Elevators levelled and riveted

Tail not levelHaving removed the elevators to allow the tail to be rigged it is an opportunity to place them on a flat surcae and drill the centre connecting horns through once the LEFT and RIGHT have been levelled with each other AND the elevator horn has been set to the required 60 degree rake forward.

This would have been pretty hard to do whilst they were fitted to the aircraft due to incidence on tailplane and all bits generally getting in the way .. so much easier laid flat on the floor with a large spirit level
tail level

HIGHLIGHT – Elevator Intermediate Horn connected

Finally got around to working out the bushing and support for nthe rear intermediate elevator horn. A small 1/4″ washer is filed to provide an ‘internal’ facing chamfered edge to but against the industrial ball swivel. This allows the ball head a greater degree of movement rather than coming up agsinst the albeit very smaquare edge of a 1mm thin washer.

This meant I could trim the trailing intermediate rod – that is connected inside the torque tube to the rear (Pilot) joystick.  Once measured and checked 5 times in situ (DO NOT want to cut this one wrong !) then the whole torue tube, control joysticks and training connecting rod are removed from the aircraft to allow drilling and riveting of the end connector. Tube had all been pre coated internally with Waxoyl to prevent any internal rusting.

Once drilled and riveted the whole lot can go back in the ‘plane and a trial connection to the elevator intermediate horn..

 

FANTASTIC to see a stick pulled back move both sticks in unison (obviously !) and then the elevator horn move through the pre requisite angle and no catching ….

Just the cables now to the rear elevator horn .. remember they have turnbuckles AND crossover towards the tail to make sure Back on the stick equals UP elevator !!

Aileron leading edge support block

Blasa  blocks are provided to be trimmed and cut to fit between the ribs – mounted on top of the spar (using epoxy) to then be shaped to form a mounting surface for the top leading edge 0.8mm ply

The blocks are first pre shaped to provide a ‘mated’ key to the top of the spar. A 1″ round dolly is used with sandpaper wrapped around to provide a suitable curved channel in the bottom of the balsa block.

 

Once dried these can then be shaped on top using a larger hardwood dolly to overlay two ribs so that you sand down evenly to get a flat surface.

The 0.8mm ply is then epoxied to the top if the block and, once dry, Aerolite glue is used to secure to the top of the ribs and the leading edge beech.

Aileron – Firbeglassing ribs in position

Not a job I had looked forward to … hate fibreglassing at the best of times … not nice stuff to work with !

Cut 20 mm wide strips by 60mm of 600g (2 oz) mat (CSM) and this makes it more manageable when trying to get it over and around the compound curve of the aileron spar. These strips were overlaid but still managed to ping up occasionally in the drying process !

The small pointed sander came in handy to neaten  off  the usual spikes of strand that you get with this process … how anyone ever constructs major pieces with this stuff is beyond me

The finished sanded joints dont look too bad and have ceratainly made the whole thing feel very robust.

Aileron – Leading edge – Scarfe joint

The leading edge ply for the aileron leading edge is 0.8mm so quite plyable … only problem is that it is just too short for the length of the quite large ailerons … this means making a scarfe joint to butt two pieces of ply together to make up the length.

 

Having read up on the internet exactly what a scarfe joint is … basically a layered joint to ‘blend’ one piece over the other. The internet was useful in that it gave advice on how your new joint was squared up … ie sanding using a hard block on the edge of a solid surface … then checking that the various layers (3 in this case) reveal in a straight line … then you know your chamfer is square

 

First Inspection

Been getting the plane and workshop ready for the first inspection. All the relevant build digrams have been stuck to the airframe in the proper place to make checking easier.

Fingers crossed as I cant continue with other cabling and top deck bits until that is approved.

Preparation for Rigging

To prepare for the tail rigging I need to remove the rudder

and then the Elevators

This gave me a chance to complete the Elevator horn alignment – angles on a 60 degree forward rake to pick up the cables from the intermediate elevator forn mounted under the pilots seat.

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