Reply
 
Thread Tools Display Modes
 
Old 02-07-2013, 06:09 PM   #41
Guru
 
Insequent's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 1,426
Quote:
Originally Posted by markpierce View Post
Will you be able to take advantage of favorable currents?
Definitely, and likely wind as well. The plan is to travel when and where I get the benefits but to assume zero benefit for trip planning in order to have a bit extra margin.
__________________
Advertisement

__________________
Brian
Insequent is offline   Reply With Quote
Old 02-07-2013, 06:32 PM   #42
Guru
 
Insequent's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 1,426
Quote:
Originally Posted by Tad Roberts View Post
Most average "trawler yachts" will run out of positive stability at between 70 and 80 degrees heel. A few years back I did studies of a DD44 and Nordhavn 55 and that was the conclusion.

The good news is that heeling more than about 50 degrees is very rare in modern motor yacht cruising. The exception being in bar crossing situations. When was the last time you heard of a motor yacht being capsized by a wave? Downflooding is the greater danger, via broken windows or open vents.
Tad
I'll likely try and find you in a few months, to engage you to do an inclining test for me. And to look hard at my plans for window protection, which is not getting done at present.

But one thing I will grapple with right now is the inlet and outlet engine room ventilation openings. They are 24.5" x 6.5", four in total and about 3' above waterline and 1' below the shear. I'm contemplating a flap or 'check valve' on the outflow vents at the rear. For intakes, I'm thinking of a manually operated closure that is set if weather is poor, and then locking the engine room access door open for air intake from the master stateroom. A bit noisy, perhaps a bit of unwanted heat but it should not be needed very often. I would still be vulnerable to a rogue wave knockdown. But I cant conceive an automatic shutter for the intake vent.
__________________

__________________
Brian
Insequent is offline   Reply With Quote
Old 02-07-2013, 06:57 PM   #43
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Country: USA
Vessel Name: Carquinez Coot
Vessel Model: 2011 Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 10,265
Quote:
Originally Posted by Insequent View Post
... then if its still a reasonable time of the year to head to San Fran ..
Open your Golden Gate!

__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 02-07-2013, 07:13 PM   #44
Guru
 
Tad Roberts's Avatar
 
City: Flattop Islands
Country: Canada
Vessel Name: Blackfish
Vessel Model: custom
Join Date: Dec 2012
Posts: 707
Quote:
Originally Posted by Insequent View Post
Tad
I'll likely try and find you in a few months, to engage you to do an inclining test for me. And to look hard at my plans for window protection, which is not getting done at present.

But one thing I will grapple with right now is the inlet and outlet engine room ventilation openings. They are 24.5" x 6.5", four in total and about 3' above waterline and 1' below the shear. I'm contemplating a flap or 'check valve' on the outflow vents at the rear. For intakes, I'm thinking of a manually operated closure that is set if weather is poor, and then locking the engine room access door open for air intake from the master stateroom. A bit noisy, perhaps a bit of unwanted heat but it should not be needed very often. I would still be vulnerable to a rogue wave knockdown. But I cant conceive an automatic shutter for the intake vent.
Brian,

Don't think I'm turning down work cause I'm not, but I can pretty much talk you through doing your own inclining. As this is (I'm assuming) for your information rather than any regulatory agency, there's no real reason for me to witness it. It's a simple mechanical procedure that provides part of the information to establish real stability figures.

To create a stability curve showing righting arm lengths at various heel angles we also need flotation measurements and the hull lines.

Storm windows can be various materials, light aluminum plate works nicely, plywood (cheap) and plexiglass (expensive) are often used, some of the new sheet plastics would work as well. One method of fastening is to epoxy nuts in place (either flush or proud) and just thread bolts through your cover and into the nut. Other folks have used posts or brackets around the edge with a latch of some sort(a bit ugly).

Are the engine vents in the house or the bulwark? Any chance of building outside extensions on them to raise the downflooding angle? You could fit bolt on covers for them just like the storm windows.
Tad Roberts is offline   Reply With Quote
Old 02-07-2013, 07:27 PM   #45
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Country: USA
Vessel Name: Carquinez Coot
Vessel Model: 2011 Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 10,265
The over-built Coot has provision for storm windows, but screwing them down probably would strip paint in the screw holes, requiring touch-up paint to prevent corrosion.



