View Full Version : Reference marks
The plywood side planks on the Shellback Dinghy I'm building are supposed to line up with the aft face of the midship frame. There's no way this is going to happen. I have checked and rechecked my measurements, and all seems to be in order. Besides, the planks seem to fit great, albeit not lined up with the reference marks. What gives with this?
11-18-2000, 11:57 AM
I don't know if this will help, but I built the Pooduck skiff - the big brother of the shellback - and the first time I set up the midships frame, I got it on the wrong side of the line, with exactly the results you describe. I can only suggest the same rule I follow debugging software - question ALL your assumptions - the stubborn problems will be somewhere among the things you are SURE are correct.
11-18-2000, 01:28 PM
I had a similar problem building the Nutshell Pram. The bottom and the garboards went on fine. But the middle and sheer strakes just wouldn't fit. I was sure the planks weren't cut right. Luckily, before I started down that path, I remeasured everything, starting with the building jig. Guess what? I found that the transom cleat was about an two inches too low on the transom, giving the bottom too much rocker and throwing the entire hull out of alignment.
Ross is right. Go back to step one and recheck the things you are sure you got right.
07-24-2002, 09:22 AM
Sadly, I started down that wrong path - before figuring out what was wrong. The reference marks didn't line up on the middle planks (although they seemed to fit fine)and I went ahead with planking anyway. Now I'm afraid that I've planked half of my nutshell pram incorrectly. I'm even kind of afraid to finish it.
In retrospect, I think the problem might have been with the garboards - not trimming the planks enough where they met at the forekeel. As a result I ended up needing to cut away quite a bit of the plank at the bow to make it fit the knuckle at the bow transom. Same, then with the middle planks.
As a first time boat-builder and a novice woodworker, my question is "what do I do now?"
Is it salvagable? Will it float? is all the anxiety-laden experience I'm gaining worth the price of the kit? These are the questions that keep me up at night.
Recently someone tried to cheer me with this little ditty: "A little caulk, a little paint, makes a carpenter what he ain't."
I can only hope it's true for boatbuilders as well.
07-24-2002, 02:57 PM
Not sure what Dubb's problem is, but my advice for First Draft is - - Make symetrical mistakes, finish them nicely, and keep your mouth shut. Those of us who might notice would certainly not "throw the first stone". It's not likely to affect performance and no one is going to be measuring for a ratings rule. I learn from my mistakes - God, am I smart.
07-24-2002, 08:05 PM
first draft, By all means , finish it! make it fit as well as it can, make it look like a boat and it will be one, It will float and it won't sink even if you tried. Have fun and get at it.
Dubb, did you have any marks on your bottom ply?
if so did they line up with the midship frame. If they did then be sure you have your planks in the right orientation, that is pointing the right direction and on the proper side of the boat. Could have been a lofting problem way back when you cut them or even just the marks are in the wrong place. The fit is what counts but try and see if you can account for the marks being off just for your own piece of mind. If the bottom marks, assuming you have some , didn't line up then most likely the midship frame is on the wrong side of the station mark or the station mark was off. It will work out if you keep at it. It certainly happens to everyone.... ;)
07-24-2002, 08:11 PM
Paul and Gary have the right ideas. If you end up with a slightly different boat and it bothers you call it the "Nuts Hell" but enjoy.
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