Jan 21, 2024     Starting on wing ribs - (7 hours)       Category: Wings

Starting on the structure of the wing. I was able to find a vendor on Ebay selling 7/8" sheets of honeycomb aluminum panels. I purchased 7 panels, planning on making 4 ribs per panel. I took a page from my full sized plans and cut out the wing profile, and glued it to a piece of thin plywood. Sanding the edges, I created a drawing and size template. I got out my table saw, and cut my panels down to 7.5 inch wide strips. Using my template I drew the wing profile on each of my strips and using my bandsaw , cut them to rough size. A few minutes work on the belt/disc sander and I have a rib. Only 27 more to go!

  Nov 07, 2019     More Wings - (2 hours) Category: Wings

Spent the afternoon studying the plans and cutting down the rest of my wing ribs. For those that don't know, the BD-4 had a unique wing building technique. A tubular spar was carried through the cabin, and 10 feet out each side. Wing buckets were then slid over the spar, glued together and secured to the wing. These formed the fuel tanks when sealed, and the structure of the wings. Unfortunately, as all wing tanks will do, leaks occurred. This created problems as you might imagine. It was discovered that the wing tank sealant was very effective as long as it was kept wet by the fuel it was sealing in. If it was allowed to dry due to low fuel levels, maintenance, inactivity-leaks would occur. The BD-4 factory answer is to use aluminum honeycomb panels, cut to shape as wing ribs, slide these over the spar, glue into place, and to wrap aluminum sheet to create the airfoil shape. The aluminum sheet is adhered to the honeycomb panels with Pro-seal. This also serves to seal the bays that are used for fuel. The honeycomb panels are expensive, and I already had perfectly formed ribs available to me. My plan is to use the cut down panels as wing ribs, adhere them to the spar, then wrap the wing and adhere it to the ribs with pro-seal. The rest of the wing will be built to plan.

  Oct 06, 2019     Cutting down Wing Panels to make Ribs - (2.0 hours)       Category: Wings

I have been thinking for a long time on how to maximize my usage of the materials I obtained with my purchase of the uncompleted BD-4 kit. So, today I made a decision regarding the wing ""Buckets"" and how I would use them. I want to build metal wings, because I did not want to rely on the buckets to maintain the airfoil shape or hold fuel on an ongoing basis. BD-4's are famous for their leaking wings, and I was wanting to avoid this sort of infamy.

I decided to build a hybrid wing. I will use the wing buckets as the rib, cutting off the panel parts. I will secure the remaining rib to the spar, sealing it as called for in the plans. I will then place aluminum skin over wing ribs, using Pro-seal to adhere them as in the current plans. This will yield a very strong and light wing, and will hold the required 50 gallons of fuel and remain leak free. Later entries will describe sealing the wing tanks and using Pro-seal to make them leak free.