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vincent
11-14-2008, 04:39 AM
Hello
first a question - how do you call a "Box" where the Keel goes inside and when sailing you put it out?

the second question - how do you Fix this BOX on the boat - is it enough to screw it to the bottom or keel pattern. Are there some Picture to show me?

Thanks a lot for feedbacks

Vincent

MiddleAgesMan
11-14-2008, 07:33 AM
You are describing a centercase, also called centerboard case, also daggerboard case, etc.

You will need more than screws to attach it or it will leak. A good marine adhesive would be best, bedding compound at the least.

The centercase also needs to be well supported at the top.

outofthenorm
11-14-2008, 09:52 AM
There are lots of methods, but it will depend on how the boat is built. The solutions you would use for plywood might be different from what would work best for a traditional build. Can you tell us more about it? Is it a new build, or a repair? Do you have pictures?

- Norm

vincent
11-14-2008, 09:55 AM
@outofthenorm (http://www.woodenboat.com/forum/member.php?u=9857)
a lots of picute - follow the link Lumberyard Skiff
it is in german but the picture are international!

vincent

outofthenorm
11-14-2008, 10:46 AM
Flat bottom skiff is the easiest installation of all. Here's a diagram - see if it explains what you need. If not, it's a good start.

The bedlogs extend the whole length of the case or longer.
The posts that form the ends of the case can either be left long and go through the slot (cut them off flush with the bottom) or they can be cut shorter to be the same depth as the case itself. The first way is stronger - The second way makes it easier to seal the end grain of the posts.

http://web.mac.com/outofthenorm/iWeb/Site%202/Library_files/Centrecase.jpg

- Norm

outofthenorm
11-14-2008, 10:53 AM
Here's an alternative for the sides of the case - extended to cover the end grain of the cross-planking where it's cut for the slot.

http://web.mac.com/outofthenorm/iWeb/Site%202/Library_files/Centrecase%202.jpg

Thorne
11-14-2008, 11:06 AM
Wow -- OutoftheNorm has really got it illustrated well!

Don't know if any of John Gardner's books have been printed in other languages, but you might look around and see what's available in Switzerland. If possible, his _Dory Book_ would be a good choice as it clearly illustrates centerboard and centerboard case construction, as well as various small boat sailing rigs, rudder designs, etc.

Here's a link to my dory restoration page -- the photos of my centerboard and case may be of assistance to you.
http://www.luckhardt.com/dory1.html

http://www.luckhardt.com/cb-case1.jpg http://www.luckhardt.com/cb-case3.jpg

http://www.luckhardt.com/brokenCB1.jpg

JimD
11-14-2008, 11:16 AM
It's also often called a 'trunk' as well as a 'case'.

vincent
11-24-2008, 07:10 AM
ok thanks for all information.
there are now two more questions,

how do you protected the wood between the two "sides of case"?
and how do you fix the joint between the sides and the Keel, it is a fix installation or possible to remove later?

thanks for all feedbacks
vincent

outofthenorm
11-24-2008, 09:47 AM
Vincent, the old way to protect the inside of the case is with paint, the new way is with epoxy and fibreglass, applied to the insides before assembly.

The whole case is permanently attached to the boat with either bolts or screws and your favourite glue - and it should all be built strong.

- Norm

Thorne
11-24-2008, 10:17 AM
I prefer a more flexible sealant for bedding / seating the centerboard case to the bottom planks - something like Vulken116 or 3M 4200. A more rigid glue like epoxy may crack and leak when you eventually hit ground with the centerboard down...

And use big screws coming up from underneath the bottom planks up into the bed logs or base of the centerboard case.

Again -- get a copy of John Gardner's THE DORY BOOK -- great illustrations on how to build and bed various centerboards and cases.

vincent
02-08-2009, 10:15 AM
@Thorne


I
Again -- get a copy of John Gardner's THE DORY BOOK -- great illustrations on how to build and bed various centerboards and cases.

Hello - this book cost arround 100 Dollar second hand. And as i saw it is not available as a new book.

And yes i am still building my boat - but the place i have to build it is still around 0 degree, so it is not possible to clue something, but to plane the wood keeps warm.

have a nice day
vincent

SMARTINSEN
02-08-2009, 10:33 AM
@Thorne



Hello - this book cost arround 100 Dollar second hand. And as i saw it is not available as a new book.

And yes i am still building my boat - but the place i have to build it is still around 0 degree, so it is not possible to clue something, but to plane the wood keeps warm.

have a nice day
vincent

About $30.00US and up here (http://www.alibris.com/booksearch?binding=&mtype=&keyword=gardner%2C+dory+book&hs.x=15&hs.y=15&hs=Submit) in the U.S., but I do not know about shipping to Europe. I have been considering purchasing this book myself.

vincent
02-08-2009, 10:58 AM
@smartinsen
thanks a lot - i Orderd it now!
vincent

vincent
02-10-2009, 10:11 AM
Hello Norm

... the new way is with epoxy and fibreglass, applied to the insides before assembly.
i have a question - how the wood is interacting between the Wood with epoxy and the plain wood.
have a nice day
vincent

Thorne
02-10-2009, 10:39 AM
Vincent -

You can also order used books from Abebooks.co.uk -
http://www.abebooks.co.uk/servlet/SearchResults?an=john+gardner&bt.x=0&bt.y=0&sortby=3&sts=t&tn=the+dory+book

The wood without epoxy will swell and shrink as it gets wet, but the wood coated with epoxy will remain the same size and dimensions. If your boat is not left in the water for long periods of time it shouldn't matter too much.

For example, on my 16' dory skiff the centerboard case ("box") is made from white oak, which is known for a lot of swelling and shrinking as it gets wet and dries out. It is painted with red lead primer and marine paint inside.

My centerboard is made from marine plywood and covered with epoxy and fiberglass cloth, and I've not had any problems with the clearance / space between centerboard and case even when the boat has been in the water for a week.