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Audasea
01-28-2007, 12:34 PM
I originally planned to use some clear red oak I had for transom knees and breast hook on a dinghy I'm building, but have changed my mind due to concerns over potential for rot.

On hand, I have some nice cherry and yellow pine (stair tread). Other stuff I can get my hands on easily are walnut, white oak (worry about gluing that in with epoxy), ash and Doug fir. Plans call for 3/4 inch stock, but I might use full 5/4 stuff (7/8 to 1 inch) as most of the wood I have is rough sawn to a full inch and needs to be surfaced planed down to size. It cleans up pretty well at 7/8 inch. The DF is 1 1/2 inch stock.

These will be finished clear. If those choices are no good, what would be the ideal wood to use?

Bob Cleek
01-28-2007, 12:59 PM
Go with the oak, white preferably. You should use fasteners in addition to your epoxy for an application like a breast hook or knees. Since it is a dinghy, these will be very well exposed to the air and rot should not be any concern. Rot needs moisture, air and a friendly temperature. If the wood is well ventillated, you won't have moisture, and so you won't have rot.

ishmael
01-28-2007, 04:41 PM
I like a hardwood in these pieces, and as Bob said rot isn't an issue. Walnut or mahogany of the woods you listed. The oak would work too, if you didn't want so much contrast. A traditional way is apple knees, but you don't need such. Crotch wood is moredifficult to get right.

Tom Hill's book on ultralight boat building has the most straighforward explanation of making and fitting these out of straight wood I've read. They're a pleasant project, with quite a bit of shape. They can be made as simple as you want, but I like them shaped. Little touches really dress a boat. Not at all difficult; nice exercise.

David G
01-29-2007, 12:17 AM
None of those is the ideal wood... cause there ain't any such critter. They all have their strengths & weaknesses. But I'm just being pedantic. Any of the woods you mentioned would do fine. You're wise to skip the red oak, though. Since you have the cherry on hand, I'd go with that. It's strong enough, finishes up real pretty, and isn't particularly prone to rot, in case of moisture intrusion. Of all you listed, the one I might stay away from is the ash. And that's just a mild preference. It's been used on boats for a long time, and I love the look, but it can get some mold in the open pores if it's not dry enough when finished, or if your varnish isn't well-maintained or high quality (and even sometimes when it is). In order to recommend beyond general suitability, we'd need more details. I'm curious anyway. What are you building?

Audasea
01-29-2007, 07:39 AM
A Spindrift.

One wood I would consider to be almost ideal is Black Locust, but finding that in nice clear pieces is hard to do. By the time that stuff gets big enough to make a nice piece of wood, disease sets in and rots out the middle.

ssor
01-29-2007, 06:17 PM
I was reading about the Nevis Island lighters the other day. Whenthey would decide to build one they supplied some wood cutters with templates of the shapes they needed and the wood cutters would find grown pieces that would allow the shapes to be cut out.

ishmael
01-29-2007, 07:21 PM
Cherry. I missed that on your list. It's good stuff for this, though likely a little harder to work than all but the oak.

I put grown apple knees in the first skiff I built. Working with them is kinda fun, but they tend toward moving around quite a bit as the moisture changes, and you don't really need them. Straight grain, forty five to the centerline for the quarter knees. For the breasthook three pieces. The two sides running grain parallel to the sides and a narrow filler between. Hill's book is good walking you through it. Sharpen up your spokeshave. I think giving them some shape is really important in a small boat. That, and lightening the ends of your rails, makes all the difference in appearance.

Best of luck, and how 'bout some pics?