G.H. Coates, LLC

Ideas That Work

[Under Construction]










I've been working on a 1920's style launch for a few years.  I don't like working in wood, and rust and corrosion are such a bore, I decided on building in Cupra-Nickel sheet.  OK.  All I needed were plans.  Well, I didn't find any I could afford, and most were/are supposed to be build in wood.  Now I could have taken plywood plans and built from them, but there's this new thing called a computer and it is SO versatile.  I live a fairly sheltered life, but I have yet to see a CNC bandsaw, or skillsaw, or jigsaw for that matter.  I guess that may be a market niche for someone.  But there are CNC plasma cutters.  Now we're talking fun!!!  I figured I might as well start out with something that was easily transferable to a CNC machine, so I started with a free download of a hull design software, and after about 3 months of tinkering,  I came up with a hull that looked nice.  Then I printed it out on paper, cut it out with scissors, taped it together, and floated it in the sink.  Yup.  Just like that.

Great!!!  Now a little bigger, and in steel to test the whole flat sheet CNC idea.  No problem.  Took less time than it takes glue to dry.


Now I designed some stations, or bulkheads, or ribs and went for a size that I could do some weight and float characteristics with.

 This is the beginning of the 8 foot launch.  This is 16 gauge steel.  It's a little heavy for this length, but made for a very strong hull.  Some of the plates can be seen on the floor in the background.  Since the hull shape is developed from flat plates, the skin is stressed, or becomes a structure of it's own.

  The 8 footer floats!!!  Not too bad.  The tape covers some leaky seams.  The full size launch will be 22 feet LOA, 6 feet beam, and draw 12 inches loaded to 1500 lbs.  The 8 footer I stood in to get some idea about the loading.  It does very well with the 190 lbs of me in it.

    Some folks might ask why I went to all the trouble to build three "models" of a launch design.  Well, I figure that with some of  the money I saved by not going to Marine Architect School it would be a good idea to see if this whole thing would work before I spend an incredible amount of money building 22 feet of yard ornament.  Especially in CuNi. 


  In the next few weeks, I will begin a 16 footer.  I'll post more on the progress as it comes.