Boat Design Forums  |  Boat Design Directory  |  Boat Design Gallery  |  Boat Design Book Store  |  Thanks to Our Site Sponsors

Go Back   Boat Design Forums > Design > Boat Design
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 03-15-2010, 04:04 PM
Boston's Avatar
Boston Boston is offline
Senior Member
 
Join Date: Jul 2008
Rep: 1457 Posts: 3,355
Location: Denver Co
How Much Of A Cat Walk Do You Really Need

as some of you know I've been thinking retirement build for a while now and Im still working out a few things

one of which is how much actually foot room I need to run for and aft to handle lines when docking or to throw a life ring to the occasional numskull



how much room would you say was allowed between the edge of the deck cabin and the edge of the hull on old Widgeon pictured above

the boat is 46' and I believe has about a 12' beam

looks like not much
maybe a foot at best

and how much room would you folks think it should have ideally

thanks
B
__________________
I am skeptical of the deniers diatribe
Reply With Quote
  #2  
Old 03-15-2010, 07:41 PM
u4ea32's Avatar
u4ea32 u4ea32 is offline
Senior Member
 
Join Date: Nov 2005
Rep: 175 Posts: 378
Location: Los Angeles
On my boat, I've got 8 inches of deck, and that's plenty, because there is also a hand rail that is 12 inches high aft, increasing to 18 inches high forward. The low rail is kinda like a VERY effective toe rail: I can push my lower leg against it. I've got hand rails on the T top too, the T top is about 3 feet above the deck. Forward of the t-top, where I've only got the outboard handrail, the handrail is about 18 inches high.

I was quite surprised, but that little works great, even with that low of a hand rail.

The rail is really a very long pulpit (from the bow to about midship), and welded in one piece of stainless steel. So its quite sturdy, very little flex, load is spread all along it so I don't have a problem with the stanchion bases. Being stainless steel, it seems transparent from the helm -- while its almost directly on the horizon sometimes underway, I never notice that it obscures my vision.

Also, I spent a couple of weeks chartering a Nordic Tug 32 in Alaska. It had about 6 inches alongside the "wide body" main cabin. With the hand rails on top of the cabin, no rail outboard, it was possible but a bit dicey to move fore and aft along that cabin. The low outboard handrails on my boat make a big difference! Also, that two inches seemed to make a big difference.

By the way, that Widgeon is one beautiful boat!
__________________
David Smyth
Reply With Quote
  #3  
Old 03-15-2010, 09:46 PM
TollyWally TollyWally is offline
Senior Member
 
Join Date: Mar 2005
Rep: 418 Posts: 777
Location: Fox Island
More is better to a point, handrails make a huge difference. One hand for yourself, one hand for the ship etc. 12" is ample, 10" is adequate.

As a younger man I've gone forward on smaller boats, gillnetters, under extremely harrowing conditions. Falling into the water would most likely have been fatal, getting to the foredeck was not optional. Handrails are your friends. Something to take into consideration is how much the house etc. slopes inward and if you can lean in over the top of it etc. As I age up I appreciate wider margins. What feels good at 25 is only adequate at 50.

For a retirement build I'd err on the side of wider. Losing 4 or 5 inches in the trunk cabin or what have you maynot be noticed after a bit. Feeling good walking up to the foredeck will give you a smug feeling of satisfaction every time you do it. After all isn't that the point of a custom build? getting the personal details customized to your criteria rather than one size fits all.
__________________
If this is tourist season, why can't we shoot them?
Reply With Quote
  #4  
Old 03-15-2010, 11:01 PM
Frosty's Avatar
Frosty Frosty is online now
Senior Member
 
Join Date: May 2002
Rep: 1693 Posts: 5,863
Location: Thailand
Bos that looks like a Thames gentlemans yacht. There is lots of them around Windsor etc and on the broads of UK. Its a river boat.

Wood being wood a lot are moored up permanently as house boats.
Reply With Quote
  #5  
Old 03-15-2010, 11:03 PM
Boston's Avatar
Boston Boston is offline
Senior Member
 
Join Date: Jul 2008
Rep: 1457 Posts: 3,355
Location: Denver Co
max beam is 12' and the length is 48
I got the profile the way I want it and a preliminary weight budget works out as well as the power plant I intend to use
displacement is ~25,000lbs
construction is cold molded hull chine form with a modified sharpie type bottom



reason I ask about the cat walk is that need to start the plan view and obviously its decision time on the width of the walks

