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 J-3 Cub Construction Project Session #42

42 J-3 Cub Dummy Cylinders On Right Side of Fuselage

I received a suggestion from an FAC guy, Richard Adams, on how to mount the dummy cylinders, which I ended up using on the right side of the fuselage. His e-mail said:
 
Okay, now this is just an idea...what if you glued the cylinders on a piece of thin ply so you could have the cylinders as shown in the second picture, more realistic looking, but keep them together with the main fuselage. There still a danger of bumping the cylinder when attaching the nose block, but they would probably be stronger as a unit..............Rich
 
To begin with, I bonded the two right side dummy cylinders to a piece of 1/64" plywood as shown below. I was careful to also apply glue to the inside edges of the cylinder fins to bond them together as well making the two-cylinder unit very solid. 
 
This is a view from the back side of the right cylinder assembly showing the 1/64" plywood plate and the spruce strip inside the aft cylinder, which protrudes out an 1/8" in length for mounting. 
 
This shows the right side dummy cylinder assembly positioned on the fuselage, but not glued in.
 
This is another view of the right side dummy cylinder assembly on the fuselage.
 
This view from the top with the nose block in place shows how the right side cylinders are positioned slightly aft of the left side cylinders like the actual four-cylinder opposed Continental engine has. Notice the wedge shaped wafer on the base of each cylinder required to keep the dummy cylinders perpendicular to the center line of the fuselage. 
 
This shows the nose block partially pulled away from the fuselage taking the left front cylinder with it and the right front cylinder staying with the fuselage. None of the cylinders will be glued in until after the fuselage has been covered and the dummy cylinders have been painted.
 
This shows the nose block completely removed.
 
This shows all of the dummy cylinders with the nose block removed and positioned in the fore ground.
 
After Thoughts
I have done all I can with this @#$!! wide unscale front end using these dummy cylinders to try and capture the character of the J-3 Cub as shown below and still have a functional flying model, which
 
does require removal of the nose block. I know many of you probably think I have wasted my time since it doesn't look very scale anyway, but remember, I am trying to salvage this project as best I can.
 
On that note, it has occurred to me that I have another major problem to face when Mike Midkiff helps me test fly and trim this model. If you recall, I built in 4 degree down thrust and 2 degree right thrust when I drilled the thrust bearing hole in the nose block. This was Mike's recommendation, but only as a starting point. During the initial flight test, Mike may have to add or subtract to these values by shimming the sides and/or top and bottom of the nose block. Well, that is most certainly going screw up the dummy cylinder alignments! :O<  .............................Tandy 

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