Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 07-03-2014, 09:29   #46
Moderator
 
Hudson Force's Avatar

Cruisers Forum Supporter

Join Date: Nov 2008
Location: Lived aboard & cruised for 45 years,- now on a chair in my walk-in closet.
Boat: Morgan OI 413 1973 - Aythya
Posts: 7,894
Images: 1
Re: How Tall is Your Mast?

Quote:
Originally Posted by thomm225 View Post
Most folks just go to sailboatdata.com and get that info. It gives the I, J, P, and E for just about every sailboat you can think of:

Sailboatdata.com is the worlds largest sailboat database. You can figure clearance from that.

Sail Measurement Assistance
Total vertical clearance for my boat is not shown on these sites. Data like I, J, P & E are not calculated from the waterline or the top of the masthead. I would think that people using these numbers could be led to hitting bridges!

Ah, but I see that you say, "you can figure your clearance from that." I sometimes pass under bridges when I know my VHF antennae will be rubbing the underside of the bridge. People should be able to get an accurate number by direct measurement and not guess what remains above the head of the sail or from the foot to the waterline.

Thanks, Thomm225, for a reminder of this data site, but all you passing under bridges better obtain the full numbers!
__________________

__________________
Take care and joy, Aythya crew
Hudson Force is offline   Reply With Quote
Old 07-03-2014, 10:23   #47
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: How Tall is Your Mast?

Quote:
Originally Posted by markpierce View Post
Are you sure? Think of the thousands who didn't respond to my inquiry.
Actually, close to 6 billion people did not respond to your inquiry, so you are correct - nobody knows the height of the mast of their boat except for the very few who have posted here, and they are an anomaly in this regard.

Superb logic and reasoning!

Mark
__________________

__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 07-03-2014, 11:15   #48
Registered User
 
thomm225's Avatar

Join Date: Aug 2011
Location: Hampton Roads
Boat: 1974 Bristol 27
Posts: 3,484
Re: How Tall is Your Mast?

Quote:
Originally Posted by CaptForce View Post
Total vertical clearance for my boat is not shown on these sites. Data like I, J, P & E are not calculated from the waterline or the top of the masthead. I would think that people using these numbers could be led to hitting bridges!

Ah, but I see that you say, "you can figure your clearance from that." I sometimes pass under bridges when I know my VHF antennae will be rubbing the underside of the bridge. People should be able to get an accurate number by direct measurement and not guess what remains above the head of the sail or from the foot to the waterline.

Thanks, Thomm225, for a reminder of this data site, but all you passing under bridges better obtain the full numbers!
Well I guess I was giving folks too much credit.

I figured a person could look at the diagrams provided and measure from the waterline to deck and add to the I measurement. (and possibly add in a little fudge facter.

I guess math really is a problem here in the United States.
__________________
thomm225 is offline   Reply With Quote
Old 07-03-2014, 13:19   #49
Senior Cruiser
 
Jim Cate's Avatar

Cruisers Forum Supporter

Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 11,471
Re: How Tall is Your Mast?

Quote:
Originally Posted by thomm225 View Post
Well I guess I was giving folks too much credit.

I figured a person could look at the diagrams provided and measure from the waterline to deck and add to the I measurement. (and possibly add in a little fudge facter.

I guess math really is a problem here in the United States.
Yes, that method will work... if you are SURE that you own a totally original production boat, and that the figures posted are really correct. I've found that boats, especially older ones, often are not quite the same as when they left the builder's yard, and that there are even variations within a production run. And there are still non-production boats in use (like Mark's).

Apparently many of the responders in this thread go under bridges where their clearance is measured in inches. If I was one of them, I would want to do the physical measurement. Twice!

It isn't all that hard to do, so why not?

Jim
__________________
Jim and Ann s/v Insatiable II , lying Port Cygnet, Tasmania once again
Jim Cate is offline   Reply With Quote
Old 07-03-2014, 14:33   #50
Moderator
 
Hudson Force's Avatar

Cruisers Forum Supporter

Join Date: Nov 2008
Location: Lived aboard & cruised for 45 years,- now on a chair in my walk-in closet.
Boat: Morgan OI 413 1973 - Aythya
Posts: 7,894
Images: 1
Re: How Tall is Your Mast?

