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Builder's notes:

• Scallop the back edges of the leading edge, otherwise the straight edges will actually bow upward, causing ugly bulges in the fabric covering. I used a pair of small, curved blade scissors - a sewing tool, I think. Whatever you use, be careful to avoid slipping with the tool and ramming into the side of a rib - I can't over-emphasize how susceptible they are to the application of force from the side!

• Discard immediately the banding material that comes with the kit for suspending/attaching the wing tanks in the root wing bays. It is ordinary, rustable, crate banding. Use stainless steel strips instead, difficult though they may be to obtain (we had to fabricate ours by cutting them from thin steel sheet stock). Use sewn felt sleeves to protect the tank and the banding where it passes over the tank edges (this is traditional practice). We modified the attach points from the plans so as not to put screws directly into the spar caps. We epoxied extra wood pieces (remember all the scraps you're keeping?) to the outside edges of the spar caps to give the banding more purchase in going over and around and under the attach block, then running a stainless steel bolt through the banding and attach block. Do it this way and you'll have no worries about the wing tank staying secured for the life of the aircraft. Remember, the tank will be enclosed by geodetic pieces (as seen in the next photograph) and the wing covered with fabric. Problems with the wing tanks would require a lot of tear-down to fix, starting with removal of the wing(s) from the aircraft - a real pain, I assure you.

• To further minimize the possibility of problems with the tanks after the wings have been skinned, pressure test the tanks before finally installing them in the wing root bays. See Tony Bengelis' chapter on fuel tanks for information on how to do this. The same goes for the main fuel tank in the fuselage.

• Plumbing the wing tanks. Do use finger screens (not supplied with the kit) in the wing tanks. Run aircraft-grade aluminum fuel tubing from the tank outlets to a miniature T-valve with shutoff which will fit nicely in the upper wing cutout area, then run a single aluminum fuel line the length of the upper cabane strut cross piece, then with a 30-degree or 45-degree fitting, turn and run it down one of the front cabane struts into the fuselage fuel tank bay. These lines can be safely secured with rubber-coated pinching clamps and nylon wire ties. Once inside the fuel tank bay, use a fitting that accommodates the flared tubing at one end and a rubber fuel hose fitting at the other. The rubber hose is necessary to make the turns necessitated by the narrow space between the the fuel tank and the firewall bulkhead. An extra hole is drilled into the front of the main fuel tank, near the top, and a fitting installed to accept the other end of the rubber hose. What this does is to enable you to simply re-fuel the main tank from the wing tanks simultaneously while in flight, and saves the trouble and plumbing connections needed to run all the tank fuel outlets into the switching valving needed to enable all tanks to separately feed the carburetor.

• Fuel tank caps: as supplied by Fisher Aero Corporation, the tank filler necks are threaded PVC pipe sections, and the caps are internally-threaded PVC pipe caps. The filler necks and caps should probably be replaced with commercially available standard necks and caps. The reason being that PVC thread against PVC threads tend to bind, making the caps sometimes nearly impossible to remove. We remedied the wing tank caps by using non-threaded PVC pipe caps, with a stainless steel bolt run down through the top and using a spring-loaded wall anchor toggle, in reverse, on the bolt so that you must hold the toggle wings down to insert them in the filler neck, but can simply pull the cap straight up from the filler neck when you need to remove them. They will hold during aircraft motion. Be sure to use double nylon lock nuts on the bolt, or drill the bolt end and use a cotter pin, to insure that the toggles don't spin themselves off during aircraft motion and drop into the fuel tank.

• We experienced a pressure drop across the top of the original wing tank caps in flight due to a hole in the top of the caps through which passed the wire/float fuel gauges. This kept us from being able to re-fuel the main tank from the wing tanks during flight. That has been remedied by drilling a whole forward in the cap and epoxying an aluminum ram-air tube of small diameter into the hole, to pressurize the fuel tanks in flight. To avoid installing the caps with the ram-air tube facing backward, the edge of the filler necks were notched, and a small pin inserted through the side of the caps in a position where the tube must face forward, and the pin must drop into the notch, for the cap to fit properly.