Deck alignment on the Chesapeake Double

I'm building a Chesapeake Double from plans, and I'm mounting the deck beams. It looks like the top of the deck forms a straight line from the bow to the stern. Is that right? I want to make sure all the beams line up properly and there aren't any gaps between the deck and the beams and tops of the bulkheads.

 

Gary


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RE: Deck alignment on the Chesapeake Double

Typically on the Chesapeake the deck foward of the cockpit is a different radius than the deck behind the cockpit.   Make sure the radius of the beam and station location (distance from bow "datum") are correct. Make sure the hull width at the shear clamps is correct at beam attachment.   I suspect the elevation of the bulkhead behind the aft cockpit is lower than the deck beams.  Looking at the side view pictures in the Chesapeake Double listing on the CLC web site it seems to confirm that.   

RE: Deck alignment on the Chesapeake Double

It's a 24" radius from stem to stern. Most of the Chesapeakes have a smaller radius (greater camber) forward than aft. It's constant on the Double and Triple.

I'm probably just overthinking this. I can adjust the heights of the bulkheads with a block plane and my 24" radius template to make every line up for a good fit.

RE: Deck alignment on the Chesapeake Double

   The 17's are drawn with a straight line profile from bow to cockpit, and that's not at all what the actual profile is.

I'm guessing the double, also a pre-software design, simply has the deck profile 'conceptually' drawn.

I think you may get yourself into trouble if you try for an arbitrarily straight centerline profile. Up front, the deck has to have an inflection to deal with the up-sweep of the sheer. The cockpits break the deck into three independent chunks, so the aft two could be manipulated as you describe, maybe.

RE: Deck alignment on the Chesapeake Double

   "Up front, the deck has to have an inflection to deal with the up-sweep of the sheer."

Not necessarily. The sheer may have been developed as the intersection of the hull and the deck cylinder. We plane the sheer clamp to maintain the constant 24" radius, creating a constantly changing angle. And, since we're dealing with plywood, the deck has to be either flat or some kind of cone or cylinder. It really won't torture much over that great an area. I suspect that's why the change in raduis on the smaller Chessies occurs at the cockpit in order to make the tortured area small (between the coaming and the sheer clamp).

With the deck forming a cylinder, the tops of all the bulkheads and beams have to line up. The only question is if axis of the cylinder they form is horizontal or slanted downward toward the bow. There could be a slight torture there, but not very much.

Thanks for all the input. Just writing it out has helped me think this through. I'll post the result when I get the deck on.

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