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R-80 Tiger Moth – A Wing, Part 1

 

 Now confronted with stacks of completed ribs, stacks of completed spars and stacks of completed laminated wingtip bows and curved trailing edges, there seemed nothing for it but to build a wing. The Tiger Moth has two sorts of wing: upper and lower (duh). Not so “duh” however, as the lower wings contain ailerons and the upper wings do not. Ailerons increase the size of the job by a fair margin. In any event, in best bullet-biting mode, I elected to start with a lower wing to get all of the learning curves out of the way at the outset.

The Tiger Moth wing is built by threading completed ribs onto the main and rear spars, supporting a notched trailing edge timber on an angled straight piece of 2’x 4’, getting everything squared and true and then starting to glue things together. After the wing-to-be is loosely assembled and made as true as possible, the rib tails are glued into the notches in the trailing edge (now nailed and clamped to the supporting 2’x 4’).

 Each rib has vertical pieces built into it against which the main spar is to rest and similar pieces for the rear spar. After the tails of the ribs are solidly glued to the trailing edge, The main spar can be glued to the appropriate vertical members of all the ribs. All the ribs are glued except the root rib.

 

 After that, the rear spar can be glued in place in the same way. Once both spars are glued to the ribs, compression struts are built in place between the spars. The compression struts consist of a web and two cap strips. There are four compression struts in each wing.