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B Model Wing Specs

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  • B Model Wing Specs

    Good Evening!

    I'm currently working on a spreadsheet for the ribs in the B Model wings and I am stumped by the flanges for the Aileron Pocket Ribs. It says 9 Left and 9 Right but doesn't specify (or I can't locate the information) if all right flanged pocket ribs go in the right wing, etc. or if they vary based on position as most of the other ribs do. My guess, based on the layout of the other ribs, would be that the flanges go outboard with the exception of the ribs that define the space for the aileron hinge mounts. In those locations the flanges would face away from the space. But that is merely a guess. Looking forward to any insight. Thanks in advance!

    Todd Weld
    Plans #1515B
    www.facebook.com/N729TW/

  • #2
    I don't have my plans to hand at the moment but IIRC there are small arrows showing the rib orientation .....

    Comment


    • #3
      There are arrows on most. The aileron pocket ribs seem to be the exception. Common sense suggests an order based on the way the other ribs are laid out in the wing, but I'd like someone with more experience than myself to validate that assumption.
      Todd Weld
      Plans #1515B
      www.facebook.com/N729TW/

      Comment


      • #4
        I built my A-wing with all pocket rib flanges pointing toward the pocket. My remembrance is that it was easier to rivet them positioned that way. Also looks better.

        Comment


        • #5
          Another data point... the photo below is a Patrol wing from the factory. Looks like the flanges point towards the hinge mount. I agree that Ray's method would look better.

          Screen Shot 2019-03-11 at 8.20.24 PM.png
          Brooks Cone
          Southeast Michigan
          Patrol #303, Kit build

          Comment


          • Ray Strickland
            Ray Strickland commented
            Editing a comment
            I may have not made myself clear. Flanges pointed towards the hinge pocket (as in the photo above) is the same, I think, as flanges pointed toward the hinge mount. “Looks better” may be a misstatement.

        • #6
          Thanks guys! Looking at that picture it is apparent how that setup would make riveting easier. So in the end it comes down to ease of maintenance and building rather than anything structural?
          Todd Weld
          Plans #1515B
          www.facebook.com/N729TW/

          Comment


          • #7
            Here is the link for the spread sheet I've been working on to keep track of the wing rib information for the Model B wing. I've found Model B specific data spread out or difficult to find and hope others in the same boat may find this useful. Areas where the plans seem unclear are marked with a (?) and I welcome any corrections or suggestions for the information presented.

            https://docs.google.com/spreadsheets/d/1neIKKv8xP6BriQqLrJN6nVoGK3yZGXzLEcqYtbcCWkc/edit?usp=sharing
            Todd Weld
            Plans #1515B
            www.facebook.com/N729TW/

            Comment


            • #8
              Originally posted by Weldingiron View Post
              Here is the link for the spread sheet I've been working on to keep track of the wing rib information for the Model B wing. I've found Model B specific data spread out or difficult to find and hope others in the same boat may find this useful. Areas where the plans seem unclear are marked with a (?) and I welcome any corrections or suggestions for the information presented.

              https://docs.google.com/spreadsheets/d/1neIKKv8xP6BriQqLrJN6nVoGK3yZGXzLEcqYtbcCWkc/edit?usp=sharing
              This is an awesome resource...Thanks for posting it...

              Comment


              • #9
                Todd your spreadsheet is usefull. One change you may consider is to define the flange direction as inboard or outboard instead of left or right. This is in keeping with accepted aircraft terminology.
                One other column you may consider is which side of the rib web the attach angle fays to and the direction of the attach angle leg that fays to the spar. I struggled with some of this on my Patrol. Had to look at a lot of pictures to get it right. Wish a spreadsheet like this came with the drawings.
                Gerry
                Patrol #30 wings

                Comment


                • #10
                  Thanks for the input, Gerry! I went back and forth with the left/right or inboard/outboard decision. I went with left/right to simplify jig selection. A left flange will always use the same side of the form block regardless of which wing it will end up on. The side used to form an inboard flange depends on which wing the rib belongs to. When it comes to assembly, I agree inboard/outboard is not only better terminology, but would also add clarification. Maybe I need a fabrication and an assembly tab I imagine I am going to want the information on attach angles compiled as well so will work on getting that in there. Thanks again!
                  Todd Weld
                  Plans #1515B
                  www.facebook.com/N729TW/

                  Comment


                  • #11
                    Originally posted by Weldingiron View Post
                    Thanks guys! Looking at that picture it is apparent how that setup would make riveting easier. So in the end it comes down to ease of maintenance and building rather than anything structural?
                    Yes, it's just easier to build that way. Once complete, you will never notice whether the flanges point in / out. Its a small detail, and 95% of the pockets are out of sight.

                    Comment


                    • #12
                      Its obvious to builders who have been going over the plans for awhile...but for new builders there are some simple things that could help....

                      indicating the rib to use as the height of your spar.....
                      Last edited by way_up_north; 04-04-2019, 10:25 PM.

                      Comment


                      • #13
                        Originally posted by Weldingiron View Post
                        Here is the link for the spread sheet I've been working on to keep track of the wing rib information for the Model B wing. I've found Model B specific data spread out or difficult to find and hope others in the same boat may find this useful. Areas where the plans seem unclear are marked with a (?) and I welcome any corrections or suggestions for the information presented.

                        https://docs.google.com/spreadsheets/d/1neIKKv8xP6BriQqLrJN6nVoGK3yZGXzLEcqYtbcCWkc/edit?usp=sharing
                        Resurrecting this thread... I too really liked this spreadsheet, and am developing a very similar tracking system for my rib build. One note for Weldingiron... I independently went through the same exercise and get the exact same set of answers, save one. I believe what you have listed as "Center Rib 9" in this spreadsheet should show only 1/8" trimmed from the forward end, not 1/4". In my plans (sheet 2B), this is center rib #11 (the plans number the two false ribs as #3 and #4). If I compare against the rear spar cap locations on drawing 5B, it looks to me like the spar cap taper occurs prior to this rib. The plans show the caps on the front of the forward spar extending past this spanwise location, but the caps on the aft of the spar (where the forward end of the center ribs attach) look to me like they taper down to 1/8" prior to center rib 11 (9 in your sheet). Perhaps you could check me? Otherwise I get the identical spreadsheet to what you have.
                        4-Place Model 'B' Serial 1529B (with many years to go...)

                        Comment


                        • #14
                          Thanks, nborer! On closer inspection it looks like you are right and I updated the spreadsheet.
                          Todd Weld
                          Plans #1515B
                          www.facebook.com/N729TW/

                          Comment


                          • #15
                            There was a suggestion log ago that there be a sticky thread with Bob's recommendations. One suggestion he gave me was that you do not pre cut ribs accounting for capstrips. I have found his suggestion to be a good one. If you buy ribs from Mark, they may all be perfectly the same. When you bend your own ribs there will be variation. If you hold off the cuts for the capstrips you can swap ribs around for the best average fit on the spar web. A rib slightly larger can be moved to a location on the spar web that is slightly larger. You loose that discretion if you cut early.

                            It is also easier to make a "factory like edge" if you do not cut early.

                            The last step of putting a notch can be done in seconds without compromising the edge that touches the spar web.
                            Attached Files
                            Stan
                            Austin Tx

                            Comment


                            • nborer
                              nborer commented
                              Editing a comment
                              That’s good insight. Regarding the notches in the picture above, is this something you do to every full-length rib? Then, when you trim to size, you only need to trim the excess rib web to fit? That’s a neat idea - the only part of the rib that needs the full length is the part that is riveted to the spar attach angles...
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