fairing lapstrake plank edges on the boat

[ChuckG]

I'm embarassed to ask this question, but ....

I'm just putting the sheer planks on a 14 1/2 foot lapstrake rowing/sailing boat in the "whitehall tradition." As I stand back and look at the boat, I'm wondering if I dare attempt to fair the plank edges a bit more before I turn the boat over for framing and fitting out.

Any thoughts on how to tackle it? I'm thinking a stiff batten along the plank edge to give me a reference pencil line, and then going at it with a rabbet plane, set to take a REALlY light cut, with lots of standing back and chewing and spitting. Any other methods come to mind?

Or would I be better off waiting until the knees, frames, seat risers, gun'l etc are in and the boat is rolled over again for final sanding and painting? Some of the problem may go a way once there is a coat of primer on the hull, and one's eye is no longer following the grain of the wood, etc.

Any thoughts or remarks would be appreciated. Thanks

[Aramas]

Since I have all the hand-eye coordination of a blind amputee, I'd porobably be tacking a batten along the edge and running a router along it [img]smile.gif[/img]

[imported_Conrad]

Hi- a router can do a lot of damage in a hurry.

Since the unfairness is probably very small, I'd suggest some 80 ot 100 grit sandpaper on the edge of a bit of left over planking stock. Don't put it on the side that will lay against the hull! You can get 17" lengths of paper at most suppliers, or get a roll of 3" paper. I've used this technique to fair the edges of an old lap-strake Chris, and it went very quickly. The sanding batten only needs to be 18-24" long, and about 1/2" high to work well. You'll be surprised how little material needs to be removed to fair the edge. Good Luck!

[Thad]

Is this the lower edge or the sheer you are talking about? If the lower edge I wouldn't mess with it. If the upper edge or sheer, adjustment is usually lots easier before you have the internal structure installed, but it is also lots easier if you are working in a normal position instead of upside down on hands and knees. I would assure that the knees and ribs will not affect the shape much. I think the batten is the way to go, then cut to the line with a block plane with plenty of standing back and looking. Your impulse sounds good to me; it must be time to set her out of the stocks.

[ChuckG]

Thanks for the replies -

I'd not thought of using a router, and I've seen some folks do amazing work with a router. But for me, it's a bit too much of a whirling, screaming, torquing cloud of dust to be able to go slow enough.

A long sanding stick, made with a bit of planking stock and an old sanding belt might just do it. I like that idea; I want to give her a once-over with sand paper before I flip her over anyway.

Point taken about not needing to take much off. I don't want to get down into the lap at all, just take off a few high spots. And yes, I'm talking about the bottom edge (towards the keel) of the planks. The sheer itself looks pretty sweet. I think that's what makes me notice the other spots. (And I dunno how noticeable all this really is; I see it, and that's enough, I guess)

Do you think a coat of primer would exagerate the lumps, or disguise them? Should I get it all flat white before I try to make any adjustment?

Thanks again for the thoughts.

[Paul Scheuer]

A long stick with coarse paper glued to the working edge. If the grain pattern is misleading you, try different lighting so that the actual shape shows up in the shadows.

I'd suggest waiting until after you've asslembled the rails before you trim the tops. You want a fair curve and a pleasant angle on the assembly. You also want it to sweep into the angle of the quarter knees and breasthook.

[Don Maurer]

I used a rabbet plane to fair my strakes. It is much more precise than sandpaper and less chance of damage to the lower strake. It gives a nice clean edge, which the sandpaper won't. Sometimes just a bit of sawdust from the sandpaper is enough to throw off your perception of a fair curve.

[Jon Etheredge]

I used a rabbet plane to fair my strakes. It is much more precise than sandpaper and less chance of damage to the lower strake.

I think Don has given excellent advice. I would only add that you might want to turn the boat over and look at the edge right side up before you make any changes. The edge will look much different when right side up.

[Jack Heinlen]

You don't mention construction method. Glued lap will be more difficult to fool with.

A certain amount of playing with these lines is workable. A rebate plane, a small one, would be my preference. Unless you've got a really good eye(apparently not [img]smile.gif[/img] ) go gently, spring another batten.

But if you just got things screwed up, and we're talking too wide planks, just live with it, and build the next boat better.

It's hard to say witout looking at it. I wouldn't sweat it too much. Read Lapstrake Boatbuilding by Walt Simmons. He's got pics of a boat he built that had really ugly plank lies, one plank way too wide. It happens, move on.