Wing tip alignment

Hornet2008 · #1 06-09-2014, 04:25 PM

Searched the forums but couldn't find anyone who had made the same mistake. I attached my wing tips without aligning them with the ailerons. The port tip is 3/8th" low but the starboard one is 9/16th" low. I have used piano hinges to join them to the wings and they look good, however, there is a serious alignment issue. I've read the tips have to be in trail with the flaps and aileron for stability. I saw a couple of posts where the tips have been cut across the trailing edge and up the sides and re-glassed. Is this a possibility?

R. Daniels · #2 06-09-2014, 09:36 PM

Pete, I have slit wingtips on several project RV's to take care of small misalignment issues, I'm talking about maybe up to 3/16" or so. You have a major alignment problem. A common mistake it is to install the tips prior to installing the wings! The wings have to be installed, flaps set at proper trail and matching each other and the ailerons adjusted to match the flaps. Only then can the tips be installed. I would suggest removing the tips, sealing all holes with epoxy and milled glass mix and start over again. Not only do the tips have to be in trail with the ailerons but the tip trailing edges need to be inline with the aileron trailing edges. To clarify, I mean getting down and sighting down the tip, aileron and flap trailing edges. The only way to achieve that is to start over. What you currently have is not only unsightly but will have a drastic effect on roll trim.

Dbro172 · #3 06-09-2014, 09:46 PM

You did set the ailerons by using the aileron alignment tool from section c-c on page 15 right? You can't just run a straight edge off the top skins, or match the flaps....

Hornet2008 · #4 06-09-2014, 10:36 PM

Thanks Rex and Derek. Yes, the flaps and ailerons are set to the W-930 tool and the wing chord indicator. I actually did the reverse Rex, I set the wing tips prior to setting flaps and ailerons, hence the problem I now have. Re-doing the whole thing is an option but I've read somewhere( can't find it now) that someone cut across the trailing edge and down along the outboard centre line using a fine tooth blade in a jigsaw. He then adjusted the trailing edge of his wing tips. Is this possible or will it affect the flying characteristics of the wing? I can almost bend them up into position but it buckles the top side of the tip.

bruceh · #5 06-09-2014, 11:34 PM

I don't think that splitting the ends will work with the amount of correction you need. It would only impart a bunch of unwanted twist to the tips.

I would drill out the piano hinges on the fiberglass tips, patch up the holes then redrill. You can offset the new holes in the tips and on the existing hinge section between the original holes.

The wing tips can be moved around as it sits inside the wing skins at the leading edge. Trailing edge end will move quite a bit up or down as you move around the wing tips at the leading edge. Once you get the aft trailing edge aligned with the ailerons, clamp it down and start drilling/clecoing.

KRviator · #6 06-10-2014, 03:10 AM

Quote:

Originally Posted by Dbro172

You did set the ailerons by using the aileron alignment tool from section c-c on page 15 right? You can't just run a straight edge off the top skins, or match the flaps....

I'm away I'm my plans at the moment, but I'm fairly sure the tool you're talking about only provides the necessary movement at the bellcrank - not the aileron - so the length of the aileron pushrod will affect the final position of the aileron even with the bellcrank in the proper position.

To set the aileron, you need to run a straight edge off the top of the wing, and have the top skin of the aileron up against it, IIRC...

Hornet2008 · #7 06-10-2014, 04:51 AM

Unfortunately I have drilled 3/16" flox holes in between the soft rivets and filled them with flox. Probably won't be too hard to get the old hinges out. I had planned to use a long length of AL angle clamped under the aileron and flaps to align the wing tip once I cut it( haven't decided to cut as yet). Worst case scenario is to replace both wing tips. Hope it isn't going to come to that. How is phase one going Bruce? I often visit your great website, there is a wealth of information there.

scrockard · #8 06-10-2014, 07:45 AM

I too split my wingtip to fix my mis-alighnment. I know my eye would go there everytime if I didn't fix it.

Mark Dickens · #9 06-10-2014, 08:14 AM

I'd just remove everything, lay down a couple of plies of fiberglass cloth over the existing holes inside the tips, fill the existing holes with flox and start over. The great thing about fiberglass is that you can fix mistakes most of the time. All it takes is patience and a willingness to do it right

Dbro172 · #10 06-10-2014, 08:18 AM

Quote:

Originally Posted by KRviator

I'm away I'm my plans at the moment, but I'm fairly sure the tool you're talking about only provides the necessary movement at the bellcrank - not the aileron - so the length of the aileron pushrod will affect the final position of the aileron even with the bellcrank in the proper position.

To set the aileron, you need to run a straight edge off the top of the wing, and have the top skin of the aileron up against it, IIRC...

There are two tools; the aileron alignment tool and the bellcrank jig. The ailerons are NOT set by running a straight edge off the top wing skins. (At least on the -9)

It is possible to set and rig the ailerons and the wing tips without ever installing the flaps, or the wings on the plane.