I ought to query the builder to find out the proper screw/bolt size.
__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 02-07-2013, 08:20 PM   #46
Guru
 
Insequent's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 1,426
Quote:
Originally Posted by Tad Roberts View Post
Brian,

Don't think I'm turning down work cause I'm not, but I can pretty much talk you through doing your own inclining. As this is (I'm assuming) for your information rather than any regulatory agency, there's no real reason for me to witness it. It's a simple mechanical procedure that provides part of the information to establish real stability figures.

To create a stability curve showing righting arm lengths at various heel angles we also need flotation measurements and the hull lines.

Storm windows can be various materials, light aluminum plate works nicely, plywood (cheap) and plexiglass (expensive) are often used, some of the new sheet plastics would work as well. One method of fastening is to epoxy nuts in place (either flush or proud) and just thread bolts through your cover and into the nut. Other folks have used posts or brackets around the edge with a latch of some sort(a bit ugly).

Are the engine vents in the house or the bulwark? Any chance of building outside extensions on them to raise the downflooding angle? You could fit bolt on covers for them just like the storm windows.
Tad - if you are too busy that's fine. Lets see in a couple of months.
On my 'to do' list is to measure the hull lines .... Doesn't seem too difficult, just a bit painstaking so I'm procrastinating.

I think for the big saloon windows some aly plate with a stiffener or two would be good. Nuts epoxied in place would be fine, and they could have a short bolt in them to keep thread clean when not in use. They might also be able to be used for fixing sun shades in place.

For the pilothouse windows I had in mind a two part solution. First replacing with thicker laminated glass and second being able to fit a removable bracket that has a 4-6" pressure pad in the center of the window that can be tensioned up to a suitable level. It would absorb deflection of the glass when hit by a wave.

My engine vents are in the bulwark, not easy to extend in an elegant way at least. See pic. I could seal those and have the openings on the inside, along the deck walkway, or even on the portuguese bridge wraparound, near the pilothouse door for the intake vent. That way the shear has to be submerged to get flooding. Maybe I should have a cover plate that can be used to cover the walkway side openings for normal use, and for bad weather reposition those cover plates onto the outside vent openings.
Attached Thumbnails
Click image for larger version

Name:	IMG_0260 sml.jpg
Views:	93
Size:	97.8 KB
ID:	16432   Click image for larger version

Name:	IMG_0280 sml.jpg
Views:	81
Size:	99.0 KB
ID:	16434  
__________________
Brian
Insequent is offline   Reply With Quote
Old 02-08-2013, 05:30 PM   #47
Guru
 
Phil Fill's Avatar
 
City: Everett Wa
Country: US
Vessel Name: Eagle
Vessel Model: Roughwater 58 pilot house
Join Date: Oct 2007
Posts: 2,919
Stabilization might be needed more the last leg of the trip when the boat is the lightest and the tanks are empty. Estimate 5 to 10,000 lbs less at or below the center of gravity. However, it is my believe a boat should be stable with out stabilizers, which most pleasure boats are not. Many blue water sail boats and power boat do not have stabilization. Stabilization makes the ride more comfortable, decrease the angle of the roll, but does NOT increase the boats stability. For a blue water better to increase the boat stability, than to add stabilization.

Flooding maybe more of a concern than max roll angle. Vents and/or ports should be water tight and/or high above the water line. Large windows should be strong and/or additional protected from the out side. Every winter I screw/fasten 3/8 plexaglass to the salon windows teak wood frame with weather stripping to keep the rain off the windows and reduce the air draft, so they are air/water tight.


Most ocean crossing vessels have a rounded stern, so the following seas will pass around/under the hull with no or slotted swim deck the water can pass through. The stern should have reasonable size scuppers to take away/ drain the deck. The helm/pilot house should be protected by a high bow, Portuguese bridge and/or back toward the stern. The ride is better if the pilot house/helm is low and/or back toward the stern.

Range of 2,400 NM if crossing the Pacific is a concern. Not many motor boats under 60 ft have the range, so additional fuel would have to be carried. The fuel should be stored low, secure so it does not effect the stability. There should be back up for major systems, engines/get home, electronics, gen sets, sanitation, refrigeration, bilge pumps, water etc. Most boats do not have the redundancy and back up.

