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j ferguson · 23 December 2007, 05:22 AM

Joe,
a clue that embedding the vertical strut midst the ribs might be wrong is that the ends of the upper horizontal "gusset" aren't doing anything - not load carrying except as transferred through glue shear connections. True, glue is very strong in shear, but what you have shown is a segmented beam. If you move it out of the plane of the ribs, it doesn't need to be interrupted.

beautiful drawing by the way.

You might assume that with all the glue you're going to use, you will get good shear connections in that interrupted horizontal "plate", but it would be a whole lot more sure if it was adjacent to the ribs. also it would be a whole lot easier to build.

another clue might be the width of the top and bottom longerons. they should be wide enough to accommoate both ribs and vertical struts if what I'm suggesting makes any sense at all.

We used to have a real wood wizard here who was building a Spad. In my ignorance, I would think it a good idea to build, when in doubt, so you don't absolutely depend on glue as structure, but more as a method to retain structural elements in place.

best, john

23 December 2007, 05:22 AM	#25 (permalink)
j ferguson Forum Ace Join Date: May 2006 Location: Intracoastal Waterway, USA Posts: 581	Joe, a clue that embedding the vertical strut midst the ribs might be wrong is that the ends of the upper horizontal "gusset" aren't doing anything - not load carrying except as transferred through glue shear connections. True, glue is very strong in shear, but what you have shown is a segmented beam. If you move it out of the plane of the ribs, it doesn't need to be interrupted. beautiful drawing by the way. You might assume that with all the glue you're going to use, you will get good shear connections in that interrupted horizontal "plate", but it would be a whole lot more sure if it was adjacent to the ribs. also it would be a whole lot easier to build. another clue might be the width of the top and bottom longerons. they should be wide enough to accommoate both ribs and vertical struts if what I'm suggesting makes any sense at all. We used to have a real wood wizard here who was building a Spad. In my ignorance, I would think it a good idea to build, when in doubt, so you don't absolutely depend on glue as structure, but more as a method to retain structural elements in place. best, john Last edited by j ferguson; 23 December 2007 at 05:51 AM.