Al Stein

Well, at least you'll never miss that inch on the Senior Kadet wing... it's got an inch or two to spare.
Now, where is the mismatch happening?

Here's how I join a 3-channel wing...

I pin the two root ribs together and drill 1/4" alignment holes near the leading edge and trailing edge of the two aligned ribs.

I build each wing half with the upper center sheeting and center/root rib left off.

For each wing panel, I lay the panel flat on the table and use a carpenter's square to align the root rib square to the main spar (front to rear, that is) and a dihedral guage to give it the right setback angle (it should lean away from verticle, into the wing). It sometimes takes going back and forth between adjusting the squareness and adjusting the dihedral angle... just repeat until it measures up right and the rib isn't bending. (If any stresses like too-tight spar notches or spacing are making the rib bend, carefully enlarge the notches or the spacing as required to let it sit flat in its place. Also, try and make sure that the distance from the wingtip to the bottom of the root rib is the same for each wing panel.

Then I glue the root rib in place and make sure it's still angled correctly in both directions.

Next I trim the protruding spar ends as close as I can, and then sand them flush with the face of the root rib. With the root rib in place, it holds the spars so you can sand them -- it's real hard to sand them into a flat plane before then. What you get will be a good flat root at the right angle.

OK, we're coming down the home stretch now... Make lotsa room!

I insert a short 1/4" dowel into each alignment hole of the root rib of one panel, then I prop up that panel at the total dihedral angle. (I.e. if the instruction says 3-1/2 inches under each tip rib, I prop one tip up by twice that -- seven inches. If it says to prop up one wing tip 5 inches, I prop up one wing tip 5 inches.)

Now I glue up the root rib of the other planel and align it against the root rib of the panel that's already propped. (The alignment is pretty much automatic since you made exactly aligned holes and have dowels connecting them.) Let that dry. This should be done with glue that has to dry, not instant stuff... or you may misalign and end up recutting and losing another inch of wing. And it should be done on wax paper or such.

Once the root ribs are joined, the whole thing is delicate, but it is aligned... THEN you can cut slots for dihedral braces and epoxy those puppies in place. From there, just finish the sheeting and that funny looking block on the front and you've got yourself a wing.

OK, what'd I forget?

FHHuber

I'll often block the two wing panels at the correct dihedral angle, with the spars offset, overlaped. Bottom spar cut to correct length, top spar too long. Bottom sheeting in place, top sheeting and root ribs not in yet. The back of one wing's main spar resting against front of the other. With the bottom sheeting as the guide for having the wings spaced, I razor saw straight down through the top spars and bottom spars. The wings fit together perfectly every time.
(Its easier to show than describe...)

You just about can't install the root rib correctly until the spars are cut unless you go through a LOT of work with the carpenter's square and dihedral guage. This method... the center ribs gets installed flush with the perfectly cut spars.

You can laminate all root ribs together then glue that into one wing... along with the dihedral brace(s) let it set up, then join up the wings. the laminated root rbs guide the spar, LE and TE locations, the dihedral brace guides the angle between wings. It gets VERY easy from there. [img]i/expressions/face-icon-small-wink.gif[/img]

30 min or 2 hour epoxy for joining the Kadet Sr wings. (2 hour preferred) Quicker setting epoxy won't gve you time to do it right. LOTS of pins and masking tape to hold things in place! (stick pins in a bar of soap before sticking in the wing... they slide out of the epoxy easilly after the stuff is set up. Twist then pull.)

rcalfred

One trick I learned from a Dave Platt video is to make the wing spars before making the rest of the wing. Usually the spars have a plywood joiner between them. Assemble the spars for both halves of the wing to the joiner with the correct dihedral in them. When the epoxy has cured, build one half of the wing in the usual way including the root rib(s). When one half is done, lay the other half of the wing spars down on the plan and complete the wing. Perfect alignment and the root ribs are at the correct angle. Since you already have the two halves done, this trick is too late for you. But, try it for next time. Regards,