Like I said the first step for me is to get weaned away from the dock.


Phil Fill is offline   Reply With Quote
Old 02-09-2013, 06:14 AM   #48
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 16,531
Few trawler style boats will worry about being knocked over.

Its that big wave flopping on the deck and smashing into the PH that is a worry.
FF is offline   Reply With Quote
Old 02-09-2013, 11:03 AM   #49
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 6,372
Quote:
Originally Posted by Insequent View Post
I've only read part of these - thanks for the list. I definitely want some miles logged in PNW before leaving.

The reason I suggest going to Barkley Sound Via Straits of Juan de Fuca is it is more akin to doing the West Coast run south as to compared to the usually more benign conditions through the inner channels. Once you make it to Barkley, you can then decide if you want to go further North on the outside to test the boat and crew and end up at the Cape Scott juncture across Queen Charlotte Sound into the inner channels.

A great blog site in this regard is James Hamilton's first major ride North in his new, at that time, N52. He said "lets see what it can do" and went straight up the outside from Seattle to Prince William Sound. He and his N52 are now in Hawaii. Hamilton's cruising guides for the lesser known parts of the PNW are quite good.
sunchaser is online now   Reply With Quote
Old 02-09-2013, 11:07 AM   #50
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 6,372
Quote:
Originally Posted by FF View Post
Few trawler style boats will worry about being knocked over.

Its that big wave flopping on the deck and smashing into the PH that is a worry.
A big following sea and losing rudder control is more of a concern IMHO. Storm windows and/or thicker glass can alleviate the points you bring up.
sunchaser is online now   Reply With Quote
Old 02-09-2013, 01:24 PM   #51
Guru
 
Tad Roberts's Avatar
 
City: Flattop Islands
Country: Canada
Vessel Name: Blackfish
Vessel Model: custom
Join Date: Dec 2012
Posts: 707
Quote:
Originally Posted by Insequent View Post
Tad - if you are too busy that's fine. Lets see in a couple of months.
On my 'to do' list is to measure the hull lines .... Doesn't seem too difficult, just a bit painstaking so I'm procrastinating.
Not difficult at all, just requires a bit of care. You need a string that's longer than the boat, some painters masking tape, 25' tape measure, a medium length carpenters level, sharpi marker, plumb bob, and a clipboard with pen and paper. A nice tool is a self-leveling cross-line laser level. Some places rent these or you can buy one for about $150 plus a mounting pole. A nice afternoon and a willing helper....you're set.

On your boat you have two surfaces to measure, the bottom (horizontal) and the topsides and bow (vertical). Two separate methods are used. The string is stretched out tight parallel to the keel at 18" off centerline on the side you will measure (only do one side of the boat). It can be at any height that's convenient but at least 10-12" below the hull bottom. Use the tape to mark stations every 2.5' or 3' from bow to stern. Mark those stations "A" through whatever.

The string is your "base" line and positioned at "base" vertical height. You will measure everything relative to the baseline and base height. I usually set up level planks or blocking beyond the ends of the boat and just drive some nails in these to tie the string to. The base string will move outboard in even increments (say 12 or 18") after each buttock line measurement.

So to start the measuring you work along your base string from one end to the other, taking measurements from the string (baseline) up vertically to the hull surface and recording them (this is part of the reason for the helper). The hand level or plumb bob are used in conjunction with the tape measure to get a vertical measurement. If you like you can mark the stations on the hull using the hand level, eyeball, and sharpi.

Do three or four buttock lines in this way, moving the base string outboard after each series of measurements along the boat. The last series of bottom measurements will be of the chine or chines. Use the plumb bob to get widths of the chine from your base line, and then have the helper hold the tape on the chine while you use the level to get chine height above base.....

Then switch to horizontal measure mode. In this case the string moves vertically outside the boat (still parallel with the keel line) in steps that represent waterlines. Using the level and tape measure from the string to hull surface at each station and work your way up to the sheer. Again use the plumb bob held by your helper along the sheer to get width and height from the base line. The topsides is where the cross line laser is nice, it projects a line of light horizontally (waterline) and vertically (base line) at the same time. Due to the hull curve you need to set it up twice, beyond the bow and stern, and raise it in increments just like the string.

That's a start.......

