Monday, November 1, 2010

Reverse Engineering



This weekend offered little in the way of time to get out to the boats. Nevertheless, Friday afternoon and Saturday morning we put some sweat into the stem on No. 2, but kept running the gamut of finding which fasteners were holding it after we removed all we found. It was an interesting game of hide-and-seek, but it brought to light some very interesting information about how the boats were actually built. And so because its Monday, day of big dreams and little productivity, with even lower enthusiasm, let's review what we at the Dockyard have learned about the process.

First, we know - or we think we know - what the boats cost. According to the contract taken out at the Norfolk Navy Yard on March 3, 1904 a total sum of $14.72 was to be paid for each Monomoy-type Whale Boat completed and altered for Arctic service. Yes, fourteen dollars and seventy-two cents. I'm still working on nailing down the relative value of the dollar at the time, but I'm willing to bet that even with adjusted dollars we couldn't build them that cheap. They were cranking these things out. And not just Monomoys, boats in general. So whatever means they had of putting these together, I'm guessing that there was no time for any unnecessary work. Less art and more haste, sort of thing.

The clues we've been gathering from the boat give us a good idea of the order in which they were assembled. This is particularly true of the stems, where we're finding that this is not necessarily an obvious thing. But based on the general lack of data, I've widened my investigation to examine other reference material pertaining to Navy boat construction over the years. Here's how I think they did it, so far:
  1. Shape the keel, lay out on blocks.
  2. Shape stem and sternpost, bolt into place on keel. Brace entire structure as necessary to keep upright.
  3. Assemble molds, each molded to the inside of the planking. These are fitted directly to the keel.
  4. Run ribbands from the rabbet on the stem to the rabbet on the sternpost. Do not notch into the molds. Use mechanical fasteners to connect to molds.
  5. Steam-bend frames into position, laying them inside the ribbands. Clamp to ribbands and screw into top of keel.
  6. Begin planking at the sheer. Work one plank per side at a time, and duplicate on opposite. Lay the whole assembly on side as needed (see photo of motor whaleboats, 1953).
  7. Once several strakes are run down from the sheer, begin work on the garboards and work up.
  8. When planked, attach temporary beams gunwale to gunwale, remove molds.
  9. Insert keelsens, CB trunk, clamps and thwarts.
  10. Insert deckbeams, decking, bow and stern platforms.

Note the complete lack of such things as a strongback, heavy framing etc. Either they were just $hit hot or we've been approaching wooden boatbuilding with a vast degree of overkill. I mean, the molds and strongback for the 25' Launch weigh as much as the finished boat itself. In contrast, those light frames look quite dainty. Not to mention the rolling about of the structure during construction - seems to make building them upright (more or less) a lot less stressful, AND it removes the operation of having to flip them over. Hmmmm.

BT

TONIGHT we will assemble the Dockyard crew to help the operational side in recruiting. Monomoy No. 1 is ready for duty, and we're going to go park her in front of the NEX, lay out the oars, step the mast and hoist sail (wind permitting) and some flags, and get attention! All hands meet at the Dockyard at 1600 and we'll begin making preps to go.

NNNN

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