Big moments !!
The lower wings – apart from polyurethane (planned for this weekend) are now ready for final alignment and fit.
The trusty old trestles now have to be re-jigged and set to take the weight of not only the bottom wings but the interplane struts and then the top wing in preparation for the rigging.
The first thing was to level the fuselage fore and aft and laterally. This took some doing as an old barn is hardly likely to be level. Having opted to not remove the engine – the aircraft is trestle at the rear and has a large painted breeze block tied securely in to stop her tipping on the nose. That gets fore and aft sorted. The lateral was a little trickier and took some packing under the starboard wheel to settle her nice and level.
A chunky (not flexing) dihedral board has been made up and needs to be long enough to span 3 ribs to ensure you get a measured / accurate slope. With a 3 degree slope cut in the bottom – and placed the CORRECT ! way around, a spirit level on top should read zero.
The main wing trestles (two each side) have been really useful whilst working on the wings but now need beefing up as well as packing up to take up the gap now in place with the 3 degree dihedral.
The trestles have now not only had packing but vertical support posts to ensure no flexing takes place.
By doing this to all 4 trestles you get a very robust platform from which to work.
The plan guidance advises locating the supports very close to the point at which the strut supports locate – a busy area on the wing as this is where the aileron bellcrank is.
Leave a Reply