|Photo by D. Reifsnider|
In this, the fourth part of our series on building the Senior Telemaster, I'm going to go over construction of the wings struts. While the original plans don't call for them, I decided to add them as a safety measure since I was using an experimental wing mounting system. Also, I think they look cool. The strut mounting required that I fabricate a bracket for attaching the strut at both the wing and fuselage. Below you will see the bracket that was made for the wing.
The wooden hardwood block was glued in between the upper and lower spars at so that the bracket hung down at the 9th outboard rib. Unfortunately I failed to get a photo of it prior to covering, but below is an illustrated drawing of it's placement.
The photo below shows the finished bracket exiting the covering. Using 1/4" square balsa, I boxed in around the bracket so the covering would have an edge to adhere to. After the wing was covered, I put a bead of epoxyy around the bracket to create a fuel proof seal.
Now for the strut attachment on the fuselage. Starting with 5/8"x 3/16' stock and a Dremel Tool, I fabricated an aluminum bracket that spans the entire width of the fuselage and is fashioned so that the aluminum strut tubes slide over each end. The bracket is fastened to the bottom of the fuselage with a couple of socket head screws that go into blind nuts installed in the plywood fuselage support aft of the landing gear plate. The strut tube is fastened to the bracket with a cotter pin.
|Strut bracket attachment to bottom of fuselage|
As for the struts themselves, I used 5/8" K&S aluminum streamline tubing. In order to give them some added strength, I ran a piece of 3/16"x3/8" balsa inside the length of the tube. I then fabricated an end piece for attaching the tube to the bracket at the wing. The piece was fabricated from brass bar stock and 4-40 threaded rod that was bent into an "L" shape and soldered to the bar stock. A ball link was then attached to the threaded rod.
The above piece was then secured into the end of the strut tubing using J-B Weld liquid steel epoxy resin.
The finished struts are then attached to the wing with a bolt through the ball link and with a cotter key though a hole drilled the tube at the other end.