Tips For Building Combat Wings
Following are some tips for building your flying wing combat glider.
Keep it Light!
You can always add lead to a light weight glider in heavy wind conditions, but you can’t make an overweight tanker lighter when the winds are low and lift is light!
I’m using a Cheap Shot as an example, but this applies to all Combat Wing gliders. Using a 275mah battery pack, a Hitec Supreme 8Ch. receiver and 2 standard servos, like Futaba S-148 or Hitec HS-422, your Cheap Shot should weight 18 oz. or less the first time you throw it off the hill. It is possible to build a Cheap Shot that weighs less than 16 oz. using Lithium batteries and mini servos, but this can get expensive for combat.
With time and repairs, your glider will get heavier, but 18 oz. is a good target for a new Cheap Shot. To achieve this, there are 2 things that you must use sparingly: spray glue and reinforced tape. The poly shipping tape has an amazing amount of tensile strength, and will provide all the structural strength needed, so reinforced tape is only needed for added durability in places that take a beating, like the nose of the glider.
I avoid using reinforced tape along the full length of the leading and trailing edges. Why? The entire wing tip of the Cheap Shot is behind the C.G. Any weight here has to be balanced with additional weight in the nose to get a proper C.G. I typically use 2″ wide reinforced tape along the leading edge, but only out half way. The rest is poly shipping tape. The same goes for the trailing edge. I use 1″ wide reinforced tape along the trailing edge, both top and bottom, but only out half way.
Covering with Color Tape
Color shipping tape is not the most glamorous way to cover a glider, but it is the cheapest, and you can make it look pretty good using these tips.
Make sure it sticks!
Always spray any foam surface with 3M-77 Spray Adhesive before applying Color Tape. Nothing sticks to EPP foam without the 3M-77 Spray Adhesive, and the white EPS foam can use some help too. I even spray a light coat on the elevons before applying Color Tape.
When applying the tape, stretch it as much as possible, and keep the air bubbles out. I first cut a piece of Color Tape to the length I need, plus a few inches. Position the tape over the location where it will be applied. Stick one end of the tape to the glider. I usually stick down the right end of the tape first because I am right-handed. If you are left-handed, you should stick down the left end.
Now apply tension to the left end of the tape, and use the palm of your right hand to stick the tape down to the glider, by ironing the tape down, right to left. This is a continuous motion, while you are tensioning the tape with your left hand. The tension adds strength to the finished product, and helps to eliminate those ugly air bubbles.
Use the blocks, Luke!
Always use the foam blocks to cradle the wing sections while covering the glider. This will insure that the finished glider will be straight and true.
Light colors first!
When covering with multiple colors, apply the lighter colors first, then overlap darker colors on top of the light colors. Some color bleed through is inevitable, but this will keep the bleeding to a minimum.
Now, really make it stick!
Here is the real secret. After all the Color Tape has been applied, make up a small stick with a straight, but smooth edge. I like to use a Popsicle stick for this. I sand one edge round with a sanding block, then use this rounded edge to iron down the Color Tape to the foam. Use the stick like a squeegee to iron out any remaining air bubbles and smooth the tape to the foam. It only takes a few minutes to do this to a completed glider, and it really makes the whole covering job look a lot better. It will also increase the life of your glider by making the tape stick down that much better.