Wingtips arghhh heeeelp!!!!

Discussion in 'Tips, Tutorials & Tools' started by GT5500, Nov 20, 2006.

  1. GT5500

    GT5500 Member

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    Curently I am butchering a Fleet Cornell by Ken Uhrig and I have got to the wings. Now here I have hit a problem, the wings are in one piece and only have a spar and one former for internal support. Now the wingtips are intended to be rounded over but they have no slits in them like the halinski ones. When I tried to round them over I just end up with a bulge somewhere as there is too much material. Should I just cut some slits into it? or is there another way, I have scanned the wing so I have spares but I want to get it right please help.
  2. cgutzmer

    cgutzmer Guest

    can you post the scan of just the one part and maybe a pic of how its turning out for you?
    Thanks
    Chris
  3. shrike

    shrike Guest

    Use a rounded stylus (baby spoons work) anda soft pad like a vinyl eraser to gently curve the wingtip into shape from the backside. A little bit of rubbing and some patience and you will be surprised at what you can achieve.
  4. GT5500

    GT5500 Member

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    Here is the part
    [​IMG]
  5. cgutzmer

    cgutzmer Guest

    Its part of the wing! I didnt realize that.



    I dont think any wing i have ever done that had the wing tip built into the wing iteslf like that I even attempted to get rounded. I dont see how you could do it. To get the rounded look you would almost have to cut thin slivers of paper out and round them down kind of like how some plane nose cones are done (but not to that extent of course)

    a pic if a real wingtip in case you hadnt seen one....
    http://www.pimaair.org/Acftdatapics/imge036.jpg

    Chris
  6. Gil

    Gil Active Member

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    This Might Help

    Making rounded wingtips isn't too difficult but requires patience and a go slow approach. First the navigation lights need to be removed and applied later on. There are several methods that achieve similar results but I've found that sealing the surface to control "pulping" is an important first step. The method described here uses controlled softening ("pulping") of the paper to sculpt it into the desired wingtip shape.

    Start the paper forming process by curving the tip plates as much as possible using a suitable burnishing tool and a vinyl eraser. Coat the edges of the curved plates with PVA and let dry. Assemble the wing leaving the tips unglued. Once dry the tip forming process can begin. Apply PVA sparingling on the edges of both tip plates and allow to nearly dry. The glue will become very tacky and will penetrate the paper making it softer and easier to form. When the glue is nearly dry start closing the two edges together starting at the trailing and leading edges working toward the center. If a bulge or wrinkle appears work it out by tapping lightly on it with a spoon or burnishing tool. Go slow here and slowly work the edge to curve over and blend the two plates together. Make sure to keep the tools clean. Apply PVA as required and allow to tack-up to seal-up edges that are not quite closed. A hair dryer or heat gun helps to speed up the "tacking" of the PVA.

    The following image shows a 1:87 Piper wing formed using this method.

    -Gil

    [​IMG]
  7. GT5500

    GT5500 Member

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    Gill I am familiar with your method and I was attempting to use it, the problem I keep getting is that the wing tip bunches up as there is no where for the excess material to go. If I try and smooht out the bulges I just end up with creases.
  8. cmdrted

    cmdrted Active Member

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    You can cut some small relief wedges in the tips. You should still burnish the tips as Gil described, and probably do the pva glue technique also when the tips have been shaped also. Sometimes burnishing isn't enough when you have too much material at an area. when you cut these wedges look at where it is puckering up. that is where the wedges need to be cut. You can butt glue these edges or use thinner paper on the inside to glue up the wedged section.

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  9. Gil

    Gil Active Member

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    Bulges will appear and need to be "tapped down" with the burnishing tool. A key insight into this method is using light repeated taps along the edges to "even out" the curling process. This technique does require some practice to master requiring a slow and deliberate approach. Cutting "darts" as cmdrted suggests also works but will show in the finished tip, but does get the job done.

    -Gil
  10. GT5500

    GT5500 Member

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    Thanks for all the advice, I think I will go with the wedges though as I have tried without them and I can't get enough of a curl without bulges. I can curl it a small amount but to get a large curl on it the bulges appear and no amount of burninshing will remove them.
  11. cmdrted

    cmdrted Active Member

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    There is another approach which involves a lttle fitting. you would need to cut the tips off, place some type of connector strips to the stub of the wing and then cut the tip parts a little smaller so you can curve them both upper and lower. The best illustration I can think of is look at the L-29 Delphin thread go to the wing or stabilizer bit and look at the tips. These were made as above. It does eliminate the wedge sections as Gil pointed out, and it actually is easier in the long run. You still need to burnish a curve in the part but it does make it "seamless " at the very tip. Also most real wings have a frame piece near the tip so it is actually a more accurate depiction of the wing tips.
  12. Gil

    Gil Active Member

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    Another Method Might Work

    An alternate method uses an internal form to shape the wing tip. It requires bonding a couple of layers of cereal box cardboard together followed by sanding the edge to shape. Coat the wing tip bow area with wax. The wing is then folded around the form and tacked in place with Tack-It-Over-&-Over glue. The tips can now be burnished together with ease and without bulges.., The folllowing is an image of a wing tip finished this way.

    -Gil

    [​IMG]
  13. cgutzmer

    cgutzmer Guest

    I think we have a wing tip master in our midst! :) Those are great tips on how to make tips!
    Thanks,
    Chris
  14. cmdrted

    cmdrted Active Member

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    Here is a graphic of another approach, cut the tips off make connector strips, trim up the little halfmoon wedges after you burnish a curve in them

    Attached Files:

  15. Sumato

    Sumato Member

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    Posts and threads like these are EXACTLY why I come to these forums. I love that we can and want to share great techniques and support for one another. I know I learn something everyday from you guys. Thanks!