The last time I converted this Nine Eagles Xtra 300 model I used a quite large Turnigy park flyer (bell type) out-runner. It did the job very well but was heavy and required 500 mAh + to have any kind of decent flight time. Until only very recently I've been having some bad luck with models and decided to just get another Xtra 300 to have some fun with.
Then I remembered since the last time I now have some small 11g brushless out-runner motors which are much smaller but with same thrust. While I would still have to do a little cutting to make this work the overall result should be much smarter, lighter and therefore not require bigger lipo packs.
In this project I am using:
FrSky 4 channel Fasst receiver stripped out of the case and heat shrink wrapped. (3.8g)
3 * Turnigy micro servos 1440A (3.8g each)
Micro Brushless Outrunner 2000kv (18-11) linked above. (says 10g but actually closer to 11g)
250mAh stock nine eagles 2S and also my own 2S 300mAh lipo packs. (9g & 11g)
My end AUW weight ranges 109g to 111g depending which lipo. Either way its just 10g - 12g over stock weight (mine was 98g stock), but in return I should have longer flight times with more power and greater agility from further servo throw.
Before starting you should decide if you want to buy a module to convert analogue to digital for brushless and just upgrade the motor (search RC groups on this). However if like me you want to only have 1 transmitter and not 20 million lol then replacing all the electronics is the only real way to go.
So first carefully remove all the existing electronics only! By this I mean leave the control lines and aileron pivot arm. Remove the aileron control board, RX brick with plastic mounting bracket and entire motor + mount. The mount is a little tricky but just take your time with some needle nose pliers or similar.
Now to fit the better motor we need a decent firewall to mount on. To do this I opted to cut into the bottom of the fuselage where it's just plain EPO foam, I made the cut just deep enough for the motor shaft to stick out the front.
Important: if you want to return your model back to stock looking then try make the cut out in one go and KEEP IT!
To make the firewall mount I cut some of the foam out of the box the model came in, however any thick foam will do the job or plywood or plastic ..
Remember to make a cut out hole for the ESC wire to pass to the RX and battery compartment. (visible in the top of my firewall in the photo)
Once you mount the motor in place (remembering a little down and right (1-2 degrees) to counter motor torque you can begin trimming the original cut out as a "panel" to fit back over your cut out using the top clean side.
You can see the motor is not stock but it doesn't exactly look out of place and rather tidy seeing as the fuselage was just cut open.
You can see the female JST socket ready in the battery compartment just like the stock set-up.
The elevator and rudder control lines are already there to use, simply unscrew the collar from them so your left with just the control line. The using a piece of steel wire (1<>1.5MM) bend your own connectors with about 30-40MM excess. Overlap the excess with the existing control line and use heat shrink pipe sliding both lines through.
Line up the controls so everything is center then run CA down the heat shrink and carefully using a soldering iron just run it past the heat shrink pipe, excess CA will come out but when dry it will be a solid bond.
A small tip for adjusting the servo control horns even when glued in, take off the black canopy carefully as you can stick it straight back on using original glue. Prod 2 holes in-line with the servo heads to poke a screw driver through, doing this you can remove the control horn and put it back (a bit fiddly) but when you put the canopy back you hide your holes. The receiver you can see is as far forward in the fuselage bay as possible. Remember the aileron control lines still have to sit in there.
To simplify the aileron set-up I kept the original pivot arm in place and used a small screw to fix the original arm to my servo arm. Its tight enough to not twist out but is thin enough for the arm to move freely without resistance. This was by far the most simple step.
It was dark when I dropped the model onto the bed to find it landed on Garfield lol, he just sniffed it and went back to sleep.
Anyway you can see the model now finished RTF (ready to fly) with its bigger prop and new set-up. As I wanted the only thing that makes it look not stock is the motor, the rest looks as normal.