Covering The Fuselage
Poly Fiber Method
The following is a Poly Fiber covering job of the fuselage. We will also present an AFS method covering job in another web page. Please remember, there are usually several ways to complete any job, the following information is just one of these examples.
In this build, the builder installed a heater box. However, although you will notice this in some of the photos, we will not be covering this installation in this build section.
Prior to taping, it is recommended to first use either a plastic mallet or square head "shop hammer" type to tap down any sharp aluminum edges as close to the aluminum tubing as possible. This should be done on "ALL" fuselage side ribs and sheet aluminum edges throughout the fuselage. This will help prevent the long term chances of the aluminum edges cutting or wearing through the covering or skin of the plane after the plane is flying. |
When getting ready to apply your glue, it is best to use an inexpensive masking tape to create a "straight" glue edge along the surface of the tubing. This will not be needed where you will be gluing and wrapping the fabric "around" the inside of the tubing surface. This will improve the final look of all glues seams. |
Before applying the glue edge tape, be sure to completely clean all aluminum parts and tubing to be glued with MEK. See MEK Warning Information before using. |
There are two primary types of gluing systems, Poly Fiber's and AFS. This builder will be using the Poly Fiber system, using Poly Tak glue. |
Be sure to lightly sand off any corrosion with 400 grit sandpaper (NOT steal wool) and clean all aluminum tubing with MEK before taping off and applying any glue. Apply about a 2" glue area on the edge of the nose cone. After taping off for any glue lines, apply two coats of Poly Tak glue with a 1" to 1-1/2" paintbrush, allowing each layer to dry between applications. The builder forgot to take a couple photos, so you will have to use your imagination on the bottom covering. |
You will need to reactivate the Poly Tak glue below the fabric by applying MEK with a small paintbrush in about 6" to 10" long strips. Use your fingers to rub the MEK down through the fabric to pull the Poly Tak glue up into the fabric. You should notice as the MEK dries, you will feel the Poly Tak glue in the material. Start tacking the material to the cage at the front of the fuselage from side to side and work your way to the tail. |
Once you have the bottom fabric fully tacked down, you can now trim off any excess material, and finish gluing the material to the aluminum tubing by reactivating the glue with MEK. |
Poly Brush is not only a pinkish color fabric coating to seal the fabric prior to painting, but it is also a "GLUE" and will be used anywhere you are joining fabric to fabric where an aluminum tube is not below the fabric. In these areas, you will not use Poly Tak glue. Only use Poly Tak glue where an aluminum tube is below the fabric. There are two pieces of fabric per side of the fuselage. You will attach the larger of the two first, which extends from about the middle of the two place door opening to the rear of the tail. The second piece is much smaller and is attached from mid-door opening to the nose cone or over the fuselage nose, if... you are not installing a fiberglass nose cone. For the first side, you will need to apply the glue edge masking tape to the aluminum tubing just above the fabric contact point and around the tubing. This will be for use with Poly Tak glue. However, applying Poly Brush to the bottom fabric edge will be a little different. Apply your glue edge masking tape about 1-1/2 inches from the bottom aluminum framework onto the bottom fabric as you will be gluing the side fabric directly to the bottom fabric using Poly Brush, not Poly Tak glue. Apply two coats of Poly Brush to the bottom fabric edge 1-1/2" area prior to covering, letting each coat dry completely between coats. |
Using spring clamps to hold the fabric in place, start at the top of the fuselage. Reactivate the Poly Tak glue on the tubing working down the down tubes at the firewall and rear compartment until you reach the bottom of the engine firewall area. Now, carefully smooth out the fabric as much as possible to firm and glue the fabric down to the 90 & 45 degree tubes to the rear of the engine area. This area is the most difficult section as you need to make sure you do not cause any large pulls or wrinkles in the fabric. (THIS IS IMPORTANT) Now, gently pull and smooth out the fabric and finish attaching the fabric to the rear cabin down tube.
Work along the tail's top rail aluminum tube and longeron at the same time, attaching the fabric as you go. First tack about 10 inches at a time to the top tube with glue, then to the bottom longeron with MEK to draw the glue to top surface. Attach and trim the fabric as you go to the cover/glue plates at the end of the tail. You can now attach the fabric to the cabin side rails, as well. |
Apply two coats of Poly Brush on the fabric which is on the bottom of the seam, then a wet coat to lay the top seam edge onto. Then brush more Poly Brush onto the seam surface to make sure the Poly Brush is thoroughly soaked through the fabric. Allow to dry, then wet again with Poly Brush and apply a strip of bias tape over the seam, also applying Poly Brush to the tape to make sure the Poly Brush is worked through the tape to the fabric. |
After ironing the side at 350°F, you need to go back over all the seams, also at 350°F to take out or flatten any wrinkles in any of the seams. This includes both the Poly Tak and Poly Brush seams. Once this is done, use Poly Brush to apply a 2" bias tape to the seam edge of the bottom fabric Poly Brush seam, making sure the Poly Brush is thoroughly worked through the bias tape. After the tape is fully dried, iron it down at about 250°F to 275°F. |
Now, repeat the steps above for covering the other side of the fuselage. |
It's now time to start considering how you plan on painting your covered fuselage, but that will come later in another building web page in this section of the site. |