Fixing nick in AT fin leading beveled edge

Discussion in 'Techniques' started by OC_Rocket_Man, Feb 15, 2018.

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  1. Feb 15, 2018 #1

    OC_Rocket_Man

    OC_Rocket_Man

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    I have an old AT Initiator that I am going to clean up and get flying again.

    The leading beveled edge of a fin has a nick in it. Small but noticeable.

    What's the best way to fill the nick to make it pretty again? Can I use a little glob of CWF and sand to shape?

    20180215_142112 (002).jpg
     
  2. Feb 17, 2018 #2

    bradycros

    bradycros

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    Yep. After sanding, soak some thin CA into it and sand again.
     
  3. Feb 17, 2018 #3

    Marc_G

    Marc_G

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    +1 on the CA impregnation bradycros suggested. I would sand it roughly to shape first, then final sand after the CA.

    Also, I've found that paint pens can be used to coat such repairs, reducing the need to respray in some cases. They come in various thicknesses. I have several colors, but white, black, and red get a lot of use. A few coats of white paint pen, and you might be good to go.

    Here's one example, though there are lots of other colors and pen point styles:

    https://www.amazon.com/dp/B0018N62SW/?tag=skimlinks_replacement-20
     
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  4. Feb 17, 2018 #4

    Steve Shannon

    Steve Shannon

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    If you want to fill that nick so you don’t have to sand it back so far put thick CA on it then add baking soda.
     
  5. Feb 18, 2018 #5

    OC_Rocket_Man

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    Sorry for the remedial question, but what is the premise of the baking soda? Easier to sand? Reacts with the CA?
     
  6. Feb 18, 2018 #6

    dhbarr

    dhbarr

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    Just provides bulk.
     
  7. Feb 18, 2018 #7

    Steve Shannon

    Steve Shannon

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    It reacts with the CA as an accelerator and provides bulk, making it quick to finish.


    Steve Shannon
     
  8. Feb 18, 2018 #8

    OC_Rocket_Man

    OC_Rocket_Man

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    Thanks everyone for the tips!
     
  9. Feb 18, 2018 #9

    Trident

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    If you want a product that will fill anything, try a can of Bondo. Not the Spot Putty, but the can of resin used in body repair. I had tips of plywood fins get crunched (“smooshed” is the description that might best describe the injury ...). I needed to form a new, sharp-edged tip, and using regular epoxy would have been harder to use, and have it keep its shape.

    The Bondo dries really fast, like in a minute or so it becomes difficult to do any additional forming. But this is maybe it’s best feature. Mold it by hand and it will keep its shape with hardly any wait. And that means no sagging. It seems to bond to anything. My daughter has an old mid century modern laminate sideboard. It had cracks and voids in the laminate. I fixed it with Bondo. It sanded pretty well. We then sanded the whole piece, and she primered, and painted it. Looks like it never was repaired.
     
  10. Feb 23, 2018 #10

    OC_Rocket_Man

    OC_Rocket_Man

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    CWF and thin CA. Came out great.

    Thanks for the tips!
     

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