Kaimusailing

The next step in the ama build is to bond the ends of the hull together at the ends. The sheer stringers were purposely left quite a bit long. They can be used during the glue up to pull the hull sides together at the end and relieve some of the pressure on the tape at the keel. When the end of the hull is completed, the sheer stringers have to be relieved on the inboard side at a shallow angle so that the two ends of the stringers can mate. This cut is lined up with a centerline string on each stringer separately by bending the stringer and hull side into position and marking. The two stringers are then cut with the multitool using the halfmoon blade. This tool can be used like a Japanese pull saw to make very accurate cuts. The stringers are cut almost to the mark, then both stringers are brought together on the centerline and trimmed using a sander to an exact fit. The lineup of the hull sides at the bow can induce twist in the hull and is also the last chance to correct twist that has occurred in the midships sections.
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I had posted the offsets for the ama in decimal feet when I made the design last winter. Here are the offsets with additional decimal inch conversion:
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#1 and #3 Bulkhead Offsets at 2' from end (8' between 1 and 3)
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Y=outboard from centerline Z=up from baseline (keel at midships)
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Deck
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Y dec. ft. Z dec.ft. Y dec.in. Z dec.in
.24910----------1.08726-------2.9892----------13.04712
.23465----------1---------------2.8158---------- 12
.19576----------.87925---------2.34912--------10.551
.15291----------.73222 ---------1.83492--------8.78664
.10274----------.58614---------1.23288--------7.03368
.04268----------.43923 ---------0.51216--------5.27076
Centerline------.34118---------C/L-------------4.09416
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#2 Bulkhead Offsets at 6' from ends (amidships)
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Deck
.4955-----------.9847----------5.946----------11.8164
.4601-----------.8795----------5.5212---------10.554
.4212-----------.7761----------5.0544----------9.3132
.40226----------.73239--------4.82712--------8.78868
.33642----------.59394--------4.03704--------7.12728
.33061----------.58571--------3.96732--------7.02852
.2527------------.4391---------3.0324----------5.2692
.1695------------.2923---------2.034------------3.5076
.0857------------.1462---------1.0284----------1.7544
Centerline-------0--------------C/L-------------0
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The use of decimal inches works well with the 6” digital caliper I'm using. It is a cheap device from Harbor Freight, but decimal inches can be quickly set on it. Working with a 6” grid enables that all the offsets can be plotted accurately. The offsets are taken right off the Delftship 2D screen and are as accurate as the software is. Making a model confirms a hull can be made without any huge whoop-de-do's.
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Hull Panel Offsets, grid 3", gunwale is baseline, bow is 0, midships is 72 inches
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station----------keel edge above gunwale
0-----------------0
1.9"-------------3”
3----------------4.7
5.6--------------6
6----------------6.2
9----------------7.1
12--------------7.8?
15---------------8.4
18---------------9
21---------------9.5
24---------------9.9
27---------------10.4
30---------------10.7
33---------------11.1
36---------------11.4
39---------------11.7
42---------------11.9
45---------------12.1
48---------------12.3
51---------------12.5
54---------------12.7
57---------------12.8
60---------------12.9
63---------------13
66---------------13
69---------------13.1
72---------------13.1---(Amidships)
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The picture is of the ama after gluing in the bulkheads.