What can I say apart from what a little gem this model is ?
Well after spending about 2 hours building this model and installing the servo’s, (most of the time holding the model waiting for the glue to grab) I set about working out the best power package for this model. I know that MPX power sets are always very good, but they are not cheap and wanted to see if I had something of my own to do the job. The recommended MPX motor is around 33g and is a 1180KV but where MPX has been clever with this model is that the aperture where the model fits is smaller than most cheap motors pushing you towards their power kit but I wasn’t going to be beaten. illustrated instructions
From my old model shop days I had some old apache motors and one of them weighing in at only 28g with 1500Kv.
Here are the specs of the motor that I used
Model APS20-34T, Turns 34, 1520Kv
Voltage 2-3 Lipoly, 6-10 NC
Diameter 28mm
Length 18.5mm
Internal Resistance 190m ohm
No Load Current 0.4A
Recommended Current 6A
Burst Current (15-20 sec) 8A
Shaft Dia. 3mm, Weight 28g
Anyway, whilst the motor fits straight onto the motor mount, the motor will not fit inside the nose of the fuselage. This is where some very gentle warming was required rather than cutting away which shrank the material enough to get the motor inside the fuse with catching but then there is no room for the 3 wires.
This is where a bit of bodge is made but it works a treat.

I needed to source the spinner and prop and the only alternative was to get hold of the genuine Multiplex spinner and a pair of Aero-Naut 7×4 prop blades suitable for the spinner. Robotbirds keep these in stock suitable for a 3mm shaft which was good news.
I coupled up the motor to a generic 15A speed controller that I had lying around and fitted a 2.4GHz receiver.
Finally and probably the most important item was the batteries and I decided to try a new supplier.
I ordered 2 x 3S 450mAh packs from www.maxpoly.co.uk

A day or so later the packs arrived. Great service. These packs are perfect size and weight for the Merlin
Not only are these batteries great value for money, but they perform very well. The power to come out of this setup when powered by these little pack is amazing and I rate these packs as highly recommended.
ANYWAY, NOW IT IS BUILT WAS DOES IT FLY LIKE ?
In a word, superb. Very few planes these days put an instant smile on my face. The maiden flight was on a breezy day on the top of hill whilst on a day out to my caravan down in Devon. If this plane had manners, the this one really does mins its P’s & Q’s as a gentle throw at half throttle the plane seemed to gain height in an almost VTOL fashion into the wind with no trimming at all. I pulled back and it gained height with ease. At almost no throttle the plane will sit almost still into the wind, but open it up in a dive and it really does get a rock on. Landing is very easy as the plane levels itself out so well due to the wing design. I made several flights with these new battery packs and after a 10 min flight of varying throttle positions, the battery never required more the 350mA to bring it to full charge.
All in all, these planes are great, whilst not quite for a beginner as they do turn quick but with dual rates set these could make a great little plane with more potential as the pilots experience grows. With high speed passes, low speed circuits and almost slope soaring even with a motor fitted will make this model a winner. Don’t get put off by its size as for a small model it does seem quite expensive, but the research that must have gone into the design and tooling of this model must have been extensive for it to behave so well. This model behaves much better than models with a larger wingspan and with the added benefit of being able to fit it on the parcel shelf this is sure to be a winner.
Well done to Multiplex AGAIN, thanks for great product range from Robotbirds and looking forward to trying some more flight packs from Maxpoly as these 2 packs are superb and excellent value too.
HERE IS THE BLURB FROM MULTIPLEX
Merlin – The little magician
The name “Merlin” can apply equally well to the famed magician or the small falcon, and both descriptions are valid for our little racer.
Finally we can offer a mini-format model with a full-size performance. It’s an all-in solution with many clever detail features, but above all its compact design means that it can accompany you wherever you go.
The Merlin is agile and nimble, while its small size makes it terrific fun to fly even at small slopes. With its low weight and robust ELAPOR® construction the risk of airframe damage is low, but despite this the model can cope remarkably well in windy conditions – this is where the “falcon” aspect of its nature comes into its own.
When flying aerobatics “Merlin the Magician” comes to the fore: the powered version in particular is capable of the wildest aerobatic manoeuvres you can imagine. When the model is complete, it can be transported conveniently in the retail packaging. The aeroplane features a practical hatch in the underside through which the battery can be changed quickly and conveniently
The plus points:
• Simple and quick to assemble – in the air very quickly
• The model can be completely dismantled for transport
• Packed size only 11 x 18 x 61 cm
• Optional transport bag with strap attachment (# 76 3316)
• Can be built as a glider or in an electric version (with power set # 33 2653)
• Docile flying characteristics
• Raised ailerons as landing aid
• High-quality plastic components
• Major parts moulded in ultra-durable ELAPOR® foam
• Carefully matched power system gives great agility; optional increased performance by changing propellers (both sizes included in the power set))
• Li-BATT BX 3/1-450 mAh flight battery
Kit contents:
Moulded ELAPOR® parts, small items, CFRP spars,
decal sheet,illustrated instructions
Specification
Wingspan 783 mm
Overall length 598 mm
All-up weight glider / electric approx. 240 / 290 g
Total surface area 11.3 dm²
Wing loading 21,2 / 25.7 g/dm²
RC functions Elevator, rudder, ailerons (2 servos),
throttle, Landing aid: raised aileron



I have now completed around 30-40 flights on this set-up. Whats worth pointing out is that this model still flies very well on a windy day. Yes it does get blown about a bit, but I have had flights of over 20 mins using the wind to my advantage. Also, the Maxpoly flight packs have now done over 20 cycles each with no sign of the power dropping off despite pulling 10A from them on a regular basis.
hi mart great vid
andy