Just started putting this ARF together. The instructions say there should be 1 3/8" dihedral in the wings. Here is the problem: With the wing fitting solidly to the wing centerpiece, there is only 3/4" of dihedral. If you pull the wingtip up to get the 1 3/8" dihedral, there is a small gap in the bottom of the joint. Question: Should I glue the wings solidly to the centerpiece and only have 3/4" dihedral or should I pull the wingtip up and acquire the entire 1 3/8 as the instructions say and live with the weaker joint? I guess what I'm really asking is it really that big of a deal whether or not it has 3/4" or 1 3/8" of dihedral?
If anyone has put this particular plane together and can help me with this, I really would appreciate it. Thanks a lot.

You may need to sand the joiner at oposing corners slightly, to get the desired angle for them to fit.


This is the section in the GP 182 manual, and it is vague on obtaining correct dihedral, and it seems your are limited to the shape of the joiners.
Less dihedral may be ok but I would wait for a better answer to that, as the type design may require it to avoid snaps/stalls


� 3. Locate the hardwood wing joiners. Test fit the wing
joiner into the right wing panel and the right side of the wing
center-section. The joiner is positioned so 1/3 is in the wing
center-section, and 2/3 is in the tip panel. A snug fit of the
joiner is desirable. If the joiner does not fit properly, lightly
sand any uneven surfaces of the joiner edges and sides.
Repeat this step to check the fit of the other wing joiner in
the left wing panel. Label each wing joiner for orientation
and the side that it is to be used on.
flat on your building surface, measure the distance from
your work surface to the tip of the wing outer panel to make
sure you have the correct amount of dihedral as shown in
the sketch. After the epoxy has cured, repeat this step to join
the left wing panel to the wing center-section.

Wornboots,

With the joiners in place, and the two pieces pushed together with the centerpiece spar and the wing spar flatly against each other with tight joints on the top and bottom, I have 3/4" dihedral. However, there is enough free play in the joiners that I can pull up on the wing piece to achieve the 1 3/8" dihedral that the book calls for, but there would be a small gap in the bottom of the joint. If I apply the epoxy, I could hold this in place with no problem until it sets up. The epoxy would harden, filling the gap. But I am wondering is this the correct way to do that, or should both spars fit flatly against each other thus having about half the dihedral as the book calls for? In other words, I can achieve the dihedral without sanding the joiners, but the two spars would not be flat against each other.
Any further help? By the way, thanks for the reply.

I built one several years ago. I believe it was necessary to sand the joint faces to get them flat with no gaps and the correct dihedral (plus or minus a little bit). The plane flew very will with a Saito 70 until I re-kitted it. It flewso well I bought another which will be assembled shortly.

Normally when the gap is eccessive I will try to sand the joining faces to get as less open space as I can, and also the joiners as needed. You could fill the gap with epoxy but its not adding a great deal of strength, and it would not stay in place while adjusting dihedral as the book shows. (if you have gaps after joining the wing you can fill those also) But the Idea is to have solid mating surfaces.

As hopkimf refers to above the faces should fit as best as posible'

There should have been a built in angle to the sections to allow this, but not allways the case.

Hey, thanks guys. Looks like I have myself a little sanding to do on the spars. Again, thanks for the help.

Don't worry about the gap as the epoxy willharder stronger than you think. I've been flying mine with a little bit of gap and no problems over many flights. This is a great ARF and you'll love it.

Thanks Mercielago