|Left Wing IV|
|Alum between wood...|
Tonight I fitted the aluminium trailing edge. I like Randy's suggestion of fitting a full length trailing edge in one long piece bridging the aileron at the same time, then cutting at the aileron/aileron well location after curing [guarantees a straight line]. However, my alum came from Steen and was already cut to rough length. I trimmed the T/E with a chop saw/TCT blade, sandwiched between two boards so as to avoid snatching.
The T/E was then glued on with T-88. I mixed some T-88 with talcum powder to form a paste [a bit like microballons I suppose], then applied a blob on each rib tib prior to pushing home the T/E. The reason for this is that there is a natural internal void where the tip of the rib locates and during the fabric process, the tension of the fabric can pull the T/E in a little - causing wrinkles. The paste forms a 'stop' to prevent that.
I had put a plumb line down the tails of the ribs to confirm lineage, but looking down the trailing edge, there was a very slight bow, so I used doubled up cable ties to add a little pressure while curing.
I then went to my trusty bargain bundle of spruce from ASS and milled down some 1/2 x 1/2 for the bracing and gussets and fitted those. Keeping that tail rib at st.57 1/4 square is important, because you don't want a taper in the 1/2" gap that will be between the aileron and that station.
Is it square?...
Cable ties are handy things...