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Q1 Plans Chapter 3 Page 3-22

Cutting the UNI Spar Caps

The spar caps used in the main wing and the canard are strips of UNI cloth that you will cut from the roll provided in the kit.

Begin by unrolling the roll on a long, flat surface. The example to be used here will be a spar cap that is 8” wide by 50” long. You would measure a 8-1/4” wide piece (to allow for frazzling of the edges) by 5O” long, with the fiber orientation running along the 50” edge.


Quickie Cutting UNI Spar Caps

The technique is one of finding the one strand that is at the edge of the 8-1/4” width, cutting it, and then pulling that whole strand the length of the spar cap to remove it. You will now see a clearly visible gap in the UNI cloth where that one strand used to be. Now, using an exacto knife or razor blade, cut all of the cross fibers along that gap, thus severing the spar cap from the rest of the roll.

Carefully mark the cap with a centerline(in this case at the 25” point) and roll it up to keep dirt out of the fibers.

When you next unroll it, you will probably find that the edges are frazzled. As long as you don’t reduce the width below the original callout(in this case 8”) you may pull off strands that are frazzled. Be carefull to only pull loose one strand at a time or else the whole spar cap will start coming apart

Glass-to-Glass

In order to improve the rigidity of a part, you will occasionally be asked to perform a glass-to-glass layup, sometimes abreviated as GTG.


Quickie Glass-to-Glass Layup

The example shown here is a glass-to-glass layup on a bulkhead. Begin by glassing one side of the bulkhead as usual. Next, having turned the bulkhead over after curing to prepare the other side for glassing, you will remove foam with a smooth transition so that your next layup will butt up against the previous glass layup.

The amount of “overlap" necessary varies with the loads. On bulkheads, use a minimum of 3/8”; on the trailing edges of ailerons and elevators use 1/4” minimum, and on the trailing edges of the wing, use 3/8” minimum.

"Tapes"

Quite often during the construction of your Quickie, you will be asked to use glass tapes to join to pieces together.


Quickie Glass Tapes

A glass tape is a strip of BID cut at 45 deg which is used to lap up onto both surfaces that are being joined. For proper strength, the tape should be at least 2” wide.

Phenolic

Before bonding phenolic to any surface, be sure to sand the phenolic dull(i.e. to remove the shiny surface) immediately prior to doing the layup. This avoids getting grease from your hands, etc. in the layup, whch might cause poor adhesion and subsequent failure of the layup.

Q1 Plans Chapter 3 Page 3-23

Education Supplement

Rip this page out of your plans and staple it to the wall of your shop. While it is a handy reference, it's still a good idea to read all the words in the eductaion chapter once in a while. Don't skip the details - they're all important.


Quickie Educational Cartoons

URETHANE FOAM SHAPING

BASIC TOOLS: Sharp butcher knife, sanding block, surfoam file, wire brush and blocks/scraps of urethane. Use a dust mask. Hack away. Have Fun.

HOT WIRE CUTTING STYROFOAM

Hot wire tool has two lengths: 62" and 43"

Wire must be tight. The adjustable voltage control is best, but the job can be done with 2 12-volt, 6-amp battery chargers or a 12-volt car battery. Foam block must be well supported and weighted. Templates must be nailed on tight. First cut the basic block to size: this determines the planform size and shape. Level the template level lines: this determines correct twist. Set hot wire temperature for about 1" travel through the foam in about 4 to 6 seconds with light pressure. Do the actual cutting at about 1" every 6-7 sec. (8-10 sec. around the leading edge. Practice on scraps first.


Quickie Hot Wiring Styrofoam Cartoon

BASIC LAYUP PROCEDURE

1. PREPARATION: Ply 9 or gloves on hands, shop temperature 75° ±10°

2. CLOTH CUTTING: You can get by with just a standard pair of good fabric scissors, but the job is much easier with the large pair of industrial scissors. (Weiss model 20W). They're $20 (gulp!) but worth it in the long run.

3. SURFACE PREPARATION: Foam - Hot-wire-cut surface needs no preparation. Sand ledges or bumps even, fill holes or gouges with dry micro immediately before the layup. Brush or blow away dust.
Glass - Always sand completely dull any cured glass surface (36-grit or 60-grit sandpaper). Resand if it has been touched with greasy fingers.
Metal - Dull with 220-grit sandpaper.

4. MIX EPOXY: Follow all mixing steps shown on your epoxy balance. Mix two minutes, 80% mixing, and 20% scraping the sides and bottom. Don't mix with a brush.
:Micro Slurry - Approx equal volumes of mixed epoxy and microsperes.
:Wet Micro - Enough microspheres for a "thick honey" mix.
:Dry Micro - enough micro so it won't run
:Wet Flox - Thick, but pourable mixture of epoxy and flocked cotton

APPLY TO SURFACE:
Layup over Foam - Brush or squeegee on a thin micro slurry layer (Thick over urethane)
Layup over Glass - Brush on a coat of epoxy.

5. LAY ON CLOTH: Pull edges to straighten wrinkles. If working alone on a long piece, roll the cloth, then unroll it onto the surface.

6. WET OUT: Don't slop on excess resin; bring epoxy up from below with a vertical "stab" of the brush ("stippling"). Start in the center and work out to the sides. Most of the time of a layup is spent stippling. Stipple resin up from below or if required, down from above. "NOT WET, NOT WHITE>"

7. SQUEEGEE: If you have excess resin, squeegee it off to the side. Use Squeegee with many light passes to move epoxy from wet areas to dry areas.

8. PRELIMINARY CONTOUR FILL: Save sanding by troweling dry micro over low areas while the glass layup is still tacky. This is done at trailing edges, spar caps, or over any low areas. The low places are over filled with micro then sanded smooth after full cure.

9. KNIFE TRIM: Save work of sawing and sanding edges by razor trimming the edges at the "knife trim stage" which is about 3-4 hours after the layup.

10. GENERAL INSPECTION: Take a good look for dry glass, excess resin, bubbles, and delamination before walking away from your wet layup.

11. CLEANUP: If you've used Ply 9 skin barrier, you can get all epoxy off your hands with soap and water. Epocleanse is also excellent for for removing epoxy and it returns natural skin oils. Brishes - rinse twice in MEK and wash with soap and water. Throw away after two to four uses.


Quickie Basic Layup Procedure Cartoons



 

Quickie Hardware Sketches


MINIMUM RADIUS FOR GLASSING OUTSIDE CORNERS

Minimum Radius For Glassing Outside Corners


QUALITY CONTROL CRITERIA/REPAIRS
See the Eductaion section