I had planned on one foot with rails

oh
the rails are not shown in that drawing but they come straight back off the line of the raised deck and continue around the entire deck structure

thanks for the tips kids

B
__________________
I am skeptical of the deniers diatribe
Reply With Quote
  #6  
Old 03-15-2010, 11:06 PM
Boston's Avatar
Boston Boston is offline
Senior Member
 
Join Date: Jul 2008
Rep: 1457 Posts: 3,355
Location: Denver Co
ya I increased the free board and have a few other tricks up my sleeve for making a better coaster

besides I might just end up living in a river at this rate

funny thing is how shallow the draft works out to

at 25000 its got all of about 10~12" draft
48 long 12 wide .75 one way and .9 the other
works out to about 9 inches in dead calm water
__________________
I am skeptical of the deniers diatribe
Reply With Quote
  #7  
Old 03-16-2010, 02:08 AM
Frosty's Avatar
Frosty Frosty is online now
Senior Member
 
Join Date: May 2002
Rep: 1693 Posts: 5,863
Location: Thailand
Why don't you copy the bottom of a good known sea boat like a Grand Banks.
Reply With Quote
  #8  
Old 03-16-2010, 02:13 AM
Boston's Avatar
Boston Boston is offline
Senior Member
 
Join Date: Jul 2008
Rep: 1457 Posts: 3,355
Location: Denver Co
cause I want a shallow draft so I can sneak up river in a pinch

the Dashew once again has a nice shallow draft and a keel bulb for balance on blue water

Im thinking of a cross between Ted Brewer modified sharpie and the Dashew
but let just get the right cat walk for now
Ill detail the bottom once I get a few more basics worked out
__________________
I am skeptical of the deniers diatribe
Reply With Quote
  #9  
Old 03-16-2010, 03:54 AM
mark775
Guest
 
Posts: n/a
If you will leave the marina, you will appreciate side decks that you don't need to crab or slither to negotiate. Boats with big cabins are gay - What's the cut of your jib, Bos?
Kidding, I know. Now put some beefy rails and some deck space. Side decks need at least the width of one's hips. The best boats allow full stride running with a net containing three silvers behind fishermen at the rail. The best boats make room for friends in a wheel-chair to go forward and watch the orca, too. Skiffs wedged in there, piles of deer carcasses, room to pass a barbeque to the boat that's cookin' tonight, room to get on the hip of the broken boat ya gotta' tow, room to lay your .270 on the rail as you kneel on one knee, all need to be accomodated. Those East Coast lobster boats (ugly as they are) got this right - if it's a narrow boat, put the cabin to one side BUT ALWAYS LEAVE A SIDE DECK! Anything else is a compromise - mine has mini side decks (18") and I curse them. I cannot go forward without thinking of my cabin (10' 10" wide) on a boat 16' wide.
I hope I may have convinced you tp go an inch or two wider!
Reply With Quote
  #10  
Old 03-16-2010, 05:46 AM
rasorinc rasorinc is offline
Senior Member
 
Join Date: Nov 2007
Rep: 687 Posts: 1,175
Location: Knoxville, Tennessee
Bos, this photo shows a boat similar to what yours looks like and shows an ample walkway. http://www.boatdesign.net/gallery/sh...hp/photo/12349
Reply With Quote
  #11  
Old 03-16-2010, 06:09 AM
daiquiri's Avatar
daiquiri daiquiri is offline
Engineering and Design
 
Join Date: May 2004
Rep: 2574 Posts: 2,731
Location: Italy (Garda Lake) and Croatia (Istria)
I would say that too little is not good, and too much is not good either. You do need a space to move comfortably fore and aft, but your feet also need lateral walls to push against when waves start rockin' and rollin' your boat. The numbers will depend on your body size.

By the way, that's one really handsome boat.
Reply With Quote
  #12  
Old 03-16-2010, 12:41 PM
Boston's Avatar
Boston Boston is offline
Senior Member
 
Join Date: Jul 2008
Rep: 1457 Posts: 3,355
Location: Denver Co
thanks for all the input folks
with this kind of help I'll get this thing right first time
which is kinda the big goal

if it were a house I'd say 3' on all walkways or better
but on a boat who knows

ok
Mark has a point
silly as it sounds I need to be able to drag supplies on and off the boat without to much trouble and without beating up the brightwork
I was originally thinking 12~18" but 2' would be ideal

so now I start thinking of beam to length ratio
boat is 48 long so I can have 12' beam and still be at 4:1
which isn't great but isn't to bad for efficiency
( water line its 10 which gives it a better ratio of 4.8:1. I want this thing as narrow as possible )

