Wednesday, March 31, 2010

Boatbuilding 101

There are quite a few techniques to build a boat, but for my project I'm going to focus my sites on strip-planking.  Explained basically, the procedure for strip-planking consists of: 1) building a frame for the hull, 2) applying strips of wood to the frame, 3) using epoxy resin to seal and stabilize the wooden strip, and 4) fiber-glassing the inner and outer surfaces of the hull.  That's a very simplified explanation, but it gives you the general idea of the process.

The strips of wood can either be bought (expensive) or milled from planks of wood (and not just any planks, as the grain of the wood will effect everything from strength of the hull to warping).  At this point, I'm thinking I'll probably opt to mill my own strips because the cost of pre-milled strips is about 3x as expensive as buying the equivalent amount of lumber.

Epoxy and fiberglass serves to hold the strips together as well as add a significant amount of strength.  Another obvious advantage is that, when done correctly, this process seals the wood from humidity which eliminates many problems inherent in wooden boats.  The cost of the epoxy, by the way, is the most expensive material cost in building a strip-planked boat.

One aspect of boat building that I had not thought much of is that boat building requires a significant amount of lofting.  The lofting charts are a bit more daunting than I expected.  Lofting is basically taking several tables of offsets and converting them into the physical, full-sized form that you construct the frame of the boat from.  Although I could just buy a boat plan that has all the offsets lofted, and Gorman recommends this, I really would like to try my hand at lofting...  The verdict isn't out on this decision yet.

The University of Texas actually has a sailing club that goes on sails every Saturday, and I plan on attending this weekend!  Hopefully there will be a post or two on sailing technique soon...

Take care everyone, and here's the Term of the Day.

Term of the Day: Points of Sail
A boat's point of sail is the direction the sailboat is traveling in relationship to the wind.  First, there is the distinction between a port and starboard tack.  If the wind is coming from the starboard (right) side of the boat, the boat is said to be on a starboard tack.  The reverse is true for a port tack.

From there things get a bit more technical.  Modern sailboats can generally travel up to about 45 degrees into the wind.  If the boat is pointed anywhere within about 45 degrees of the direction of the wind, the boat is said to be in irons, and won't go anywhere.  When a boat is traveling as close to the wind without being in irons, the boat is close hauled.  When traveling at 90 degrees to the wind, the boat is on a beam reach.  Slightly into the wind is a close reach (or fetching), and slightly with the wind is a broad reach.  When the boat is close to moving in the same direction as the wind, the boat is running or running downwind.
  


 




 

2 comments:

  1. Sounds like we have the beginnings of a working plan here. I'll go read what you sent me. By the way, do you actually know HOW to properly mill the strips and/or do the lofting? I realize the money issue, but if you waste three times the wood (and time) trying to figure out how to mill it correctly, you might find yourself in a bit deeper hole. Again, though, you tell me what to do, and I'll do it.

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  2. Lol, Yeah I do... in theory ;-) Gorman has all the necessary tools in his shop. Love ya Bro!

    P.S. Follow my blog already, geez!

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