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BUILDER HINTS - LONG-EZ AND VariEze
Do not use peel ply over entire structure. This starves epoxy from lower foam surface, makes inspection difficult, gives an erroneous impression of good surface smoothness, makes it easy to unknowingly damage structure during finishing and adds weight. For example - if the elevators are peel-plied they will be too heavy to balance and must be discarded. Do peel ply surface edges of glass plys whenever they exist and, of course, whenever a lay-up will be later made over a cured surface.
Cockpit Paint - We have received a number of questions regarding ultraviolet protection of the glass structure inside the cockpit. Cockpit structure, like the external structure should never be exposed to direct sunlight without the protection of a suitable ultra violet barrier. A well-maintained coat of color paint is adequate, but it is desirable to use primer over the fiberglass surface. Dupont type 70S provides the best UV barrier (high content of carbon-black), however type 100S will result in better adhesion to enamel paints. Mike and Sally used a Standard Paints product, called "Zoletone", Charcoal gray in their cockpit. This material gives a beautiful speckle-type finish that hides minor irregularities and the glass cloth weave. This paint was sprayed directly on to the glass interior, after scuff sanding with no filling at 70 lbs. per square inch pressure.
Engine mount and mount extrusions - The older conical-type engine mount had tubes that were flexible enough to accommodate minor variances in the positioning of the aluminum angle extrusions in the fuselage. The new mount designed for the Lycoming dynafocal configuration has extra supports and is very rigid. Extreme care was taken to make the Brock welded mount accurate, to fit the extrusions, however normal tolerances may preclude a good fit on all airplanes. Thus, we are recommending the following method to assure an acceptable fit: Before allowing the extrusions to cure in place in the fuselage, clamp the welded mount to them. Shim with additional plies of BID if needed on the fuselage and center-section spar. Let the extrusions cure with the welded mount clamped In place.
Hot wire troughs - use the following method to separately cut the troughs. This gives more accurate, sharper cuts. Nail a temporary template (a Popsicle stick works fine) to guide the wire straight across over the trough. Then, remove the stick, and in a separate pass, cut the trough. Be careful to not let your core move between the cuts.
Drill a sight hole through all control push rods in order to verify that you have the rod ends screwed in with sufficient threads into the push rods. This hole should be 1/16" dia. located at 0.4" from the end of the push rod.
Page 9-3, Long-EZ plans, a small 1/8 o.d. brass tube 1/2" long is called out to be used in the end of the Nylaflow brake line. In some cases the little brass tube will slip up into the nylaflow tube, and be difficult to extract. This problem can easily be overcome by using a Weatherhead tube, part # 2030X4. This little tube has a flange on it and it works great. If you cannot obtain it locally, Aircraft Spruce has them.
Wiring the Rochester fuel pressure gauge.
Mike used Rochester gauges on his Long and they work well. The oil pressure and oil temp. gauges were straight forward to wire. However the fuel pressure gauge is a little different and some builders may not have received a wiring diagram.
We put a Marvel Shevler MA3-spa carburetor on N79RA without a primer system and since have accumulated over 350 hours on the airplane. The MA 3-spa carb has a built in accelerator pump which really makes starting the engine a lot easier, particularly in cold weather. If you plan on operating your 0-235 Lycoming In cold climates, an accelerator pump or primer should be considered almost mandatory.
After you have installed your ailerons, check to be sure you have minimum of 0.1 gap between the aileron leading edge and the bottom skin of the wing. This is necessary for protection from ice freezing the aileron to the wing. This can happen even in VMC conditions, if the wing is wet and you climb above the freezing level so do be certain to comply with this.
LongEZ builder hints.
Heavy Unidirectional Fiberglass Tape - The 3" wide roll of unidirectional glass is used only for the spar caps of the wing and center-section spar. "BID tapes called out are cut from BID cloth (generally 45" orientation). Other UND pieces or strips are cut from UND cloth. Be sure fiber orientation is correct.
The canard Inserts (page 10-2) should be drilled to match the hole pattern of CLT (page 103). These inserts (CLI) are available from Brock. Brock is also stocking the NG5 plate- (page 13-3}. Note: the raw materials list does not include the 1/8" aluminum for these parts.
Aft fuselage side shape. A number of builders have noted that the AS drawing has a different shape than that obtained when fabricating the fuselage sides per the page 51 dimensions. This approximately 0.2" error will not present a problem if you follow these instructions: carefully follow all the dimensions on page 5-1. This will assure that the firewall will fit. Do use the 5.8 and 6.9 dimensions on A5 and be sure the extrusions are perpendicular to the top longeron. Ignore the small difference between the bottom shape and that on AS.
Long-EZ Cowl and Canopy fitting.
As will be shown in the new Long-EZ Lycoming engine installation section (IlL), the Lycoming cowl has been moved aft 0.7 from where it was in a VariEze. This was done to provide better clearances. With the new dynafocal engine mount, the engine is moved aft also, to provide good magneto clearances and an acceptable structural arrangement for the mount tubes. The new Section IIL will show you how to fill the cowl-firewall gap when mounting the cowl using the method used on N79RA and on Mike and Sally's Long. Cowlings manufactured for Long-EZs after December 20 1980 have the lip extended to allow easier installation. These cowlings can be identified by checking the dimension shown below.
This cowling move has resulted in a miss-match of cowl-to-firewall at the top of about 0.2". Mike faired this miss-match in with dry micro, since he had already fabricated the canopy aft cover piece (Chapter 18). To avoid this micro fill, we suggest that you: trial-fit your cowling to the firewall before carving your canopy aft cover piece. If you have not cut out your firewall, make it taller at the top and trim to fit your cowl during Chapter 18. (see LPC #48).