bobby burington wrote: > I have discovered a small problem with one of the wings on this plane > project I have sort of inherited , the rear spar is about 3/16 shy of what > is called for in the plans and the airfoil is slightly misshapen because > of this.
If you are saying that the spar is not tall enough, you need to use T-88 or some other suitable epoxy to glue some more wood on top of the spars, rather than use foam to make up the difference to get to the airfoil profile. The skin's connection to the rest of the plane is done through the spar cap, and foam cannot support the load (it is structurally "useless"). This is really easy if you have some easy slivers that were created during the spar making process, but since it looks like you acquired this as a project rather than making it yourself, you probably don't have those. I would order a piece of spruce the right thickness and maybe an inch thick and long enough to make your tapered piece from Wicks or AS&S. It probably won't cost $10. Then use a table saw and a a simple fixture like the one we use to taper the spars to slice off some strips that look like what you need, maybe even a 64th taller, so you can sand it to the right taper after it's epoxied in place. The jig I'm referring to is shown about half way down http://home.hiwaay.net/~langford/kspars.html . This can also be done on a bandsaw, of if you're imaginative enough, with a circular saw (just glue the strip to some "cheap" wood on edge and use a straightedge... Mark Langford, Harvest, Alabama email: N56ML "at" hiwaay.net see homebuilt airplane N56ML at website: www.N56ML.com
