Draft question

Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
Google sail calculator. O'day 34/35 are listed as 1156lb/inch. Or 1 inch more draft for each 1156 lbs over your design weight.
The number is only accurate for the first inch. It changes for each additional inch.

Google isn't necessary - the link is in the post before yours.
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
There's only so much you can put to discussing draft without being in the bar, or the bathtub up here in February. It's still -20 in the morning.

Sigh.
 
Oct 29, 2005
2,366
Hunter Marine 326 303 Singapore
What about calibrating depth from keel bottom? Won't that be safer?
 
Feb 26, 2004
23,347
Catalina 34 224 Maple Bay, BC, Canada
What about calibrating depth from keel bottom? Won't that be safer?
Safer than what?

This, as you can imagine, is a recurring question.

Some skippers like waterline, some like bottom of keel.

I just gently nudged my boat onto a soft mud bank, deliberately, once. The depthsounder read 4.4. That's all I need to know, no math required. It simply answered the question: What does my deptsounder read when we touch?

Your boat, your choice. :):):)
 
Sep 15, 2009
6,244
S2 9.2a Fairhope Al
Safer than what?

This, as you can imagine, is a recurring question.

Some skippers like waterline, some like bottom of keel.

I just gently nudged my boat onto a soft mud bank, deliberately, once. The depthsounder read 4.4. That's all I need to know, no math required. It simply answered the question: What does my deptsounder read when we touch?

Your boat, your choice. :):):)
lol i had a power boat one time with the depth alarm set at 3 ft ...was running a channel out of beaufort sc on way to broad river .....well we run aground and at that very moment of impact the alarm went off and my buddy and i both in our suprise looked at the depth sounder as if to say what took you so long so no matter what you set it at you better have a mental note of where you are at all times ...yes stu you are right ...safer than what ....lol
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
From Stu's commentary today, people will be waving at him on their way south, but failing to realize he's stuck in the mud. :)
 
Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
There's only so much you can put to discussing draft without being in the bar, or the bathtub up here in February. It's still -20 in the morning.

Sigh.
That's what you get for living in a frozen wasteland rather than a Canadian paradise.

Move to the coast. The sailing is better too.:)

Currently 10 degrees Celsius at 9 pm in Victoria Harbour - 50 F for our US friends.
 
Oct 29, 2005
2,366
Hunter Marine 326 303 Singapore
Stu is never stuck in mud. He's just taking keel sounding and while he's at it, no harm clearing couple barnacles from hard to reach place. ;)
 
Dec 14, 2003
1,450
Hunter 34 Lake of Two Mountains, QC, Can
How many recreational powerboaters would know what the dayshape meant even if it were displayed and if they even noticed it? I doubt many.

How many even know that the to them mid-mast light means the sailboat is running under power ?
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
That's what you get for living in a frozen wasteland rather than a Canadian paradise. Move to the coast. The sailing is better too.:) Currently 10 degrees Celsius at 9 pm in Victoria Harbour - 50 F for our US friends.
Sigh. Don't remind me. :)
 
May 23, 2004
3,319
I'm in the market as were . Colonial Beach
In thinking about this post I will give you two thoughts of mine.

No matter what your draft is, you WILL run aground. It happens to everyone.

If it is a close call on the charts and the tide is not high, AVOID it!

When you have to go skinny, go slow. It is better to bump bottom then to slam into it.

Always round your depth up. My Catalina 30 had 3'10" of draft. I always said I had a 4 foot draft. My current boat, Compac 23, has 2'3" of draft. I say I am 2.5' for draft.
 

RMelis

.
Oct 23, 2014
3
Hunter 35.5 Pensacola
Beer draft

Just a newbee question. I have an O'Day 34 listed as having a 4'3" draft. I assume this is dry weight, not having my 50 gallons of fresh water tanks filled and fuel tank filled or any gear aboard. Am I correct ?Does it take a lot of weight to change this ? There are just the 2 of us aboard and there is so much skinny water with many turns and power boat owners which always feel they have the right of way. How much weight approximately does it change to affect my draft. I always keep at least 5 + ft. of water below by transducer which is at the lowest point of my hull possible. I have my boat at the Cape Coral Yacht Club and although its a great marina, its about 10 miles of ICW travel to areas of deeper water. Thank you for your help
Frank
My wife and I bought our Hunter 35.5 ten years ago and were delighted that its' draft was listed as 4.5 feet because the West coast of Florida has a lot of skinny water. Then, in preparation for a lengthy cruise, we put 200 more feet of chain aboard, two more anchors, filled the sixty gallon water tank, filled the 22 gallon fuel tank and four 5 gal. fuel containers, brought lots of food, clothes cleaning supplies and tools, loaded cases of bottled water, soda and beer - and in the back of a shallow harbor, we stopped moving forward when the depth finder read five feet. We have since reduced our loading but raised our bottom paint level.
 

LloydB

.
Jan 15, 2006
927
Macgregor 22 Silverton
Another approach could be to plug the scuppers and dump 100 gallons of water into the cockpit. Grab a fishing pole and hang a bobber just off the water surface from off the stern. By looking at the boat from the dock before and after, you should have a fair idea of what the waterline will look like with 3 times that weight in it after you pull the plug. (or six times for that matter @8 lb/gal)
 

Bob J.

.
Apr 14, 2009
775
Sabre 28 NH

Restricted
Maneuverability
:D
I like this, it's much more nautical than saying "we're experiencing air turbulence".
That's a real straightforward answer & excellent advice Stu. Now if we could only patent this:D
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
, you WILL run aground. It happens to everyone.
Nah, nobody is ever going to admit to that kind of activity. Nope. No sir. Never happened.
Didn't see it, don't know anything about it, wasn't there, can't blame me for any of it.
:naughty:
 

Sailm8

.
Feb 21, 2008
1,751
Hunter 29.5 Punta Gorda
Nah, nobody is ever going to admit to that kind of activity. Nope. No sir. Never happened.
Didn't see it, don't know anything about it, wasn't there, can't blame me for any of it.
:naughty:
True dat! The tow boat was just along side to borrow some Grey Poupon.
 
Jul 22, 2011
146
Mariner Yacht Co.(NH) Mariner 28 Atlantic Highlands, NJ
This will proablely not be terribly helpful, but boats are designed to float on their lwl, loaded water line, so draft should be calculated from there. What load is used to determine lwl? Well it depends. I would suggest trying to find a owner's manual, many O'Day manuals are on line, which may give that information.You could unload the boat, measure draft, and load the boat measure draft and figure the difference, subtracting tide movement during the time it takes to load and unload the boat. Sometimes designers use a light load so waterline is shorter for racing ratings, but I don't think O'Day is in that mode. I am hoping the information for LWL is at least somewhat helpful
Lou