rossmick

Well, I would like to say the ailerons shown in the prior thread were prototypes but the simple truth is they are just wrong. Wrong width, wrong length on the trim tab. "D" section was too thin and when slot was cut for the hinge the section became weak. New "D" section has an added 1/8" layer behind hinge pin section followed by the 1/4" beam on the center web. Aileron corrected for width with the curve to the tip not cut in at this time. Trim tab is .75" by 5.5" and tapered roughly following the LE.. The hinge pin concept is that it would be removable and this causes a change in the servo linkage position which is now on the inboard end of the aileron.


Servo bracket is made from a 1 x 1 alum angle with 4-40 taped holes for attaching the servo and 5/32" holes for mounting the bracket. The 3/8" 4-40 Allen head bolts for mounting the servo are hard to fine and now have a bunch ordered. I have chosen the dual arm as recommend by Sam with the included 4-40 ball link. I have tried the black & yellow Nyrod system that I have seen and for me it showed some slop and I was afraid that the ailerons would flutter. I then used the same system as I did in the Corsair using brass square tubing. I use a 1/8" round tube that is inserted in to the ball link after drilling out the 4-40 tread by using a 1/8" drill bit. The fit is so snug that the tube has to be taped in. The round tube in then slid inside, with a snug fit, the K&S #152 5/32" square tube where a 1/16" hole is drilled through and a small screw is screwed through to hold the round tube from pulling out. I cut the round tube just short of the length of the square tube for the reason that it makes the linkage very strong over its entire length. Then this assembly is inserted in the K&S #153 3/16" square tube which is glued and trapped between plywood on the aileron. Here the #153 tube is cut so that the hinge pin can be pulled once the servo is removed allowing for the aileron to be removed for repair or replacement. Note, the ailerons are fabric covered and not balsa as per plan.


Mounting the servo in the wing is done so that the centered arm is at the center position of the rib and then the #153 tube is positioned in the slot in the aileron. The aileron is then aligned with, and held, on the bottom line of the rib, Now Hysol is applied around the #153. After the glue is dried, the plywood trap pieces are glued and screwed in place (be careful not to pinch the #153). Be certain that you have 3/4" up travel and 1/2" down travel. This is accomplished by the position of the servo from the hinge. The aileron is 3 1/4" at the inboard tip so at 3 1/4" forward of the hinge you would need 3/4" travel down inside the wing. As you rarely have that much room you would need to move the servo closer to the hinge line so that with less servo travel you will get the 3/4" at the tip. This is a tight fit in the wing here and the hinge block had to be trimmed back to get the servo in the correct position. The ball link is also critical because with the square tubes you would never get the alignment correct without binding.