Quote:
For the pilothouse windows I had in mind a two part solution. First replacing with thicker laminated glass and second being able to fit a removable bracket that has a 4-6" pressure pad in the center of the window that can be tensioned up to a suitable level. It would absorb deflection of the glass when hit by a wave.
You still need an emergency cover if the window is blown out. The usual thing is an aluminum plate with a small cutout to look through. The hole can be pretty small, say 5" by 8" and you can still see, depending on how close you can get to the window. Use a piece of paper or cardboard to check.

Quote:
My engine vents are in the bulwark, not easy to extend in an elegant way at least. See pic. I could seal those and have the openings on the inside, along the deck walkway, or even on the portuguese bridge wraparound, near the pilothouse door for the intake vent. That way the shear has to be submerged to get flooding. Maybe I should have a cover plate that can be used to cover the walkway side openings for normal use, and for bad weather reposition those cover plates onto the outside vent openings.
Higher and closer to the centerline is better. If they can go inside the bulwark and higher that's better than where they are. Downside is hot air/noise coming out into the cockpit which may be nasty.
Tad Roberts is offline   Reply With Quote
Old 02-09-2013, 01:37 PM   #52
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Country: USA
Vessel Name: Carquinez Coot
Vessel Model: 2011 Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 10,265
My (louvered) engine vents are on the pilothouse sides. I suppose a thin, bottomless "boxes" could be installed to reduce possible water entering during heavy seas.

__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 02-09-2013, 04:30 PM   #53
Senior Member
 
magicbus's Avatar
 
Join Date: Nov 2010
Posts: 460
It is interesting that your air intakes are located outboard and not inboard along the existing walkaround.

Dave
__________________
Barnegat Light NJ or Nantucket MA
magicbus is offline   Reply With Quote
Old 02-09-2013, 04:55 PM   #54
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 3,801
Just scanned this thread, didn't notice mention on Ben Gray and his Diesel Duck that pulled it off a few years ago, using an unusual route;

Home
__________________
George

"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
caltexflanc is offline   Reply With Quote
Old 02-09-2013, 05:30 PM   #55
Guru
 
Codger2's Avatar
 
City: San Diego
Country: US
Vessel Name: "Sandpiper"
Vessel Model: 2006 42' Ocean Alexander Sedan
Join Date: Oct 2007
Posts: 5,421
Quote:
Originally Posted by sunchaser View Post
A big following sea and losing rudder control is more of a concern IMHO.
Mine too! (If I were ever to do that kind of cruising, which I'm not.)
__________________
Codger2

My passion for improving my boat(s) exceeds my desire to constantly cruise them.
Codger2 is offline   Reply With Quote
Old 02-09-2013, 05:48 PM   #56
Guru
 
Codger2's Avatar
 
City: San Diego
Country: US
Vessel Name: "Sandpiper"
Vessel Model: 2006 42' Ocean Alexander Sedan
Join Date: Oct 2007
Posts: 5,421
Quote:
Originally Posted by markpierce View Post
My (louvered) engine vents are on the pilothouse sides.
As are mine...Also, no port lights in hull.
Attached Thumbnails
Click image for larger version

Name:	SeaHorse.jpg
Views:	96
Size:	124.8 KB
ID:	16463   Click image for larger version

Name:	SeaHorse 2.jpg
Views:	90
Size:	98.9 KB
ID:	16464  
__________________
Codger2

My passion for improving my boat(s) exceeds my desire to constantly cruise them.
Codger2 is offline   Reply With Quote
Old 02-09-2013, 05:55 PM   #57
Guru
 
Tidahapah's Avatar
 
City: Mooloolaba
Country: Australia
Vessel Name: Tidahapah
Vessel Model: Bert Ellis Timber motor cruiser
Join Date: Oct 2007
Posts: 1,779
Guys,
I have made a copy of Jims book Nordlys around the world.
It is 92 PDF pages so a bit big to transport electronically.
I could probably put it on disc and post it out or does anyone know a way to reduce the size of the files to send it electronically.
Cheers
benn
__________________
"When I die I hope my wife doesn't sell my toys for what I told her I paid for them"
Money: It's made round to go round , not flat to stack.
"Get out and do it"
Tidahapah is offline   Reply With Quote
Old 02-09-2013, 08:11 PM   #58
Guru
 
Insequent's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 1,426
Quote:
Originally Posted by Tad Roberts View Post
Not difficult at all, just requires a bit of care. You need a string that's longer than the boat, some painters masking tape, 25' tape measure, a medium length carpenters level, sharpi marker, plumb bob, and a clipboard with pen and paper. A nice tool is a self-leveling cross-line laser level. Some places rent these or you can buy one for about $150 plus a mounting pole. A nice afternoon and a willing helper....you're set.

