Bow Heavy

[Nomad Willy]

Soo Valley wrote;
“Eric, I must respectfully disagree. Since this is very common with GB for decades, if the designers thought you were correct they would have made modifications.
Previously I had planning hulls and they had the CG aft of center, so again the engineers must have worked the design for optimum layout.”

A boat with a CG the way the designer called it may be an unusual boat. Things like #of engines and their location may be the call of the marketing dept.

Re how constant the designers were are the single and twin engine locations the same fore and aft? But perhaps they moved other weighty things to compensate. But one would think if the twin was right one would need to have the single w engine right where the head is on the drawing in post# 23.
But I’ve never heard of a GB skipper complain about the seaworthyness or handling of a GB boat. Some say the’re “wet” tho.

And of course you’ve heard the expression “she floats on her lines”. Never “she runs on her lines at cruising speeds”.

 

[Nomad Willy]

Mark I don’t think I’ve ever seen your Coot at an attitude. She’s always level w the horizon.

 

[rslifkin]

Got 3/8-inch chain (200 feet), but I'm still bow-light with full tanks. (Engine midship, fuel slightly behind, and water tanks toward the stern.) But never extremely out of balance.

Your boat is pretty full up forward compared to most on here if I remember correctly. So it's probably harder to get it out of trim with weight up forward.

 

[psneeld]

If the Albin 36 is anything like the 40, most of the discussion is off base I think.... especially comparisons to other vessels.

There is hardly any buoyancy forward of the windshield and the anchor locker is tiny and all the way forward underneath the pulpit. So yes, a heavy anchor and chain make a huge difference on my 40....and my guess the 36 as well.

Filling the aft water tanks (180 gallons or so....hard to believe the 36 is 300 gal) raises the bow a few inches where 200 pounds forward may sink it 4 to 6 by the bow.

Most Albins I have seen cruising appear a bit bow down till they try and climb their bow wave. Maybe that's what the designer expected and wanted....a boat that rode level versus squatting.

 

[Nomad Willy]

The only boats that run squatting at less than hull speed (like Mark says .. a knot below hull speed) are seriously heavy aft. Heavy aft is another conversation.
But smaller boats should run the better part of a knot below hull speed “on their lines”. Marine architects don’t IMO design boats to run on their lines at speeds whereas the bow has risen some (about hull speed or a little less (like half a knot). This of course varies some re WL hull length. Think two knots w a 65’ boat.

I’ve always assumed the line quite parallel to the WL at rest is the line referred to in the expression “floating on her lines”. This “line” takes form like a small U shaped depression on the hull like wood boat seams. My Willard had such a line and also “lines” that looked like plank seams on a wood boat and you’d be amazed how many people are fooled.
But I’ve never had it confirmed that the horizontal line was related to the expression “floating on her lines”. It’s been an assumption of mine. Floating on her lines may have all to do w the hull form lines and nothing to do w trim and ballast. But I think the horizontal line just above the water is for trim and possible ballast.

Anybody enough of a NA to know for sure?

 

[Nomad Willy]

Your boat is pretty full up forward compared to most on here if I remember correctly. So it's probably harder to get it out of trim with weight up forward.

I fully agree.

 

[Art]

Actual hull trim positions... as well as visual appearances, at standstill and during speeds, regarding boot stripe and bottom paint lines.

Boot stripe paint-on was begun back in the 50's as an added piece of "visual jewelry"... to enhance the appearance of a "pleasure" boat. Boat sales persons loved the boot stripe embellishment [gotta admit I like em too]. Previously, "boot stripes" were non existent... bottom paint line signified the trim of a boat in a standstill, at rest position - only. Bottom paint is for one reason - only! To help keep the bottom clear from growths while boat is at rest. Boot stripe line, similar to bottom paint line only signifies trim position of a boat at standstill. And, in reality... boot stripe is meaningless, except for visual beautification. Both the bottom paint and boot stripe lines have no correlation as to how a boat should or would trim-out while underway at any speed.

Point in fact:

We just yesterday launched our Tolly after a full on bottom refurbishment project. Included was a newly painted boot stripe [in the original "Tolly Teal" factory color]. By the photos you will see that our boat's bottom and boot stripe paint lines work well in a standstill trim position. I believe these are the original lines established at the factory in 1977. Weights on boat: 75% fuel, 95% water... many tools, some spare parts, furniture, food, cloths... etc.

In other words... with a nearly full weight-load aboard [sans people] the boot stripe and bottom paint lines are near perfect for boat trim.

Of course, when we cruised at 6.3 knots [7.25 mph - just under hull speed of 7.58] traveling back to our covered berth (see last two photos - first photo is haul out pre bottom job]... I'm confident that the lines of boot stripe as well as bottom paint were no where near as correct looking as when at standstill - and - I could care less! Because: I know from the very minor turbulence and wake at stern, as well as the slim bow wave... that our Tolly cruises well in her designed for "trim" position at that relaxing and economical relatively slow cruise speed... twin gassers each turning in sync at 2K +/- rpm.

 

[Nomad Willy]

Good post Art,
Re what you said about probable trim line history I suspect they put a carved groove line on wood boats 30’s, 40’s and 50’s that was dictated by NA’s on drawings and put on boats.

There’s got to be a story … and somebody knows.

 

[koliver]

Good post Art,
Re what you said about probable trim line history I suspect they put a carved groove line on wood boats 30’s, 40’s and 50’s that was dictated by NA’s on drawings and put on boats.

There’s got to be a story … and somebody knows.

Imitating the carved groove line on the hull of my plastic boat was good the day I bought the boat, after it had been unloaded from the PO and before I loaded anything on. In the first year, I raised the boot stripe 4". When the kids stopped coming along I lowered it to its present level, still about 3" above the grooved line.
That is a still position. At 8 knots, the wave curls about a foot up at the bow, and down 6" by amidships. If the line was supposed to follow a moving position, it would only be at the right level at one very specific speed. Brings to mind a stopped clock, correct once every 12 hours.

 

[markpierce]

Mark I don’t think I’ve ever seen your Coot at an attitude. She’s always level w the horizon.

You should have seen her list to port when the dinghy filled with rain water.

 

[Andy G]

Brings to mind a stopped clock, correct once every 12 hours.

Sorry for the hijack, shouldn't that be twice?

Hmm, my partner doesn't agree with me. (this is the type of stuff you do in lockdown)