View Full Version : Keel/backbone timbers: how green?
08-08-2001, 12:38 PM
Check my thinking on this:
Keel timbers ought to be green, so when the boat hits the water they won't swell up and cause trouble.
But how green? Can I go cut down a white oak, shape it, and start building? There's a local mill that sells wood 'about as green as it gets.' Or is it safer to let it dry at least a little bit...and how much is 'a little bit'?
And the rest of the backbone -- deadwood and stem timbers. How green should (can) they be? Again, the greenest wood is the cheapest, and if it's what I should be using anyway, there's no question.
By the way, I'm building in an unheated, un-air conditioned shed with a dirt floor in Virgina. Lots of humidity this time of year.
Any advice or thoughts?
Seth, what are you building, how big is it? How long will it take, realistically, before your boat is ready to hit the water?
08-09-2001, 02:34 PM
I'm building a 30-foot hard-chined planked sailboat. Realistically, it could be 3-4 years before she hits the water.
I've had some green (white) oak 6x8s in the shed since early spring, with latex slurped on the ends, and minimal checking so far.
I've considered getting or borrowing a moisture meter...but I'm not sure what the ideal moisture content is for these keel and deadwood timbers.
08-09-2001, 05:58 PM
Your thinking is good, but you need the opinion of someone who has successfully delt with this IN YOUR LOCAL. A lot of things have to be done different down South than they are up North, and your sittin' in the middle. We can speculate and generalize and tell you to redlead or soak with anti-freeze, but surely you are not the first person to undertake building in your area. Track 'em down and ask a pro.
Seth, Get yourself a good moisture meter, preferably the probe type and put it to use. It's one of the most valuable tools you will own if you are building a boat. Try to start with material that is probably 15% to 18% moisture content. It will be relatively stable to work with. Between 18% and 20% you'll see alot of your hard earned structural joints open up and your pieces move as the keel, deadwood, gripe, stem, stern post, horn timber and transom frame dry and try to reach some point of equalibrium. Above 20% and the material is unsuitable for putting into a boat. It's better to start fairly dry rather than green, especially if it will be approx. 3 to 4 years before you hit the water. If you are not adverse to buying some really fine Doug Fir for your keel and deadwood out of the Seattle area and having it shipped, call Peter Wagner at 360-674-2700, see what he's got and what it might take to ship it to you. He has cut and supplied old growth Doug Fir for many boat projects including the USS CONSTITUTION. It might be an acceptable way for you to go. Good luck.
[This message has been edited by RGM (edited 08-10-2001).]
08-10-2001, 09:21 AM
There is little advice I can give you on this, but here's one bit. If you're buying from the sawyer and can wait, get winter-cut wood. That way the sap is out of the tree, and nature's done a lot of the work for you. It also lessens movement later on, including checking. Somewhere in my brain is a tidbit that says that it also improves rot resistance, but I can't back that up with a source.
If your 6X8s were winter cut, which seems likely, then you're probably good to go with them. If you need more, I'd wait for timber felled in November or later.
Just my $.01
08-10-2001, 09:54 AM
Thanks for the advice. I had a feeling a moisture meter might be the best way to be sure. Any advice on that? I hear Wagner makes good ones; and Woodcraft carries several as well as a few from other mfrs.
Building in the mountains of Virginia, there are few local boatbuilders (lots of trees, though). But I'll make some calls to the Sultana folks in Chestertown and a lumber supplier down on the Rappahannock.
Seems like the consensus is: since it'll be so long before the boat hits the water anyway, starting with green wood and keeping it wet is a bad idea? Starting with drier wood is the answer? Once the boat's in the water, any thoughts on what the "final" moisture content of the timbers will be, once they've stabilized?
Seth, a couple thoughts, don't limit yourself to lumber suppliers that are local to you. Anyone that's worth buying boat lumber from has been in the game a long time and they already have the shipping details/network figured out. You might be suprised at how easy it is to get some wood delivered to your door or close to it (sawyer that's close by) from the Northwest. Or call Brad Ives (Deep Water Ventures) at 508-725-7255, or fax inquiries to him at 508-696-5296. Brad is located around Martha's Vineyard I believe. Tom's input regarding winter cutting vs. summer cutting is thoughtful. However, our beloved government, particularly the Navy, has done some extensive testing that proves that there is little or no difference in the amount of sap between winter cut and summer cut trees. Problems arise when the trees are left lying around on the ground and/or baking in the summer sun prior to milling. Don't be too concerned about what the moisture content will be after the boat hits the water, mother nature will take care of that. You take care of the rest. Have you collected the usual assortment of boatbuilding reading materials and reference books? Do that if you haven't already. Do you have an e-mail address available to you?
[This message has been edited by RGM (edited 08-10-2001).]
08-13-2001, 11:09 AM
Yes, I'm slowly accumulating a reference library of books and people I can use as resources....My e-mail is srwood73atremovethistexthotmail.com. (Maybe that'll keep the auto-spamming down.)
I guess what's confusing me is that I'd always thought/learned/heard that starting out with green timbers is ideal, if you can keep them wet. Starting with dry timbers seems like taking a risk of excessive swelling once they take up water. At any rate, I'll start making some calls.
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