On your boat you have two surfaces to measure, the bottom (horizontal) and the topsides and bow (vertical). Two separate methods are used. The string is stretched out tight parallel to the keel at 18" off centerline on the side you will measure (only do one side of the boat). It can be at any height that's convenient but at least 10-12" below the hull bottom. Use the tape to mark stations every 2.5' or 3' from bow to stern. Mark those stations "A" through whatever.

The string is your "base" line and positioned at "base" vertical height. You will measure everything relative to the baseline and base height. I usually set up level planks or blocking beyond the ends of the boat and just drive some nails in these to tie the string to. The base string will move outboard in even increments (say 12 or 18") after each buttock line measurement.

So to start the measuring you work along your base string from one end to the other, taking measurements from the string (baseline) up vertically to the hull surface and recording them (this is part of the reason for the helper). The hand level or plumb bob are used in conjunction with the tape measure to get a vertical measurement. If you like you can mark the stations on the hull using the hand level, eyeball, and sharpi.

Do three or four buttock lines in this way, moving the base string outboard after each series of measurements along the boat. The last series of bottom measurements will be of the chine or chines. Use the plumb bob to get widths of the chine from your base line, and then have the helper hold the tape on the chine while you use the level to get chine height above base.....

Then switch to horizontal measure mode. In this case the string moves vertically outside the boat (still parallel with the keel line) in steps that represent waterlines. Using the level and tape measure from the string to hull surface at each station and work your way up to the sheer. Again use the plumb bob held by your helper along the sheer to get width and height from the base line. The topsides is where the cross line laser is nice, it projects a line of light horizontally (waterline) and vertically (base line) at the same time. Due to the hull curve you need to set it up twice, beyond the bow and stern, and raise it in increments just like the string.

That's a start.......

You still need an emergency cover if the window is blown out. The usual thing is an aluminum plate with a small cutout to look through. The hole can be pretty small, say 5" by 8" and you can still see, depending on how close you can get to the window. Use a piece of paper or cardboard to check.

Higher and closer to the centerline is better. If they can go inside the bulwark and higher that's better than where they are. Downside is hot air/noise coming out into the cockpit which may be nasty.
Thanks for your comments and directions Tad. I will return to the boat in early March and get busy then!
__________________
Brian
Insequent is offline   Reply With Quote
Old 02-09-2013, 08:22 PM   #59
Guru
 
Insequent's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 1,426
Quote:
Originally Posted by Tidahapah View Post
Guys,
I have made a copy of Jims book Nordlys around the world.
It is 92 PDF pages so a bit big to transport electronically.
I could probably put it on disc and post it out or does anyone know a way to reduce the size of the files to send it electronically.
Cheers
benn
its very difficult to reduce the size of a pdf. If scanning, set a low resolution and if given options do black & white, text only. Test some settings first. If converting text files to pdf there is less flexibility but that works well where there are few pictures.

The other option is to upload it onto a site designed for file sharing. There are various business oriented solutions, but I've not used them. I'll pm you my address, if you can post it that's great.
__________________
Brian
Insequent is offline   Reply With Quote
Old 02-09-2013, 09:25 PM   #60
Guru
 
Northern Spy's Avatar
 
City: Powell River, BC
Country: Canada
Vessel Name: Northern Spy
Vessel Model: Nordic Tug 26
Join Date: Feb 2012
Posts: 2,668
Quote:
Originally Posted by Tidahapah View Post
Guys,
I have made a copy of Jims book Nordlys around the world.
It is 92 PDF pages so a bit big to transport electronically.
I could probably put it on disc and post it out or does anyone know a way to reduce the size of the files to send it electronically.
Cheers
benn
Adobe X Pro has a function in which you can save as a "small" pdf.
__________________

Northern Spy is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 08:11 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012