Building instructions for your Minij
The Minij is an all composite model with multiple uses. Slope soaring, ridge soaring, hand launch, high start and even for some major speed sessions with the optional MH22 60 inch wing available from Aeromod. (If you follow the measurements given, this wing will fit without any additional adjustments, allowing you to have 2 planes). In order to capitalize on all these aspects of the aircraft, we urge you to take care and follow the instructions to the tee. All control surfaces must be free from any type of play.
This glider is very manoevrable and this without losing performance. We recommend that during the servo installation process, you take into consideration the ballasting of the model, as this will make many a happy moment when the conditions are preferable. For this reason, trial fit your ballast tube along with your servos.
The glider has been painted in the mould and once again, no white spirits or alcohols must be used to clean it up. Rather use masking tape during the building sequences.
Choice of version
You may choose to use this as a low wind/low wing load plane or a full 4 axis flyer, once again the choice is yours and the basic building guidelines will be explained hereunder.
This being the lightest of the 3 versions, allowing you to benefit from marginal lift and wind conditions. Good thermal version off a high start or a winch. The absence of the rudder makes it a little more difficult to follow those thermals around. This version also has the advantage of allowing the user to install a 2-4 channel non programmable radio. 2 standard servos can be used to save on costs but the object of weight gain would be defeated.
As described above, this version is ideal for thermal catching as the rudder allows for tighter control during flight. Aerobatics also become a little crisper. If you wish to use a non programmable radio, you can make your cruciform stab, although the v-tail is more efficient. For this version, 3 micro servos are required.
Aileron/elevator/rudder/flap - 4 Axis
This is what all Aeromod models were designed for, and this is what we highly recommend. 4 servos are required for this version but the results will blow your mind. This allows for a plane that can adapt itself to any given situation by the simple use of camber on the flaperon. These serve both as flap and airbrakes and can be made adjustable during different phases of your flight. Enclosed in the CD rom of this plane are elaborate notes on 4 axis flying. You do however need a programmable radio for this version.
This project should take you between 6 – 10 hours to complete.
Wingspan : 1500 mm
Cords : 180, 140, 70mm
Wing area : 23 dm2
Profile : Selig 4083 modified to 6.5%
Length : 820 mm
All up weight : 450 g à 550
Ballast weight : 250 g
Wing loading : 19 à 24g/dm2
with ballast : 32g/dm²
The ailerons are 5.4cm wide ( 30% of the chord ) at the root, and 4.2 cm at exactly 130mm from the tip. These are marked out during the moulding process and can be eyeballed on the wing surface.
In order tu cut out the ailerons, I prefer to use a hacksaw to cut into the depth of the wing. The thickness of the blade allows for a gap wide enough for spacing once we hinge. Using double sided tape, glue a metal ruler along the top of the wing and pass as many as 8 times, each time applying a little more pressure. Do not allow the blade to cut through the foam but rather allow it half way. The reason for this is that we need to cut the bottom of the wing approx 3mm ahead of the top cut. This allows for an angle to form and allows downward movement of the aileron once hinged. As for the top, tape your ruler and allow yourself a few passes before applying the pressure.
Ball link installation
The ball links are used for quick and easy rigging of the wing, as well as slop free movements. My preferred method is to make a 10mm circular cutout from the bottom of the wing up until the top skin, without going through it. I then place a mixture of epoxy and micro balloons as a filler. Once dried I drill a 2mm hole right through the wing in the centre of this circle and glue my ball link in place. The distance from the bottom of the wing skin to the ball link should be approx 6mm.
The wing is attached by 2 x 4mm nylon bolts. Their length will vary according to your internal setup but should be a minimum of 18mm. Drill 2 x 4mm holes in the wing, the first 2cn from the L.E, the second 10 cm from the L.E. Don’t worry, the centre of the fus has been reinforced and can handle the load. If you wish to countersink your bolt, hand drill a 6mm hole on the top of the wing, not exceeding 3mm in depth.
Should you have the 2 pce wing option, using a 4mm round file, measure the listed distances from the L.E and file the half holes in each wing half. When you will eventually fly this plane, all you ddo is join the wing with the carbon joiner and tape the wing together on the join with electrical tape. This is quite enough to hold the wing together.
Sanding the stab as per the picture below, round off the L.E and allow for an angle of 30 degrees between the stab and the elevator for downward deflection.
