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 "Cloudster" Construction Project Session #34

Speed 400  Cloudster Project
In order to lay out the wing's right inner panel, the dihedral and polyhedral inclination jigs had to be made. From Report No. 33 it was determined that the polyhedral break angle was 13.701 degrees. It is my custom to put half of this angle (13.701/2 = 6.85 degrees) on the end of the wing's inner panel and half on the end of the wing's tip panel. Since this angle is beyond 90 degrees, the angle of the inclination jig is 90+6.85 = 96.85 degrees. This angle was laid out on paper with a protractor as shown below.  
Then using a piece of 3/16" balsa, one edge of the polyhedral inclination jig was cut and sanded to the proper angle as shown below.
The 1/4" X 1/2" leading edge and the 1/8" X 1/2" trailing edge were pinned down on the right wing's inner panel. Then five of the R1 ribs were glued in place 90 degrees to the plan. The jig was used to set the inclination of the temporary polyhedral rib on the end of the inner panel as shown below.
Again from Report No. 33, it was determined that the dihedral break angle was 6.76 degrees. Since this angle is small, the total angle was applied to the root of the wing's inner panel. Using same piece of 3/16" balsa, the other edge of the inclination jig was cut and sanded to the proper angle (96.76 degrees) and used to set the inclination of the inner panel's root rib as shown below.
The main 3/32" X 1/4" top spar was placed in the rib cut outs without gluing. Heavy steel abutments were placed up against end of the spar to hold it in place spanwise. Then a small steel block square was used to check and adjust each R1 rib to 90 degrees on the main spar. Only the five R1 ribs were tacked in place with a drop of medium CA. Then the two inclined end ribs were checked with the inclination jig and tacked in place with a drop of medium CA.
The wing's inner panel was removed from the plan. It was placed upside down on the work table and the top spar was clamped in three places with Quick Clamps. This is a measure to insure that the inner panel remains straight while the bottom main spar is glued on. Only the five R1 ribs were tacked in place with a drop of medium CA.
The inner panel was placed back on the plan and the two end ribs were checked with the inclination jig before they were glued to the bottom spar as shown below.
After the rear bottom 3/32" X 3/16" spar and the three 1/16" X 3/32" turbulator spars were glued in place, all of the spars were trimmed off and the temporary polyhedral rib bar sanded smooth. Again, the inclination of the temporary polyhedral rib was checked using the jig as shown below. This was also done on the inner panel's root rib. Notice also that 1/16" gussets have been added to the outboard side of the rib/trailing edge joints to strengthen the joint. 
The picture below shows the wing's completed inner panel, except for the modification of the leading edge at the root. 
The picture below shows how the leading edge curves in at the root to mate with the center section. The wing will be built with a false straight leading edge until the center section's main spar carry through is completely assembled for accuracy purposes. Then this portion of the leading edge will be cut away and modified as per the plans below.
The wing's right tip panel will be built next. However, tomorrow is Christmas Eve and all modeling has to stop as Sue and I are having many guests and activities both tomorrow as well as Christmas day. so I will not get started on the right wing's tip panel until Saturday. So until then,....................
Sue and Tandy

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