What boat do you have?

The PPI tells you how much weight it takes to lower the boat in the water—pounds per inch... and if you have a rough idea of how much gear you'll be putting aboard, you'll have an idea of how many inches to raise the water line.

BTW, one figure I've heard of for cruising full time is to add 1500 lbs per person. IIRC, that is supposed to account for the person, their clothing and gear, and their food and water... but I don't know how accurate this is.

[RichH]

PPI or Pounds per Inch is what you should be looking for

PPI = pounds LOAD that will more deeply immerse the water line by 1 inch

Go to: Sail Calculator Pro v3.53 - 2000+ boats & find your boat in the left hand column of part #1 and 'click'; then go to Part #2 and find the parameters of your boat, including PPI

[RichH]

Originally Posted by sailingdog

BTW, one figure I've heard of for cruising full time is to add 1500 lbs per person. IIRC, that is supposed to account for the person, their clothing and gear, and their food and water... but I don't know how accurate this is.

Thats pretty close to actual for a long term cruising load - IMO

[sailingdog]

Originally Posted by RichH

Thats pretty close to actual for a long term cruising load - IMO

Given who I got the info from, I thought it was pretty close to right, but wasn't sure.

Obviously, for a shorter cruise, the load will be less, though more than what you'd have daysailing. I'd say any cruise four-weeks or longer in duration is going to probably be at the 1500 lbs. per person point as a rough guess, unless you're stopping in marinas every night...

[chrisncate]

Excellent info, thanks! I searched it, but couldn't find it here.

Edit: looking now...

[chrisncate]

678 ppi

[chrisncate]

Ok, the waterline need to be at the first spreader.

All you will see is my mast apparently.. like a U boat...

[sailingdog]

Originally Posted by chrisncate

678 ppi

Just remember, the PPI generally increases as the boat gets lower in the water since the waterplane area generally increases, at least to a point... then the boat sinks... So, if you're going on a summer cruise with two people, you'd probably want to raise the waterline FOUR inches or so on your boat.

[chrisncate]

Originally Posted by sailingdog

Just remember, the PPI generally increases as the boat gets lower in the water since the waterplane area generally increases, at least to a point... then the boat sinks... So, if you're going on a summer cruise with two people, you'd probably want to raise the waterline FOUR inches or so on your boat.

I plan on some heavy gear though, 250' of chain, multiple rodes, min of 3 anchors, etc etc... Im going to add it all up tonight to see if I can estimate the weight.