| Home | Articles | CP reprints |
(From CP38, Page 4, October, 1983)
The following was sent in by Tom Williams. "One of these days, in the confusion that can happen when landing, one of us less than perfect pilots could hit that gear warning DEFEAT switch and then ignore the gear warning light (if you have one). Thats likely to ruin more than one day fixing your nose. I have designed an electronic circuit which will DEFEAT the DEFEAT in 60 seconds. The relay shown in the circuit is the same one shown in the plans. The timer chip and all of the other components are available at Radio Snack or just about any electronics supply store. The 60 seconds can be varied by changing the values but I believe you will find the 60 seconds just about perfect; longer might not give time enough to get your gear down on final and shorter will drive you up the wall in a long glide".
Click to enlarge
Make and fit all side consoles. Do not permanently install them yet. Make your plywood parts CS109 and CS118 and glue them to the side of the fuselage with 5 minute in the appropriate positions, using the side console for location. After the 5 minute cures, lay-up 1 ply of BID on each side of SC109 and SC118 (fore and aft) and lap onto the fuselage side at least 0.5". Allow to cure. Now make CS108 and CS118 (phenolic bearings) and bolt these into place. Install all of the pitch/roll control system from the front stick to aft of the firewall. Also install the fuel valve and all fuel lines. Also install conduits for electric wiring. Do all of this before the side consoles are finally epoxied and glassed into position.
Front Seat Bulkhead Location
For shorter pilots, Mike Melvill moved his front seat bulkhead forward 2". He did not change the angle or anything else. The landing brake is installed 2" forward of plans. In other words, it is still related to the front seat bulkhead per the plans. The landing brake handle position and right side stick controller were not changed. This resulted in an excellent fit for Mike(5 9" tall) and also for Sally (5 4" tall) and gave them a larger rear cockpit and helped the aft cg problem, since they used a starter and alternator. The landing brake, positioned 2" further forward, works great with zero pitch trim change.
Pitch Trim VariEze and Long-EZ
While most VariEzes and Long-EZs have a rather mild pitch trim change in rain, some are less mild than others. Try this: scuff sand your canard using 500 wet or dry (wet). Sand only in a chord wise direction, until you have a uniform dull look. Ken Clunis did this to his with surprisingly good results.
Shimmy Damper - VariEze and Long-EZ
If your nose wheel shimmy damper is not holding consistently, check to see if the phenolic "piston" is tight in its vertical hole. If so, ream the hole about .005" oversize to allow a nice free fit on the phenolic "piston". Reassemble, being certain to use the heavy duty spring called out in CP 30, page 4 and this problem should be solved.
Fuel Leaks into Outboard Wings VariEze and Long-EZ
We have now had reports from three different flyers that they have had small pin hole leaks in the outboard ribs of their fuel tanks, and that fuel had somehow seeped into the outboard wings. Small pin holes in the root rib of the outboard wings have allowed fuel to attack the styrofoam in the wings. This is a serious situation, since the wing structure requires the foam core for buckling support of the wing skins.
The solution of course, is to be positive that your fuel tanks do not leak and any fuel stains observed near the wing would require removal of that wing and careful checking for any loss of foam structure. Fuel will instantly melt styrofoam and will find its way through the smallest pin holes if its allowed to. If this happens, a repair requires removing all of the melted foam, and cutting back into good foam. Then a block of foam must be cut and fitted, then microed into this void. A possible alternative would be to use "pour-in-place" Liquid X foam or equivalent. Sand the foam to the original shape and do a standard fiberglass repair.
Carb Heat Muff
Aircraft Spruce sells an excellent little carb heat muff. A simple tube that can be slid onto the Brock exhaust system, right side, forward header and clamped in place with two worm gear clamps. Ken Clunis turned this in and it is easy to do and works great.
Cutting BID Tapes
Try rolling the 1310 cloth into a 1" diameter roll at 45º to the selvage edge, having previously carefully straightened the fibers. Now use a large sharp pair of shears to cut off 2" wide rolls. Presto! Your 2" wide tapes are ready to use and even rolled up for you.
Out here in the desert corrosion is not a problem. Some builders however, do live in highly corrosive environments. Rodie Rodewald is one. On the north shore of Oahu Island in Hawaii, where the biggest surf in the world breaks is where Rodie keeps his VariEze and Long-EZ. The air is literally heavy with salt spray all the time and Rodie has found exposed aluminum parts, not anodized, will corrode. He strongly recommends anodizing and insists that it is easy and fun to do. All you need:
1 gallon plastic jug cut off to make a bucket.
1 gallon of battery acid (H2S04) at a specific gravity of 1.10.
A lead plate a little larger than the parts to be anodized.
12 volt battery charger (6 amps is best). Pure, soft aluminum wire.
Trisodium phosphate (TSP) available at hardware stores, diluted .80 ounces per gallon of water.
Cleanliness is very important to success. He used wooden tongs and chop sticks to handle all parts after cleaning and proceeded in the following way:
Degrease all parts to be anodized.
Heat TSP to boiling, cool to just under boiling, immerse parts 3 minutes.
Water rinse avoiding touching the parts.
Positive lead to parts.
Negative lead to lead plate. Use the aluminum wire. A good contact is the secret to success.