Yeah, it's that "fudge factor" instead of the direct measurement that I would consider the math deficiency. I want the direct measurement to the top of the lens on my masthead anchor light while I'm in the bosun's chair. I've seen different numbers in print for the dimensions of my 1973 ketch.
__________________
Take care and joy, Aythya crew
Hudson Force is offline   Reply With Quote
Old 07-03-2014, 14:39   #51
Registered User
 
thomm225's Avatar

Join Date: Aug 2011
Location: Hampton Roads
Boat: 1974 Bristol 27
Posts: 3,484
Re: How Tall is Your Mast?

Quote:
Originally Posted by CaptForce View Post
Yeah, it's that "fudge factor" instead of the direct measurement that I would consider the math deficiency. I want the direct measurement to the top of the lens on my masthead anchor light while I'm in the bosun's chair. I've seen different numbers in print for the dimensions of my 1973 ketch.
Ok, understood.

I went under a 40' bridge recently. The I measurement on my boat is 30'5' and my freeboard is maybe 3-4' but I still inched up to that bridge very slowly...............then went under. My VHF antenna cleared it also but it seemed close.
__________________
thomm225 is offline   Reply With Quote
Old 07-03-2014, 15:19   #52
Moderator
 
Hudson Force's Avatar

Cruisers Forum Supporter

Join Date: Nov 2008
Location: Lived aboard & cruised for 45 years,- now on a chair in my walk-in closet.
Boat: Morgan OI 413 1973 - Aythya
Posts: 7,894
Images: 1
Re: How Tall is Your Mast?

Quote:
Originally Posted by thomm225 View Post
...............then went under. My VHF antenna cleared it also but it seemed close.
I remember a time years ago on another boat when Nancie dropped me off at the bridge fender so I could climb up to the catwalk under the span while she backed our boat through. We wanted to move under in reverse for an easy abort. The fixed bridge was charted at 45'MHW and we were 46'6" and at mid-tide. I noticed that, of the four steel I-beams under the bridge, the third one was at an angle that made the lowpoint. With a bit of a chop on the water surface it was hard to tell wether we would clear the third I-beam, but I waved her through and we did not touch. I made careful notes of the fender boards at that time. I knew I needed to have the two higher port fender boards out of the water when southbound and the center of the bolt head on the second starboard fender board at the water line when northbound. With the binoculars ready we either stopped for tide or proceeded at this bridge for years. Knowing your limits is freedom!

BTW, that's the Shands Bridge on the south side of Green Cove Springs, Florida. I can't go south of there now on the boat I've had since 1985. There are some beautiful places down there with clear springs and alligators laying on the banks. I miss them!
__________________
Take care and joy, Aythya crew
Hudson Force is offline   Reply With Quote
Old 07-03-2014, 16:54   #53
Registered User
 
Safari38LH's Avatar

Join Date: Dec 2010
Location: Marion, Ma
Boat: Little Harbor 38
Posts: 259
Re: How Tall is Your Mast?

I noticed a lot of replies have the word "about" in them. How many know the exact height above water of their mast? Personally, that's something I want to know. There are places like the Cape May canal at 55ft that can save you tons of time if you can fit under.' My mast us supposed to be 56' 6". That's what the specs from the past buyer said. Can I fit under the Cape May bridge at low tide? Do I trust the specs that came with the boat - fourth owner. I would not and did not try it without knowing the exact height first. I'm also not so sure running a tape up a halyard and to the water will give you an exact measurement.
__________________
Safari38LH is offline   Reply With Quote
Old 07-03-2014, 17:04   #54
Moderator
 
Hudson Force's Avatar

Cruisers Forum Supporter

Join Date: Nov 2008
Location: Lived aboard & cruised for 45 years,- now on a chair in my walk-in closet.
Boat: Morgan OI 413 1973 - Aythya
Posts: 7,894
Images: 1
Re: How Tall is Your Mast?

I'm somewhat angered by the lack of clearance cards on both sides of the two Cape May Canal bridges. I have waited at anchor in the Cape May Canal and then later passed with my VHF antennae scraping the underside of the bridge. All this, and my mast height is lower than the stated MHW clearance of the bridges!
__________________
Take care and joy, Aythya crew
Hudson Force is offline   Reply With Quote
Old 07-03-2014, 17:06   #55
Marine Service Provider
 
Scott Berg's Avatar

Join Date: Jul 2011
Location: Aboard
Boat: Seaton 60' Ketch
Posts: 959
Re: How Tall is Your Mast?

