LAST EDITED ON Oct-10-03 AT 08:47 PM (CDT) I'd like to address these apparent problems in the kit. In fact, I already did some time ago, but it was on the old RC Online product review forum, and unless someone managed to make a save on that post, I'm afraid it's lost.
Soo, let me try again, and I'll try to keep it brief.
There were indeed some changes made while the prototype was being built. That's why some things are a little misleading between the plans and the instruction book.
One item to make note of, the book outlines a wing building method which uses the "leveling bar" form of jigging. John didn't understand the method used to construct the PathFinder wing, as it was different from what he was used to.
The wing has ribs that are flat from the high point aft, and it is designed to be built on a flat level surface. One method would be to cover the plans with either waxed paper, or the clear plasic sheet from the backside of some MonoKote.
It may be of help to very lightly spray some 3M contact adhesive in the area of the center sheeting, and the trailinng edge sheeting. Spray this directly on the waxed paper.
You should have spliced the trailing edge sheeting together with a skarf joint.
Place the spliced, and trued, trailing edge sheeting, directly to the covered plans. The light coating of 3M will hold it in place for you. Use some scrap 1/16" balsa and place it in the center section, where the center sheeting will be installed later.
Preshape, using the rod method, the 1/4" X 3/8" balsa internal trailing edge.
Align and glue the shaped internal trailing edge in place.
Using a slotted piece of scrap balsa, (the slot should be the same width as the rib material, and at 90 degrees to the straight edge.), Align and place the center ribs, and each tip rib. Pay attention, the center ribs are not the same as the tip ribs, even though the wing is a constant chord wing. I use a Ca applicator to make sure that I don't overdo the amount of glue used. Glue the rear of the ribs to the trailing edge assy.
Using a skarf joint, make up the full legnth top and bottom spars.
Set the top spar, after you have spliced it, into the spar notches in each of the tip ribs, and the center ribs. Don't glue the spar in yet.
With a little twist and slide, using the alignment jig, as before, set the rest of the ribs into place. Note, You did laminate and prepare the 6 ribs the gear block attaches to, didn't you? Make sure these 6 ribs are placed with the notch down, as you are building the wing right side up.
Once the ribs are all placed, use the Ca applicator and glue the ribs to the spar and trailing edge assy.
Prepare the full legnth leading edge, using a skarf joint.
Install the leading edge starting at the tip ribs, and center ribs. Be carefull to maintain alignment. Once this is done, glue the rest of the ribs to the leading edge.
Align and place the top trailing edge sheeting, and glue.
It's now time to turn the wing over so you can install the bottom spar, gear blocks, and bottom leading edge sheeting.
Installing these should be relativly easy if you've even built only a few planes in the past.
A word of note, The gear blocks provided with the some of the kits, has two, too small blocks to use for the vertical leg of the torsion gear. I replaced these blocks with correctly sized pieces cut from a single additional gear block.
<<<<EDIT>>>>>
Sorry, I did this from memory, and realized later, that the supplied gear blocks are too short also. One set of gear blocks, from Sig or Brodak, will provide enough material to construct proper gear mounts, including the longer torsion blocks. Sorry for the oversight.
<<<<END EDIT>>>>
Be sure to install the tip weight box from the bottom. It's embaressing to have the hatch cover on the top of your wing.
Prepare your Bellcrank, with the leadouts, pivot rod, (don't forget to make sure that there are washers between the pivot bearing and the eyelets when soldering the BC assy. If you don't you'll have a problem.
Once the gear blocks, weight box, and bottom sheeting are installed, you can turn the wing over, and install the prepared, Bellcrank and mounts. Run the leadouts to the outside of the inboard wing. Install the flap pushrod.
Install the top leading edge sheeting.
Prepare and install the center sheeting, top and bottom.
From here on, you would install the leadout slider, and both wing tips as per the instructions.
It's now time to sand and shape the leading edge. sand the rest of the wing. This basically gets the wing ready for installation in the fuselage.
Speaking of the fuselage, The fuselage that was in the kit I got, was cut with out the nose scoop. I used the outline on the plans and built a nose scoop and installed it.
Another change I did involves the stab and elevator. Originally the stab has always been 1/2 inch thick, and the elevators 3/8 inches. The idea was to provide a soft nuetral to help eliminate any hunting tendencys. Lately, we've been making our stabs and elevators the same width, 1/2". It hasn't seemed to cause any additional hunting tendencys, but it seems to help eliminate a slight hesitation when transitioning between the inside and outside loops in the eights.
It's extremely important to have correct alignment of all the surfaces, relative to the thrust line. Take your time here and get it right, it'll pay off.
Hope this answers some of the questions that might arise.
I'm wondering why everything is spinning around?