Tolerably out of whack?

[DavidF]

Some background: I am not patient with numbers. I am a sculptor by avocation.

So I've got my Hylan Chesapeake skiff off the molds and over and I am getting the CB trunk ready for her home. In most places center is directly between the sheer lines. But in some places it is off by as much as an inch. This is true of the chines as well. I think I know where I screwed up (molds) but I think I am committed. I have used a hell of a lot of epoxy. So my question is really about imagining the future and maybe seeking some advice on mitigating the situation.

Is my boat going to sail in circles? Or will that level of out-of-whackness tolerable?

I'll probably try to pry the gunnels before I attach them and the knees. Anything else I might do?

Thank you in abundance,
David

[ 10-11-2005, 07:37 PM: Message edited by: DavidF ]

[Bob Cleek]

Not exactly sure what you are describing, since the "sheer lines" are on parallel planes with the "center" as I understand it. The "margin of error" in any event is going to be proportional to the size of the boat. Are you saying your molds weren't properly centered? If so, it's a minor miracle you got her planked at all. A picture would be worth a thousand words here. Let's just say that any measurement error in lofting and layout will continue to compound as the boat is built. Sounds like you are past the point of no return, though. How much epoxy have you got?

[ 10-11-2005, 08:58 PM: Message edited by: Bob Cleek ]

[bugeye]

Hi,
I wouldn't freak out too much, it's rare that a boat comes out absolutely perfect to its lines. My boat is a lot bigger than yours, but when I replaced the deck, I discovered that up forward, she's an 1 1/2" wider on one side, and back aft she's an inch wider on the other. Once you're out sailing the boat, you'll never think about it again. Remember, you're not building a space shuttle, which is good, because they blow up alot. I'm sure Doug Hylan did his homework when he designed this boat, but the boats on which it's based were built by "rack of eye". You can be sure they were crooked, and can be sure their owners didn't care. Have fun.

[Bob Smalser]

I don't believe I've ever worked on a boat that when I put the tape and string lines to it, it wasn't out by something. Bending wood over molds and then expecting cabinetmaker tolerances on the resulting structure just isn't realistic.

That said, and inch could be nothing, or it could be a lot, depending on where it is. Mostly it depends on if you can see it. I wouldn't install a centerboard trunk without every knee installed except those supporting the trunk, and I wouldn't install either without the boat properly supported so it is true. The centerline for the CB trunk is keel center at transom to stem center via string line...I wouldn't worry about the chines because you can't do anything about them.

You can make some adjustments before the knees are in, depending on the problem. I just successfully took the considerable twist out of this little pram by removing the knees, torquing the boat true, and installing a more elaborate set of laminated knees sprung hard in place.

http://pic3.picturetrail.com/VOL12/1104763/8408305/113944400.jpg

[ 10-11-2005, 09:27 PM: Message edited by: Bob Smalser ]