For the V tail option, use a plywood base and place your stabs at 110 degrees from each other. Using triangular stock place in the wedge created and fill will balsa dust and cyano combo, this is light and practical filler.
Elevator ball link control rods
Using 2mm piano wire, you can make your control rod. Taking a 5cm piece, bend it 55 degrees 2cm down from the end. Now turn this perpendicularly an bend the last cm of the other end 90 degrees. Be sure to make a left and a right side! Adjust as required for fit. Now you can solder a ball link and test try thee fitting.
Once this is done and all is right, you can cover your Vtail and hinge the moving section into place with mylar hinges or using your covering material as a hinge. Tape can also serve as a hinge.
The quickest is to prepare 2 hardwood blocks of 20 x 20 x 3mm size. Drill a 5mm hole in the centre of each block and hammer in gently your mounting nut. Now using double sided tape, place your wing on the fuselage and align carefully. Make sure that the distance from each wingtip to the front and back of the plane are equal.Once all is in place, use a marker and highlight the drill holes. Now drill 2 x 6 mm holes in the fuselage. The next step is quite tricky and what I do is wax my plastic bolts, position the 2 mounting blocks on a piece of wood and fit into the fuselage, using the bolts for support, screw them in and position your mounting blocks using epoxy. Once all is dry, remove the screws and trial fit the wing. One can position the wing when the glue is gelling, but you stand the risk of pushing the wooden blocks down.
The stab can be glued onto the fuselage platform with the help of epoxy, make sure all the alignments are correct and that all distances are equal. The stab can also be positioned on the fus as per the wing, but with 2mm nut and bolt option.
Deponding on the version you have chhosen, the fuselage will require 4 micro servos, a receiver and a 4-5 cell 350mah battery pack. This plane was designed around these items so upon completion of this project, it should balance without any aditional lead.
The servos are positioned on the wooden mount as per the diagram below. They are held in place with double sided tape and secured with fibretape.
For the 2-3 servo version shorten your wooden mount plate and move it forward to facilitate the CG position.
This wooden mount is held in place with the help of 2 wood screws. You can add wooden mounting blocks on the inside to countersink the screws. Your servos are now all in the fuselage and this is the what makes our models strong. There are no cutouts under the wing to weaken the fuselage. The only holes you will have are the 2 flaperon pushrod exits. I use a file to make these holes and position them as per the distance and depth that I have placed my aileron ball links.
Should you wish to hand launch, a carbon fibre launch peg can be placed about 12cm from the front pylon. A 4mm carbon rod is adequate and the length varies according to your needs. This can be glued or epoxied into place.
Aileron control rods can be made up of2mm threaded rod and cut to length. Screwing and unscrewing of the ball clevises will ensure correct positioning. Your elevator and rudder pushrods are made from 4mm carbon rods and as per the ailerons, we use 2mm threaded rod at each end.
A ballast tube can be added for maximum fun and speed, you can ballast your prodij a further 250 grs. A PVC tube can be glued in the fuselage opposite to the wooden mount plate. I use a 15mm diameter tube and close the far end. Make sure the middle point of your ballast tube in on the CG.
If you have installed a launch peg, this will allow your ballast tube to come and rest against it, and help with the weights not coming out the back. This solution also reduces the weight distribution of the ballast during a launch.
The CG is 80mm from the L.E. For your first flights you cana dd 15grs of lead to familiarise yourself with the model. Débattements et mixages
The control throws are as per the specs below, all positive values indicate a downward movement of the control surface. These measurements are taken at the root of the wing. These values are spot on for 4 axis flying and we use the flaps on the throttle stick of our radios. The neutral fflap position being the middle on the throttle stick. Our radios have the throttle on a spring as per the other channels.
Elevator -9 / +10mm 20% exponential
Rudder -12 / +13mm
Ailerons -15/ +11mm
-30/+20mm (Max for hotstuff) 25% exponential
Flaps -2/0/+5mm (3 position switch)
-10/+12mm (4 axis flying)
Airbrakes -30mm (On a switch or full up throttle)
Compensate on the elevator at -3mm
Test fly your model without ballast and on the recommended CG position
Move your CG back up till 85mm from the L.E. You choose where you feel more comfortable
For strong wind conditions, ballasting the Minij make it a fast ship, with longer trajectories, however not penalising its overall performance and airfoil effitiency. Do not ballast more than 250grs, rather order a MH22variant wing from me and discover the hidden side of this new machine !
(Thanks to EricArnaud – South Africa – for these English Building Instructions)