Kila Watt from Green Air Designs

[Ady Hayward]

Hi, Another build on the way. This one looks the muts n**s for fun flying. Compact and very agile. So, without much ado, here goes:

The brown paper covered box got the suspicious look from my beloved....." what have you been ordering that comes in a plain brown wrapper" she asked...It's a model honest.
On opening the suspicious item there are ridiculously few parts, a nice set of decals and some bubble pack to keep it all sweet and immobile in transit. All items that could rattle around are secured with tape.

The first step for me was the tailplane. A test of my hot glue gun found the heat is too much and the adhesive melted some of the scrap material so epoxy it is for the first bits. The tailplane is reinforced with a piece of aluminium box section which fitted nicely in the slot already cut in the tailplane. The elevators were next in line and had the leading edges bevelled and the locations made for the piano wire joiner. This is bent from the wire supplied and fitted in to the elevators. I used some 5 mnute epoxy here to reinforce the holes made to reduce slop in the system.

The wing panels were inspected and the flashing from the cutting process was carefully removed from the trailing edges. The two halves were joined with epoxy and left to cure.

 

 

Edited By Ady Hayward on 28/04/2010 07:45:47

Edited By Ady Hayward on 28/04/2010 07:48:42

[Ady Hayward]

Onwards and upwards. Still plodding on with the build.
The wing was marked up for the spar as stated in the instructions at 40mm rear of the leading edge on the wing centre line. The spar was offered over the wing and manipulated (Sounds better than just plain bent)to follow the line of the wing surface where it will rest. The 6mmm x 6mm slot was marked on the wing ensuring that it was not offset on the wing, and cut out using a sharp scalpel blade at front and rear edges with a mark on the blade for 5mm depth. Then 45' cuts inwards to remove most of the material. I then used a piece of 4mm balsa trailing edge material with fine glasspaper glued around the edge to give a 4" length of sanding block of the right width to remove the remaining material to the correct depth. Quicker to do than type this!. As my glue gun is too hot and melts the foam I used 5 minute epoxy to glue the spar in place. This was followed by the tip blocks that were shaped once the epoxy had cured.

That completes the wing for now, so on with the fuselage.

Edited By Ady Hayward on 28/04/2010 07:51:38

[Ady Hayward]

The fuselage is simplicity itself....as is the plane in general. A new hot glue gun has been purchased...better temperature, smaller, lighter, uses the same size glue sticks and was only £4.00
The fuselage sides and base were cut out of the main sheet and the retaining pieces sanded smooth to the edges. A little experimenting found that if I put a few very small perforations in to the depron surface to be glued then the edge piece glued on has much better adhesion. Having done this to the fuselage sides where the base joins I hot glued the sides to the base ensuring they were vertical to the base and equal lengthways as there is a little room for adjustment in the slots in the fuselage sides. The fuselage underside was then glued on to the assembly making sure that the fuselage does not get any twist or bend.

The fuselage formers were then glued in place. I placed them adjacent to the wing leading and trailing edge positions. This was followed by the wing dowels forwards of the front former, and rearwards of the rear former. As I didn't have any wood dowel of the correct diameter (5mm, 3/16")I used some small lengths (110mm, 4 1/4") of carbon rod instead making sure there was sufficient fuselage side left above them for strength. I made sure they were as close to the formers as possible and used plenty of hot glue wrapped around the dowel (By spinning the dowel whilst the glue is hot) so a good bond is made to the sides and formers. The tailplane can be glued in place making sure that it is square to the fuselage centre line, followed by the top decking, fin and ventral fin.
 

Slots were cut in the rear of the fuselage base for the two 9g servos for the rudder and elevator. These were held in place with a little hot glue over the mounting lugs. At the front end the fuselage base was trimmed to allow a little right and down thrust and the nicely laser cut firewall was epoxied in place and held until the epoxy cured.

Thats the main build done. Now the final fitting.

[Ady Hayward]

The aileron stock supplied was of very generous length allowing the centre section reinforcement to be cut from either and still leaves more than enough aileron material to complete the aileron installation. The reinforcement piece was cut to the same length as the wing hold dowels and shaped to match the wing surface. This reinforcement piece was then glued to the wing trailing edge with the thin edge forwards. 



When the epoxy had cured it was sanded to fit the wing trailing edge profile. The ailerons were measured up and cut to the same length to fit the wing as desired. Each aileron was placeded on the wing and the aileron shape was marked on to the wing surface. The aileron recess was cut out of the wing with a new scalpel blade and trimmed carefully until the fit of the aileron is good wit around 1.5mm gap at each end.

 

It is intendedto cover the aircraft with tissue and wbpu to enable covering in suitably lurid iron on film.

The above is work done over three days, on and off. It's really quick to build.

Edited By Ady Hayward on 28/04/2010 08:00:05

[Ady Hayward]

Nearly there,
Covered the wings with heavyweight modelspan applied with 50/50 thinned wbpu. Found the best technique is to wet the wing thoroughly with the wbpu mix and lay the tissue on and work from the middle outwards in increasing circles tensioning the tissue as it is stippled lightly. A few wrinkles did appear but were no big and easily sanded when the wbpu had cured. There were three coats of thinned wbpu applied on top of the tissue and sanded between each.

 

The rest of the airframe was given three coats again and was sanded between each. I tried solarfilm covering which went on well at quite a low temperature with good adhesion on to the wbpu. The wing servo was put in the leading edge to allow the best clearance for the possibility of using a 2200 3s LiPo. Pushrods were as suggested by GAD instructions. I put a kink in one to allow adjustment but in reality is not needed as i decided last minute to use clevices in stead of joggle links.
 

Elevator and rudder are operated with 20swg wire in ABS tube for a light slop free linkage. I have two elevator pushrods (one to each elevator) and a single rudder pushrod with the ABS tubes secured using hot melt glue. All controls were checked and adjusted and the rest is awaiting delivery of the motor which happened this morning.

[Reno Racer]

Looks like a cloud models e2k pylon racer, so should fly very well, particularly if lighter.

[Ady Hayward]

Hi Ackers. It does conform to the e2K format and they do fly very well.

Yay! Ready for the maiden.
Applied the nice decals supplied and adding a bit of extra trim later. Weight with a 2200 3s LiPo is 515g (1lb 2 oz) and it climbs out of my hand way before full throttle is applied. Balance point is on the mainspar so all looks good for a lively flight. Timing is set to high on the 25A HobbyWing Guard ESC and throttle response is great. Prop is a 6 1/2" x 4 APC and motor is an ELE Motor 2300Kv powerhouse.

 

Adrian

[Ady Hayward]

Maidened the Kila Watt today in less than ideal weather conditions. Turbulent conditions with around 15mph of wind gusting much more. The control throws I had on elevator +- 40 degrees was way too much. Aileron at +- 30 degrees is very nice and rudder was +- 40 degrees, again good. I also had the balance point just on the rear edge of the spar...it needs to be just on the front of the spar. The first flight was quite entertaining with a slightly aft c of g and too large an elevator movement but she flew well. The second flight was much better with  the elevator throws cut down to +- 25 degrees. The Kila Watt is very agile, can turn very tightly and doesn't need much more than 50% throttle for any manoeuvre. Going full throttle has it going vertical and out of sight very quickly. Snap (Flick) rolls are very rapid but stop on releasing the sticks. Landing is no problem as it glides reasonably well and is very controllable. All in all an aircraft to have mega fun with.
Adrian