Bambas Family Website

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May 24, 2016

Dolly and I built the horizontal and vertical stabilizers & the rudder and elevators (the empennage) during the winter of ’14/’15 in Florida.  The parts were wrapped in blankets, hauled to Michigan and have been sitting on a shelf waiting for today.

The entire process of mounting the empennage, adjusting balance weights and travel stops, installing and smoothing fiberglass tips and connecting controls lasted until July 1, 2016.  Other non-empennage tasks were also completed during this interval.

We were careful to align the HS with the fuselage, measuring from the tips to the same rivet position on each side.  Then, drill and bolt.

It was necessary to trim the rear outboard skins of the HS to allow clearance for the elevator balance arms.  The elevators were temporarily attached.  Then the elevator control arms were drilled for a center pivot and the push/pull control rod connections.

Dimensions:

The vertical stabilizer was mounted with it’s tip to elevator tip distance exactly 62 1/4 inches on both sides.

Elevator travel was measured as 25 deg. up and 27 deg. down.  Later, after adding stops and adjustment the final measurement was 28 deg. up and 21 deg. down.

When the rudder was installed with stops, it’s swing was set to exactly 35 deg. right and left.

May 27, 2016

Van’s plans call for trimming of the lead counterbalance weights that are installed in each elevator balance arm.  Our band-saw wouldn’t do it so I jury rigged a clamp and hand saw.  ~10.6 ounces of lead was removed.

The Right elevator balanced OK per Vans criteria, slightly elevator nose heavy.  Addition of the electric pitch trim servo overbalanced the left elevator tail heavy.  More weight ~2 oz. was put back into the left balance arm.

The above photo shows the pink slab foam, 0.17 lead shot pellets and a portion of the large lead weight epoxied into the left elevator balance arm.

After an initial layer of epoxy, both arms were leveled to the top of the aluminum with a micro-bead epoxy paste, and then sanded smooth.

As received, the Vans fiberglass tips did not align well.  These photos show how much epoxy/micro mix was added to the HS tip.  The pen lines outline the rudder area next to receive micro.

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While installing the rudder lower fiberglass tip, I also installed an AeroLEDs strobe tail light.  The strobe driver is fully contained in the tail light.  It will later be wired to synchronize with the wing strobes.

May 16, 2016

At the 2015 Sun-N-Fun expo in Florida I first saw a Beringer wheel on display. The wheel hubs (split case with Michelin tubeless tires) are machined on all surfaces from aluminum billets and then anodized to a brilliant red. They are as much jeweled works of art as functional devices.  I explored their website.  The prices turned me away.  However,  I read on the VAF forum that Beringer was for a while offering a 30% discount on full Vans RV systems to the first buyer from each  EAA Chapter.  That and the significant weight savings did it.

In addition to the wheels and master cylinders the displayed parts came in the box.

In the Beringer system the right and left brakes each have their own fluid reservoir.  I fabricated a tray to hold the reservoirs and hopefully direct any overfilled fluid to a safe collector.  I plan on adding a 5″x8″ inspection port to the fuselage top front skin for access to the area behind the instrument sub-panel and for viewing the reservoirs while the system is being filled.

The device to the right and below the reservoirs is the Beringer ALIR Anti-skid Inline Regulator.  It is adjustable and sets the maximum differential between the right and left brake line pressures.  At this point I was ready to assemble and install the cabin side brake lines.

The eight Teflon lined and stainless steel jacketed lines were wire-tied to the moving rudder pedal assembly.  The rudder and brake pedal movement were checked free and clear with no rubbing or binding of parts.

 

May 12, 2016

Our first task upon returning to Michigan from the instrument panel building winter in Florida was to fabricate a support plate and install the Andair fuel valve. This was followed by bending and routing the 3/8″ OD soft aluminum fuel lines in from the wing roots to the valve.

A  coiled spring type tubing bender was found to be much more useful than a lever type bender.  Rubber grommets protect the lines where they pass through the fuselage skin.  The free floating  grommets will be placed in the spar forward cover plates.

Fuel vent lines were added for each tank. They enter the fuselage sides, travel up to the top longerons, forward to the firewall and down through the fuselage floor. Cut at a forward facing 45deg. angle the vents tubes apply a small positive pressure to the tanks. A cover screen prevents entry of large bugs. The left vent tube fuselage floor exit can be seen below.