Wingtip Hinges

[Richard Connell]

For those of you that have chosen to attach your tips using piano hinge, how have you installed the rib in the tip?
I imagine there is conflict between the hinge and the rib if you extend the hinge to the rear of the wing skins. Particularly on the top.
I?m also expecting to swap the ribs so the flanges are outboard to allow insertion of the pin.
Thanks
Richard

[bullojm1]

Hi Richard,

Everything you need to know is right here (at least for a-7/8/9, but same should apply for a -10):

http://rvplane.com/pdf/WingtipHinges.pdf

Mike B

[Richard Connell]

Originally Posted by bullojm1

Hi Richard,

Everything you need to know is right here (at least for a-7/8/9, but same should apply for a -10):

http://rvplane.com/pdf/WingtipHinges.pdf

Mike B

Thanks Mike. That?s a good reference.
I did this on my -7 so I?m up to speed with the various methods.
The problem on the -10 is that the tip rib extends further forward plus it has a reflex in it. So one needs to either shorten the tip rib flanges, shorten the hinges, or come up with some other clever solution. Curious as to what others have done to address this specific conflict.
Cheers

[Bill Boyd]

I just finished installing the hinges using Mike's excellent directions. I've put off figuring out how to install the ribs and secure the pins. I guess I was thinking it was necessary to rig the ailerons and then match the wingtip T.E.'s to them, and lock in any necessary twist by installing the ribs at that time.

If nothing else, this thread makes me think I should have looked ahead a little more at the rib installation - although this is probably an area where one could "wing it" and depart from the plans a bit without issue, as long as the wing tip closure and hinge pin capture is engineered soundly.

[Bill.Peyton]

I reversed the ribs left to right and upside which leaves a space to secure the hinge rod material. This required a little trimming of the rib. I drilled the retaining bolt and safetied them to prevent them from backing out and interfering with the aileron movement

[IMG]IMG_1661 by Bill Peyton, on Flickr[/IMG]

IMG_1669 by Bill Peyton, on Flickr

[Scott Hersha]

I cut off the part of the rib flange that coincides with the aft part of the skins, and made a new flange section that points outboard in those two areas. These pieces need to be spaced away from the fiberglass slightly so that it sits on top of the hinge half where it is riveted through the hinge half into the fiberglass. This allows the hinge pins to nest nicely in the inside apex of the inboard facing rib flange. I mounted a couple hinge eyelets to use as guides to ease attachment, and there is a slight load on the pins with a 90 degree bend in the aft end so that they snap into the tooling hole in the back end of the rib to hold them in place. I can remove a wingtip in 30 seconds with no tools.

[Dorfie]

Richard,
I swopped left and right sides.
You have to cut the front ends to fit. I cut it such that a tab was left that was bend 90 degrees for strength.
It is not uncommon that you have to split the trailing end of the wingtips to align with the aileron after that was aligned with the flaps in reflex position, so leave this to the very end. Only install the ribs after the above was done.
I secured the hinge pins similar as shown by Bill Peyton. There is a nutplate behind that bolt in my installation.
Johan

[rdrcrmatt]

I also did what was mentioned above. I swapped left/right ribs so there was room to secure the piano hinge.

[leok]

I am just curious as to how often the wing tip will need to come off? I recognize 40 screws is a lot to remove, but does the tip need to come off enough to justify the modifications? Or is the motivation strictly aesthetic?

[9GT]

Originally Posted by leok

I am just curious as to how often the wing tip will need to come off? I recognize 40 screws is a lot to remove, but does the tip need to come off enough to justify the modifications? Or is the motivation strictly aesthetic?

I had mine off and on a few times before I sold my RV-10 for various reasons. I plan on the hinge method when I finish up my wings on my RV-9A. I already removed the nutplates the previous builder installed. In addition to a much cleaner look the hinge method provides, it makes it really easy to remove the tips if you ever need to. The screw system works good, but looks ugly, tenancy to strip the screw drive on occasion, and finally twists the paint underneath the screw head. Then it starts looking REALLY ugly with chips of paint missing around the screw dimples.