Arcebus -- 2004 Progress 

Still unlaunched, but very close.  As our reverred president might say, "I     misunderestimated how much hard work it would be."

 

NACA Foil Design Spreadsheet

This past summer, we installed the cabin top and decks; built the lee boards and rudder; installed seats, mast partners, mast steps and outboard motor mount; cut the window openings; made a canvas cover for the cabin-top slot; sanded, painted, varnished, and oiled (and sanded and sanded and sanded).

Still to do:  Install the windows; finish putting reefpoints on the sail; install a boomkin for the mizzen sail (a spar that sticks out the back end to which the mizzen sheet is attached); finish rigging the sails; and attach the deck hardware.  Here are some pictures of what she looks like as of November 2004.

The motor mount, shown in the picture below, is a heavily-built box that slides up and down on two hefty aluminum channel irons that are attached to the transom.  The seats, shown in the interior shot, can fold up, providing enough floor space for a queen-sized air mattress.

     

We made the mast partner and mast step slots extra long to allow plenty of room for adustment in the rake of the mast.  I'm not certain how the rig will balance, so adjusting the angle of the mast is one way to compensate.  We also will be able to tilt the mast forward out over the water, where we can rig up a rope swing to use when anchored. 

We buillt NACA foil profiles into the rudder and lee boards by gluing on wood strips of graduated thicknesses.  After a little research on the web, I put together a spreadsheet for calculating and graphing the strip thicknesses and the bevels.  Anyone who is interested in using it (and has Excel) is welcome to download it.   (See top of page.)

The kick-up rudder is weighted with a 20 lb. chunk of scrap 1/2" aluminum that was routed and glued into the middle of the rudder.   For extra ballast, I added 50 lb of scrap 3/16" stainless steel sheet to each lee board.  This weight should be in an ideal position for ballast -- equivalent to an 80 lb. crew member hiking out.  As a little experiment, I left the lee boards flat on the outside, with the NACA foil only on the inside surface.  I'm hoping that this will promote some airplane wing-type lift to windward, although I've been advised that I probably won't be going fast enough to have much effect.  If nothing else, the wood strips and stainless steel (covered with fiberglass and epoxy) will add extra rigidity and strength to the lee boards.

Here is Aaron sewing the canvas top for the slot.  It snaps on and has PVC pipe arcs every few feet to hold it up.  Aaron checks one of the cabin top joints below.

      

 That's it for now -- it's going in for sure next spring.       
   

E-Mail me, if you like.