Mine is 74' to the top of the mast and lights, 78' to the top of the antenna; not that hard to measure. Pull up a halyard to the masthead block (spinnaker halyard is easiest); measure to deck...
Then measure deck to waterline when tanks are half full...

Add the two...
Add the height of anything on top of your mast...

Total is height above water.
__________________
Scott Berg
WAĜLSS
SV CHARDONNAY
Scott Berg is offline   Reply With Quote
Old 07-03-2014, 17:49   #56
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: How Tall is Your Mast?

Quote:
Originally Posted by Safari38LH View Post
I noticed a lot of replies have the word "about" in them. How many know the exact height above water of their mast? Personally, that's something I want to know. There are places like the Cape May canal at 55ft that can save you tons of time if you can fit under.' My mast us supposed to be 56' 6". That's what the specs from the past buyer said. Can I fit under the Cape May bridge at low tide? Do I trust the specs that came with the boat - fourth owner. I would not and did not try it without knowing the exact height first. I'm also not so sure running a tape up a halyard and to the water will give you an exact measurement.
If you need to know the height of your mast to enable you to clear a bridge, the best way is to post a random picture of your boat here and let us guess at its height.

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 07-03-2014, 18:45   #57
Registered User
 
markpierce's Avatar

Join Date: Aug 2010
Location: Central California
Boat: M/V Carquinez Coot
Posts: 3,416
Re: How Tall is Your Mast?

I measured the boat today. From waterline to top of mast with lightning rod is 31'6". I'll use 32' to be on the safe side.

In the early 1960s my father sailed his Columbia Defender sloop under the Oakland end of the Bay Bridge. The wind vane fell into the cockpit. It had hit the bottom of the bridge. Good thing we weren't further east where the bridge is even lower.

Cleared it (GG Bridge):

__________________
Kar-KEEN-ez Koot
markpierce is online now   Reply With Quote
Old 07-03-2014, 19:03   #58
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: How Tall is Your Mast?

Quote:
Originally Posted by markpierce View Post
I measured the boat today. From waterline to top of mast with lightning rod is 31'6". I'll use 32' to be on the safe side.

In the early 1960s my father sailed his Columbia Defender sloop under the Oakland end of the Bay Bridge. The wind vane fell into the cockpit. It had hit the bottom of the bridge. Good thing we weren't further east where the bridge is even lower.

Cleared it (GG Bridge):


And that is a beautiful picture - looks like you just squeaked by...

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 07-03-2014, 20:32   #59
Registered User
 
Suijin's Avatar

Join Date: Feb 2013
Location: Annapolis MD; currently in Oriental NC
Boat: Valiant 40
Posts: 2,937
Re: How tall is your mast?

Quote:
Originally Posted by CaptForce View Post
My mast is 57'6" high, but my vertical clearance above the water is 54'6".
So the foot of your mast is 3' below the waterline...and your mast is 57'6" long?

Just checking. I've never tried going under the Cape May bridge, with a air draft of 55' plus antenna. Maybe I can try it with a spring neap tide. Going around those shoals adds a couple of hours :\
__________________
Suijin is online now   Reply With Quote
Old 07-03-2014, 22:07   #60
Senior Cruiser
 
44'cruisingcat's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 7,459
Images: 69
Re: How Tall is Your Mast?

60' with VHF antenna.
__________________

__________________
44'cruisingcat is offline   Reply With Quote
Reply

Tags
mast

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Attaching a Removable Inner Forestay to the Mast Weyalan Deck hardware: Rigging, Sails & Hoisting 32 21-12-2013 07:05
Stepping O'day 17 Daysailer Mast Markjensen Monohull Sailboats 3 04-11-2012 19:14
Installing Mast Boot with No Mast Collar ? MikeTurner Deck hardware: Rigging, Sails & Hoisting 1 12-10-2011 09:40
Mast Came Down, Must Repair Acedude Construction, Maintenance & Refit 7 30-08-2011 14:01
For Sale: 58' Tall Mast / 34' Tall Mast thesparrow Classifieds Archive 0 13-06-2011 13:07



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 10:25.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.