Harrier build notes

 

  It's exciting to be at the start of a model's life, I thought it might be useful if I started to make some notes on the Harrier build.  The general construction goes along the same lines as the Willow 2 and SOR models.  There have been several improvements in model construction and design- speeding up the build and progressing the final model.

Wings

  The wing assembly is very straight forward.  The horns are supplied separately and these are glued into the wings, This gives you the opportunity to fit the horns and clevis’s flush to the wing skins.  I have used 2 and 3mm clevises for this in the past- they all work very well. There is enough room to fit the drive system of your choice, I know that I am getting old in my build techniques.  

  It is likely that you will need to grind some of the clevis off to help it move freely- this is normal.  When you order your model you can ask Zhou not to glue the horn in t the wing, I prefer this.  Once the servos and horns are in place.  Measure the distance so that the push rods are made up to the correct length.



  The holes in the wing for servos have are large enough to help fit ball-raced servos frames.  I’ve been using King Max servos and their frames.  The fit in the Harrier is excellent and the servos have proved to be fast, reliable and slop free, for the money I’m really happy with the servos.

 

Fuselage

  The Harrier fuselage assembly has been made very straight forward thanks to the moulded tray.  This fits the servos, switch and ballast tube.  As it does not arrive fixed, making the cuts for the fittings is very simple and safe away from the rest of the fuselage.  it also makes threading those servo wires much more straight forward.


  The Ballast tube will slide in place once the servo tray is fixed.  I glue this in place using epoxy and chopped mat.  I have found that I need to make a hole for the lock nut to recess into.  A final and possible over kill is to fit a block of wood between the ballast tube and top of the fuselage.

  Like all the models I have worked on with Zhou, the ballast tube takes 19mm chrome shower rail perfectly.  The fuselage ballast tube takes over 1.2kg of lead and has always been more than enough for me!

  The back of the fuselage is fully enclosed.  Before starting to fit the tail, the 5mm carbon rods need to be fitted and fixed.  The easiest way to do this is to drill through the fuselage so that the 5mm rods span the rear of the fuselage, this is the recommended way and the strongest.  This makes for an excellent tail fix as well as adding further strength to the fuselage.

   Be careful not to snag the push rods with the 5mm tail joiner.  It should slide by nicely when everything is together but taking the rods out to have another go after you have glued them in is not easy.

  The tails come without the elevator horns fitted. To give you the choice of how you want to do it.  My recommended way is to use a piece of 2mm push rod (about 10cm long).  Bend the end as shown as this gives a mechanical link to the elevator sub spar.


   Bend and tape the elevator open enough to expose the inside.  You will be able to see the sub spar.  Make a hole in the sub spar and at the root of the elevator to let the elevator horn through.  Measure up to make sure that there enough rod coming out to make an elevator horn and insert the rod into the sub spar.  Some epoxy and micro balloons dribbled in to the elevator will fix the horn in place nicely.

  The connectors for the clevis are made from brass tube.  Flatten 1 end and make a hole for the clevis you are planning to use (1.5mm works for a 2mm clevis).



   You can see where a slot has to be cut in the fuselage to allow the push rods into the fuselage.

 

 The back of the Harrier is a tight fit but full size clevises can fit. You can see where I opened up the back of the fuselage slightly for the clevises to move more freely.  This helps you to make the the copper rods a little longer and help the elevator gearing on you servos.

   The copper tubes are first glued and then crimped onto the steel rods.



Settings

  These are still a work in progress and I will change them as I learn.  Especially with the aileron movement, these can be cranked up for faster response with no danger in flight.

                Aileron up 20mm down 12mm (at root) Flaps up 3mm down 2mm

                Flaps for breaks, over 45deg down slops her nicely

                Snap flap down 2mm across the wing

                Elevator up/down 6/7mm measured at the root.25% rudder mix is a help

 

CG 100mm

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