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jcorlissf
04-05-2010, 05:38 PM
currently i'm building up the deadwood for my 25 foot coastal cruiser out of white oak. with a limited supply of white oak and limited funds as well i came across a sawyer who would gladly saw up a log for me to suit my needs. while my needs are relatively small, he also said there were plenty of slabs laying about and that would certainly help save some money. i'm building the deadwood in 2 in lifts and i came across a couple of slabs which would cover everything. having never dealt with green lumber before the numerous surface checks on the upward faces of the slabs frightened me away once. but time passed and i found myself returning to investigate once more. the side of the wood against the ground is good as new and essentially i view this deadwood assembly of a fin keel as a big wooden washer between the ballast keel and the hull.
any thoughts?

Jim Ledger
04-05-2010, 07:07 PM
Usually, the deadwood, the area aft of the ballast keel and ahead of the sternpost, is built from thicker chunks of wood than you describe. Although it's entirely possible to build from thinner stock, and there might be some advantages, there are some things to consider.

Each seam crossing the rabbet is a potential leak. The usual way to handle this situation is to fit stopwaters across the seam. Thinner pieces would need multiple stopwaters.

Be careful of timber that's been laying in the sun too long. If you have your timber sawn, it's possible to stack it properly, seal the ends, and keep it covered, to prevent the heavy checking you're seeing.

James McMullen
04-05-2010, 07:08 PM
Make sure you cut away all the sapwood.

Jim Ledger
04-05-2010, 07:36 PM
Huh — Deadwood and stopwaters ?

Is that a question?

kc8pql
04-05-2010, 08:39 PM
I am having a hard time fathoming why stopwaters would be used with a deadwood plan. I can't say that I have ever run into any deadwood configurations that would bisect the rabbet line and thus need a stopwater.
Humm. I've seen quite a few. The drawing below is the first example I find on the web at the moment, but it's fairly typical. Lots of places where the rabbet will cross a joint in the deadwood and will need a stopwater.

http://www.georgebuehler.com/georgeimages/Little%20Big%20Man/Little%20Big%20Man%20Construction.jpg

S B
04-05-2010, 09:53 PM
Jim,

First off I am sorry the way my response looks. Now that I see it, it looks sort of confrontational in bold quotes and it was not meant to be. I continually amaze myself with my inability to navigate these sites. However yes it was a question of sorts since I am having a hard time fathoming why stopwaters would be used with a deadwood plan. I can't say that I have ever run into any deadwood configurations that would bisect the rabbet line and thus need a stopwater. That's all I have to say
The only place needing stopwaters that i have come across is the deadwood. This is of course for boats not using FRP to seal the hull.

Rich VanValkenburg
04-05-2010, 10:13 PM
I'm assuming you aren't building with epoxy, you didn't say. If it's a traditional build, coat it liberally with boiled linseed oil and turpentine as you work. If you finish for the night but not quite finished with the shape, make sure it's well coated anyway and wrap it in plastic. You don't want it to dry out. When you're finished put two or three coats of red lead on each lift and use a good bedding compound as you assemble.

The idea is to keep the green wood damp so it doesn't shrink.

Stopwaters aren't always a great idea. Sometimes they work against you. Make sure you read up on them.

ssor
04-05-2010, 10:30 PM
White oak sapwood is no better than red oak sapwood. Slabs are usually mostly sapwood.

jcorlissf
04-06-2010, 05:04 PM
many thanks for all the response.
to qualify things i'll say that its not "traditional" construction so to speak. the hull is a strip-planked amphibi-con. i've removed the old keel assembly that was rotten to pieces, and the simplest thing to do seemed to be to cap the hole from below with a new plank keel instead of rebuilding the centerboard trunk etc. the previous owner elimated the centerboard trunk and so i'll keep to that model by filling in the space neetly with deadwood (there is still a moderate sized centerboard that is housed in the hollow of the external iron ballast). in the end there is no rabbet. the strip planks land directly on the beveled keel plank. the deadwood will just be hanging below the keel plank at this point. the two inch lifts i chose were a possible matter of simplicity. they seem as though they will be pretty easy to shape in the preliminary stage of things.

it sounds to me then that i might take that checked white oak, wet it good with boiled linseed oil and paint it with red led and proceed accordingly.

thanks again for the thoughts.