RE: ViperDog Build Thread
 

Contest grade lightweight wood is used for the wing tips.

I've pinned the tips in place and am tracing the outline for later trimming with a scroll saw.

RE: ViperDog Build Thread
 

Looking good Scott!

RE: ViperDog Build Thread
 

The wing tips were roughed out using a scroll saw.

They were attached with 5-minute epoxy.

RE: ViperDog Build Thread
 

Slots were made for inserting 1/64" plywood.

The plywood is glued in place using thin CA.

RE: ViperDog Build Thread
 

The tips were roughed out with a sharp knife and a sanding block.

RE: ViperDog Build Thread
 

A piece of peal ply (nylon fabric) is cut to cover the wing.

RE: ViperDog Build Thread
 

Ailerons are marked off on the top sheeting.

A piece of satin is used for the hinge.

Apply a thin layer of Skin It with a squeegee and then apply the fabric.

RE: ViperDog Build Thread
 

A layer of 3/4 ounce fiberglass cloth is laid on first.

The center sections are reinforced with additional layers of 2 ounce cloth.

There are three layers on the bottom - 9" wide, 6" wide, and 3" wide.

The top has a 6" wide piece and a 3" wide piece.

I prefer to apply the wider pieces first. Later apply the more narrow pieces.

RE: ViperDog Build Thread
 

Mix two portions of Skin It epoxy. Each should be about 1.25 ounces.

Immediately pore the epoxy on a side and squeegee it out. Do the other the same way.

After the epoxy is smooth, slide the wing in the peal ply.

This is later placed in a homemade vacuum bag made from 4 mil plastic and sealed with latex caulking.

A piece of rope is on the far side of the wing.

Close the bag and turn on the pump. Mine shuts off about 6" of vacuum.

Allow to dry overnight.

RE: ViperDog Build Thread
 

After removing the wing from the bag you must trim the trailing edge.

RE: ViperDog Build Thread
 

Lightly sand with 220 grit paper on a sanding block.

RE: ViperDog Build Thread
 

The fabric used as the hinge adds a small amount of thickness.

I used some Spackle to level the area.

After dry you can sand as needed.

RE: ViperDog Build Thread
 

I marked out the ailerons on the bottom of the wing.

I cut about a 3/32" slot for the bottom gap.

RE: ViperDog Build Thread
 

Use a heavy duty set of aileron torque rods for this model.

Bend as needed to fit.

Sand the surface of the nylon tube to provide a surface for gluing.

Apply a drop of oil inside the tubes prior to gluing.

RE: ViperDog Build Thread
 

I mixed some Skin It and micro balloons for the adhesive.

Let this dry and later sand flush with the surface of the wing.

RE: ViperDog Build Thread
 

Since I am painting the wing the exposed foam in the gap needs to be treated with epoxy.

I used an acid brush to apply some Skin It epoxy.

RE: ViperDog Build Thread
 

Spackle was squeegeed to the surface of the wing to seal any potential pin holes.

The surface should be smooth and filled when finished.

RE: ViperDog Build Thread
 

The tail surfaces are cut out of 1/4" thick balsa sheet.

RE: ViperDog Build Thread
 

Strips of 1/64" thick plywood are glued into the leading and trailing edges.

RE: ViperDog Build Thread
 

The tail surface is shaped with a knife, razor plane, and sanding block.

RE: ViperDog Build Thread
 

The tail surface will have a full length gap-less hinge.

Tack the surface with a small amount of 3M 77 spray adhesive. I then laid a piece of window sheer on the surface.

Spray a little more 3M 77 and lay on fiberglass cloth. I used 2 ounce as the wood I used was a little too light (weak).

RE: ViperDog Build Thread
 

Mix about 0.75 ounces of Skin It and squeegee it to the tail surfaces.

Place the surfaces between 2 layers of peel ply (nylon fabric).

RE: ViperDog Build Thread
 

Place the parts in the homemade vacuum bag.

It is made from 4 mil plastic and is sealed with latex caulking.

RE: ViperDog Build Thread
 

After removing the tail surfaces need some trimming.

I used a sanding block.

RE: ViperDog Build Thread
 

A 3/32" wide slot is cut on the bottom of the tail surface.

I used a cut off disk to gradually remove the balsa without going through the top surface.