quorneng
Master member
In 2019 I built a 250g (exactly!) Canberra B2 in 2mm Depron that used low power 35mm 6 blade AEO EDFs.
Using an 850mAh 2s (the EDFs were only rated for 2s!) it actually flew pretty well but at the scale I used the EDFs were too big to fit within a scale nacelle so were placed right at the front which at least allowed the feeble EDFs to "breath" freely.
I wondered if I used modern 30mm EDFs I could make another Canberra of the same size but keeping to true scale nacelles.
In the UK the special 250g category no longer applies so I chose to print the nacelles using LW-PLA where the efficiency of the duct would hopefully counter any increase in weight.
Each nacell is printed in 5 parts.
Front and back inner duct and outer nacelle profile with a combined rigid centrepiece that carries the wing spar across the nacelle. The EDF is fully supported by the inner and outer sections at the nacelle nose so the bell mouth is retained.
The nacelles are joined by a printed box spar that runs through the fuselage.
The outer wing panels use a printed D box section also in LW-PLA using a true scale symmetrical section.
The inner and outer wing panels are a built up structures in 2mm Depron.
The Canberra fuselage has the advantage of using a circular cross section front to rear so the fuselage formers are also LW-PLA printed.
The fuselage built in front and rear parts and each as a planked structure using 2mm Depron as a half shell over the plan. Then rather like the Mosquito each half shell is simple glued together!
A view inside the completed nose section.
The rear fuselage added to the nacelles and box spar.
The inner and outer wing panels added.
Note the inner panel ahead of the box spar is omitted to allow the EDF wires to be passed through to the fuselage Also the outer panels are tissue covered to save weight.
With the nose added it was possible to determine that the 850mAh 3s would be placed in the cockpit area so the offset canopy became the handle for battery hatch.
With the structure complete and all glued together I chose to paint it with a "desert" camo, "desert sand" upper and pale grey under.
Even the roundels were 'no white'. matt and very pale.
Not ideal for an RC plane being virtually invisible at any distance but then I suppose that was the whole point!
To my relief despite being 20% heavier than the B2 it flies nicely although it is a bit faster yet gives a 4 minute flight with a bit of throttle management.
Not exactly a simple build but then neither was the all Depron B2.
Using an 850mAh 2s (the EDFs were only rated for 2s!) it actually flew pretty well but at the scale I used the EDFs were too big to fit within a scale nacelle so were placed right at the front which at least allowed the feeble EDFs to "breath" freely.
In the UK the special 250g category no longer applies so I chose to print the nacelles using LW-PLA where the efficiency of the duct would hopefully counter any increase in weight.
Each nacell is printed in 5 parts.
Front and back inner duct and outer nacelle profile with a combined rigid centrepiece that carries the wing spar across the nacelle. The EDF is fully supported by the inner and outer sections at the nacelle nose so the bell mouth is retained.
The nacelles are joined by a printed box spar that runs through the fuselage.
The outer wing panels use a printed D box section also in LW-PLA using a true scale symmetrical section.
The inner and outer wing panels are a built up structures in 2mm Depron.
The Canberra fuselage has the advantage of using a circular cross section front to rear so the fuselage formers are also LW-PLA printed.
The fuselage built in front and rear parts and each as a planked structure using 2mm Depron as a half shell over the plan. Then rather like the Mosquito each half shell is simple glued together!
A view inside the completed nose section.
The rear fuselage added to the nacelles and box spar.
The inner and outer wing panels added.
Note the inner panel ahead of the box spar is omitted to allow the EDF wires to be passed through to the fuselage Also the outer panels are tissue covered to save weight.
With the nose added it was possible to determine that the 850mAh 3s would be placed in the cockpit area so the offset canopy became the handle for battery hatch.
With the structure complete and all glued together I chose to paint it with a "desert" camo, "desert sand" upper and pale grey under.
Even the roundels were 'no white'. matt and very pale.
Not ideal for an RC plane being virtually invisible at any distance but then I suppose that was the whole point!
To my relief despite being 20% heavier than the B2 it flies nicely although it is a bit faster yet gives a 4 minute flight with a bit of throttle management.