the aft cabin is big 18'6" long as pictured
ceiling height varies from 6'6" to 7'2"
width is yet to be determined but I was hoping for 10'

wheel house is 13'+ long as pictured
ceiling height varies from 6'6" to 7'2"
width I was hoping to be the same as the aft cabin but I really want that 2' walk which means the wheel house is 8' wide and the aft cabin will want to be wider than the wheel house

oh
at 8 feet the wheel house would be one cramped office what with the two stairways leading forward and aft

and so that is the root of my question

if I made the cat walk only 1' I could have my 10 wide wheel house and after cabin
but the issues Mark brings up would not be being addressed and his is in the end right
would drive me nuts eventually to have no room like that

if I made the cat walk 2' wide I end up with a wheel house thats fine as a wheel house but sucks as an office space
I want a desk and computer set up along with a few chairs as well as a pilot station and nave area

still working on it

thanks for all the tips

B

oh
once I get a few plan views worked out Ill post them but for now that elevation is the only thing I feel good enough about to show the group
its been through the ringer and Ive worked it out to all kinds of different scales but at 48 it seems to fit best both the budget and the look I was after

Im beginning to think 1' is all I will be able to manage

if I have to haul a barbecue or take a shot off the deck I can always either go through the cabin or sit on the aft cabin roof
I made it ass high so folks could sit on it
even thought maybe I'd but a back rest and cushions up there either side of the Jolly boat

cheers
B

oh hey Mark
there gotta be a gun rack with the 7 mil ultra mag in it in the back window
thought you might get a bang out of that

back when I was a kid we always has a riffle in the back window
hows Alaska on me sporting a weapon but the way?
if Im in Alaska I plan on doing some hunting

oh and hey Tad
funny how our numbers worked out so close
length draft beam even the displacement I got close

Im working on righting moment and that weight budget you spoke about by the way

cheers and thanks for all the help folks its greatly appreciated
__________________
I am skeptical of the deniers diatribe
Reply With Quote
  #13  
Old 03-16-2010, 01:16 PM
Tad's Avatar
Tad Tad is offline
Yacht Designer
 
Join Date: Mar 2002
Rep: 2037 Posts: 1,719
Location: Gabriola Island, B.C. Canada
Quote:
Originally Posted by Boston View Post
how much room would you say was allowed between the edge of the deck cabin and the edge of the hull
NONE !! http://www.passagemakerlite.com/desi...gemakerlite-46

Oh ya......get rid of the ruler when drawing boats......
Reply With Quote
  #14  
Old 03-16-2010, 01:20 PM
Tad's Avatar
Tad Tad is offline
Yacht Designer
 
Join Date: Mar 2002
Rep: 2037 Posts: 1,719
Location: Gabriola Island, B.C. Canada
Quote:
Originally Posted by Boston View Post

the Dashew once again has a nice shallow draft and a keel bulb for balance on blue water
Where on earth did this idea come from?

yachting_review.pdf
Reply With Quote
  #15  
Old 03-16-2010, 01:47 PM
Boston's Avatar
Boston Boston is offline
Senior Member
 
Join Date: Jul 2008
Rep: 1457 Posts: 3,355
Location: Denver Co
woops
your right I was thinking of a different designer

my bad

well I was thinking also if I made the aft cabin full width and the wheel house only with a cat walk
but then tying off your running through the boat rather than over decks
also in the event of trouble having good maneuverability round the decks might come in dam handy

its posing quite the dilemma though as I really want a workable office space in the wheel house

something tells me you and mark could really have it out over this one

deck space is a must at least for me
that area forward is for laying out goofing off
an area aft would be equally as nice for sitting down to a few beers and a barbecue
access between the two over decks would be great if I can work it out

Ive considered going with a shallower draft and a wider boat but that screws up a lot of the numbers on stability
__________________
I am skeptical of the deniers diatribe
Reply With Quote
Reply



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Walk Thru Transom pilot8251w Fiberglass and Composite Boat Building 2 05-05-2009 01:52 PM
Doing a walk thru transom Ctskip Fiberglass and Composite Boat Building 1 05-10-2006 02:35 AM
open the transom for a walk-thru Ctskip Boatbuilding 0 05-08-2006 05:00 PM
Doing a walk-thru transom Ctskip Sailboats 1 05-08-2006 06:50 AM
Prop-walk rod fox Propulsion 7 11-08-2004 12:34 PM


All times are GMT -5. The time now is 11:42 PM.


Powered by: vBulletin Copyright ©2000 - 2012, Jelsoft Enterprises Ltd.
Web Site Design and Content Copyright ©1999 - 2012 Boat Design Net