Builders Hints
April 1979
When you cut BID (Bidirectional)or UND (Unidirectional) fibergalss, mark the cloth where it will cross the center line with a fine felt marker. This mark can be very helpful in perfectly aligning such lay-ups as canard spar caps, etc. Draw lines (broad felt tip marker) on your glass cut-out table at 45 degrees to the sides on 6" centers. This is a big help when cutting BID. Be careful when storing foam blocks, not only can sunlight ruin it but rats and mice love to dig tunnels in it!
Finding fuel tank leaks. Purchase a can of Freon from your friendly auto air conditioner repairman, and borrow his Halogen gas sniffer. (This may require some persuasion!). Squirt some Freon into the offending tank, replace the cap, and pressurize the tank, (blow into the vent) Use the sniffer to locate the leak or leaks, mark them carefully and repair per CP #14 pg 10. This method will find even the tiniest pin hole leaks.
Check your main gear toe-in. This can really effect the life of main tires. See the accompanying sketch, and clamp or hold one 36" long straight edge on the outside of each main wheel , be sure it touches the rim both fore and aft of the axle. Position of the straight edges fore and aft is not important, as long as they are the same. Measure accurately the distance between the ends of the straight edges at ‘A’ and at ‘B’ . For 1/2 degree to 1/4 degree of toe-in per wheel. A-B=0.3 to 0.7"
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An excellent cowling idea from Herb Sanders.... Instead of gluing your cowling rib to the bottom cowl, glue it to the main wing root. This allows you to better fair the cowling in with the wings, and makes it simpler to remove the cowl, as either the bottom or top cowl can be removed independently of each other without hitting rudder cable or aileron tube. This requires four more Camlocs (or screws) on each side in the bottom cowl. The only time this would not be convenient would be for the builder who intends to trailer his EZ to and from the airport, requiring frequent wing removal. We have modified N4EZ to this configuration to test the Jiran Kevlar cowl and are very pleased with it.
Jim Eggleston wired up his instrument panel before installing it in the fuselage. He then bound all the wiring into a harness, color coding the wires and tagging each wire. The harness was then removed and the panel installed. Jim also reports that he used dead soft .016 aluminum, called handyman’s metal, obtainable at the hardware department of Montgomery Ward’s in rolls, to make his hotwire templates. This material can be cut to size (after paper templates are glued on) with ordinary scissors.
Before floxing VECS3 hinges into your canard, Bondo small wood blocks adjacent to the VECS3’s and overhanging the slots cut in the canard. VECS3’s can now be clamped to these blocks, templates can be removed from under the elevators, and the elevator travel can be checked before final potting in flox. Leave clamped until set. This tip from Minnesota’s EAA Chapter 587.
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When countersinking difficult to reach holes, e.g. 3/26’ dia. holes in engine mount extrusions, a 9’ long piece of 5.16’ dia. x .035 wall aluminum tube can be used. Drill and tap a x 28 thread in one end and screw in a 100 degree countersink with a 3/16" pilot.
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Many builders have requested a summary of weights of each individual part. These are weigh of the parts before any finishing.
Complete wing/winglet aileron assembly 43 lb
Above, after finishing 46 lb
Winglet before cutout for rudder 2.6 lb
Canard (142") 16.5 lb
Elevator (left) 3.6 lb with balance weights
Elevator (right) 3.3 lb with balance weights
Wings (each) 34.0 lb
Ailerons 3.5 lb
Center Section Spar 21.0 lb
Fuselage (at end of chap. #12) 65.0 lb including C/S spar
Canopy (end of chap#22) 14.5 lb
When cutting out small BID circles, as in bolt hole reinforcement in NG30’s, fold up BID cloth strips to required number of plies (30) and clamp between two scrap pieces of 1/4" plywood (firewall material). Vice grips work best. Now cut through plywood and glass with fine tooth coping saw or band saw. Presto perfect circles of BID!
Gear and canopy warning - this system has a resetting defeat feature. The main advantage is the ability to silence the horn, while doing gear-up, slow flight or descents. The light stays on as long as the throttle is retarded. Each time you cycle the throttle the horn will sound and will have to be re-silenced. This eliminates the possibility of switching the warning system off during gear-up descents, and forgetting to re-arm it for the landing approach.
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