ViperDog Build Thread
#1

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The UPS man was good to me today! [8D]
He brought a ViperDog kit to replace my Mad Dog. It met it's end at the CAPS race.
The kit comes with a fiberglass fuselage, foam wing cores, and aluminum landing gear.
If you want a ViperDog just order a Mad Dog kit and add comments in the notes to send a ViperDog instead.
He brought a ViperDog kit to replace my Mad Dog. It met it's end at the CAPS race.
The kit comes with a fiberglass fuselage, foam wing cores, and aluminum landing gear.
If you want a ViperDog just order a Mad Dog kit and add comments in the notes to send a ViperDog instead.
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The nice thing about the ViperDog is that the fuselage fits the Viper (Great Planes) wing and tail.
I prefer to build my own so that will be done here in the thread.
I prefer to build my own so that will be done here in the thread.
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Kevin (Matney's Models) molds a lightweight fuselage that is also very strong.
The nose and other areas are reinforced with carbon fiber and Kevlar.
It weighs a scant 7.4 ounces.
The nose and other areas are reinforced with carbon fiber and Kevlar.
It weighs a scant 7.4 ounces.
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Kevin has listened to modelers and made a couple improvements to the original Mad Dog fuselage.
1) The tail is widened to allow internal control horns.
2) The nose fits the square back-plate mounts.
3) The landing gear block is reinforced with both carbon fiber and Kevlar.
This model should fill the bill for someone that broke an original Viper fuselage or for someone that wants to build a new model.
1) The tail is widened to allow internal control horns.
2) The nose fits the square back-plate mounts.
3) The landing gear block is reinforced with both carbon fiber and Kevlar.
This model should fill the bill for someone that broke an original Viper fuselage or for someone that wants to build a new model.
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Hey where is the rest of the build???? You wet our appetite and then leave us hanging???
Just kidding Scott, I always enjoy your build threads!!!
Just kidding Scott, I always enjoy your build threads!!!
#9

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I used three pieces of 4" x 1/16" x 48" balsa to make each wing skin.
Just trim parts to fit and tape.
Each skin was later trimmed to about 10 1/2" wide. This leaves a little overhang on both sides of the wing shucks.
Both skins were joined with a piece of masking tape. You leave about 1/8" of gap between the skins to allow for folding.
Just trim parts to fit and tape.
Each skin was later trimmed to about 10 1/2" wide. This leaves a little overhang on both sides of the wing shucks.
Both skins were joined with a piece of masking tape. You leave about 1/8" of gap between the skins to allow for folding.
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Cut a 6" x 48" piece of 2 ounce fiberglass cloth.
Tear off a 3/4" x 48" section of carbon fiber.
Lightly spray a small amount of 3M 77 adhesive to the sheeting.
Tack on the 2 ounce cloth at the wing fold (like a book).
Tack on the carbon fiber on the bottom sheeting.
Tear off a 3/4" x 48" section of carbon fiber.
Lightly spray a small amount of 3M 77 adhesive to the sheeting.
Tack on the 2 ounce cloth at the wing fold (like a book).
Tack on the carbon fiber on the bottom sheeting.
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Use a razor saw to cut a slot for the carbon fiber vertical spar.
It is a piece of 1/2" x 36" x 0.021" carbon fiber.
Mix a small amount of wing skin epoxy and dab it in place using a disposable brush.
Push the carbon fiber spar in place and dab a little more epoxy as needed.
It is a piece of 1/2" x 36" x 0.021" carbon fiber.
Mix a small amount of wing skin epoxy and dab it in place using a disposable brush.
Push the carbon fiber spar in place and dab a little more epoxy as needed.
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Some 3/4 ounce fiberglass cloth is laid on the sheeting prior to applying the finishing epoxy.
Mix about 1 ounce of finishing epoxy for each side. About a cap full of 91% alcohol is added to each cup to thin out the epoxy.
The contents are immediately drizzled on the wing panels and then squeegeed out until the epoxy covers.
Mix about 1 ounce of finishing epoxy for each side. About a cap full of 91% alcohol is added to each cup to thin out the epoxy.
The contents are immediately drizzled on the wing panels and then squeegeed out until the epoxy covers.
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The sheeting and wing cores are placed between the shucks.
Adjust parts to fit and then temporarily pin the parts together.
Tape the parts together, insuring parts are straight, and then remove the pins.
I used vacuum bags made from 4 mil thick pieces of plastic tarp. Commercial vacuum bags also work fine.
The edges were sealed with inexpensive latex caulking.
A picture of my Vacuum Pump is also shown. It was made from a refrigerator compressor, a few pieces of PVC, and uses a vacuum switch to shut off. It turns off at about 6" of vacuum.
Adjust parts to fit and then temporarily pin the parts together.
Tape the parts together, insuring parts are straight, and then remove the pins.
I used vacuum bags made from 4 mil thick pieces of plastic tarp. Commercial vacuum bags also work fine.
The edges were sealed with inexpensive latex caulking.
A picture of my Vacuum Pump is also shown. It was made from a refrigerator compressor, a few pieces of PVC, and uses a vacuum switch to shut off. It turns off at about 6" of vacuum.
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The core was removed from the vacuum bag.
Check to insure that the wing core remained true in the shucks. Adjust if needed.
Trim the leading and trailing edges flush with the shucks.
Use a sanding block to true up the edges.
Check to insure that the wing core remained true in the shucks. Adjust if needed.
Trim the leading and trailing edges flush with the shucks.
Use a sanding block to true up the edges.
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There were a few dings on one piece of sheeting.
These were fixed by applying a small amount of water to the dings.
A dings absorbs the water and return to the original shape.
These were fixed by applying a small amount of water to the dings.
A dings absorbs the water and return to the original shape.
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Draw a reference line down the center of the balsa leading edge.
I used a knife, razor plane, and sand paper to shape the leading edge.
I used a knife, razor plane, and sand paper to shape the leading edge.
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The wing was sheeted with medium weight wood and came out at 11.1 ounces.
Using light or contest wood will drop the weight a couple ounces.
Using light or contest wood will drop the weight a couple ounces.
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I spent a few minutes sanding the seam smooth using a sanding block.
A 3/4" hole is drilled in the front of the fuselage to provide access to the back of the firewall (for blind nut installation).
A 3/4" hole is drilled in the front of the fuselage to provide access to the back of the firewall (for blind nut installation).