Immerse in acid.
Gas bubbles evolving from the lead plate proves that anodizing is occurring.
Leave parts in the anodize process 25 to 30 minutes.
Boil parts for 10 minutes in tap water to seal the anodizing.
The only caution note is to be careful with the acid. It is not a strong acid, but acid is acid and can burn, therefore use personal protection of skin and clothing and in event of an acid spill, wash thoroughly in baking soda and water.
Spark Plugs for Hard Starting Engines - VariEze and Long-EZ
Bill Price, a VariEze flyer with over 450 hours on his VariEze reports that for 400 hours his engine was a real beast to start, particularly while hot. He switched to platinum plugs and reports that his engine is now pure pleasure to start, idles smoother and runs better. Platinum plugs are quite expensive, but last a long time. Mike Melvill had REM40E massive electrode plugs in his Long-EZ engine, an 0-235-L2C (as called for by Lycoming) and found that every 10 to 15 hours the bottom plugs would lead foul. Instead of platinum (which may have worked), Mike used Champions REM37BY (extended tip) and the problem disappeared. In fact, the plugs were not cleaned for 260 hours, with no problems.
Prop Damage VariEze and Long-EZ
Remember, flying a pusher airplane, anything that comes off the airplane might possibly go through the prop. This Includes cowling screws, loose pieces of safety wire, nuts and washers left loose in the cowling, even wrenches inadvertently left in cowling! Be careful! Be conscientious about working on your airplane. You are the qualified mechanic doing maintenance on the airplane and it is absolutely your responsibility to do the best work you can. A cowling screw or a fuel cap going through the prop, can cause sufficient damage to the wooden prop, that you may have to land and wait for a replacement prop.
Engine Alignment VariEze and LongEZ
The engine should be mounted with the crankshaft centerline right on B.L. 0 looking down at a plan view. There is no side to side offset. Looking at a side view, the engine is mounted with down thrust. That is to say, the prop flange is higher than the magneto end of the engine. Ideally this is a 2º angle. Plus or minus 1º will be okay. When you install your engine mount, do not assume that the four forward tubes are square and true. Clamp the mount to the aluminum extrusions and measure from the firewall back to the flanges (conical mount) or to the donuts (dynafocal) and do not drill in the mount until you have it positioned correctly.
Prop Bolts - VariEze and Long-EZ.
If you are using a standard Brock prop extension with threaded drive lugs and crush plate, and a prop that is approximately 3 3/4" thick at the hub, (Teds, B&T etc) you will need 6 prop bolts. AN6H-51A will work fine and are much cheaper than the AN76 prop bolts.
Worm Gear In Nose Gear Mechanism VariEze, Long-EZ and
If you buy the worm gear from Boston Gear, it will not be a solid gear, but will have holes in the hub area. This can still be used, but must have the holes filled first. We simply used flox. See sketch.
Click to enlarge
If you would prefer a solid gear as shown in the plans, the only source we are aware of is from Ken Brock Mfg. Brock also sells this gear for VariViggen builders, for the main gear retract mechanism.
Front Control Stick Long-EZ
Be certain that the lower bolt in the control stick can not catch on the rudder conduit at full left aileron deflection. Check this carefully before next flight. One builder had this occur in flight. He got quite a scare before he forced the stick right and tore the conduit off the fuselage side.
Sticking Fuel Valve - VariEze and Long-EZ
Hank Ashmore has found an excellent replacement for a VariEze/Long-EZ fuel valve. It is a Gerdes products fuel selector valve, and is found on Beech Musketeers Sundowners, Sierras etc. It is a perfect match for the EL valve and does not stick. Hank found his at an aircraft salvage yard and paid $20.00 for it. Unfortunately they cost around $125.00 new!! We are not advocating that everyone should run out and get one, but for those flyers with a particularly nasty sticking valve problem, it may be an alternative worth considering.
Corner Tapes - VariEze and Long-EZ
Installation of BID corner tapes, such as in corners between fuselage sides and bulkheads can be a time consuming job. Try this: spread out a piece of aluminum foil (such as Reynolds). Lay up the BID cloth, usually two plies, large enough to cut all the tapes you are going to need, onto the foil. Squeegee this lay-up out to a good lay-up. Now cut your 2" wide tapes out of this lay-up, cut through the glass and aluminum foil. Sand and paint a coat of epoxy onto the area to be layed up over, then with your fingers, bend the aluminum foil to form the "tape" into an angle to fit into the corner. Carefully position it and lightly squeegee or stipple it into place. Peel the aluminum foil off, stipple to eliminate any small air bubbles, peel ply the edges and presto, a perfect tape. Really works well.
Wing Fitting Ventilation - Long-EZ
The outboard main wing attach fitting recesses in the wings should be ventilated to avoid an accumulation of condensation. Drill a #30 hole in the bottom cover. Remove the top cover and drill a hole in the lowest point of the recess such that it will break into the recess underneath the wing. This hole should allow a soda straw to slip through. Work a little micro into this hole and slip a soda straw through. Allow to cure. Now carefully cut the soda straw flush with the bottom of the recess. Silicone the top cover back on. This will allow the two covered areas to "breathe" and eliminate condensation, which could corrode the wing bolts.
Click to enlarge