grosbeak

You may have come across my AMR Trainer 26 build thread. I have run into a problem and am starting a new thread in the hopes of reaching more people.


During the build up of the wing I test fit it to the fuselage a few times; in this instance I pinned the front of the wing using a couple of transfer punches. All was good.





It's when I got to the step in the manual where the wing is finally fit to the fuselage that I started running into problems.


First of all, the wing pin holes didn't line up like they had before. The front of the wing was properly centred with the port dowel in place...





... but the starboard hole did not line up.





I wracked my brain for a reason but couldn't figure out why. This is still nagging at me. Since the pin holes are already part of the wing (not just the balsa leading edge but the underlying structure as well) I figure I had no choice but to relocate the hole, which I did (I don't know how the new hole ended up lower than the original but it doesn't seem to affect fit and can be addressed later if need be).





With this done the fit at the front appeared to be fine.





At the back I centred the wing using the method described in the manual - measure from each wingtip to the tail, adjusting the angle of the wing until the measurements are equal. I did that - both wingtips are 1331 mm from the tail. However, now the wing alignment at the rear is off - the centre line of the wing is a few mm to starboard of the fuselage centre line.





This is where I stopped. Things are not right at this point and I have not yet come up with a way to fix them. Your advice would be appreciated.

TomCrump

Is the wing centered in the fuselage, measuring from the wingtip to the fuse, at the wing root ?

sensei

Are both wings exact in length at the leading and trailing edges?

Bob

grosbeak

Tom, I will check. I will take three measurements for each wing - leading edge, main spar, trailing edge.

Bob, could you please give me a little more detail? Are you asking if the wings are exactly the same length?

sensei

Yes but measured for length at both the leading edges and both the trailing edges.

Bob

grosbeak

Ah, yes. I will check that.

box car

I bet you did not use a square to build your wings

jeffo

My Feedback: (68)

Is your fuse straight?Construct a straight line from the leading edge center line to the center line at the end of fuse.See where the trailing edge center line ends up.Personally,your worried about nothing.As long as the wing is straight,and set at the proper incidence in the saddle.If the rotation is with in a few mm,you'll never notice it.jeffo

grosbeak

Care to make it interesting?

grosbeak

I have heard back from Dany at AMR and he had some very nice things to say about my build. He also said, "... you could have the wing off/crooked by 1" at the saddle section and you would not even see a difference when flying. Make the wing fit so that it looks nice for you."

I checked the fuse and I'm satisfied it's straight and true. I squared the wing to the fuse using wingtip-to-tail measurements and marked the anchor plate for the wing bolts. There's plenty of room for the starboard wing bolt (and T nut if I choose to use one).



Thanks for your contributions, everyone. I'll be back on the build shortly!