I already built one of these, and I have been flying it for 4 seasons. I've flown it off the runway, grass, water and snow. It handles wind easily.
See the link for my original construction thread, including a few modifications.
https://temac.ca/smf/index.php?topic=7850.0
In this thread I will not post all construction, nor any of the previously posted modifications, but I will post any new modifications, and the 4 motor setup I plan. The motors will be mounted in scratch-built nacelles on the wings.
These photos are of the model that I am currently flying.
The first photo isn't a modification, but simply to show that I've started construction.
The other photos show that I've enlarged the battery hatch to make it easier to place and take-out batteries from the fuselage.
I used a couple scrap pieces of plywood to hold the enlarged hatch together.
Fuselage construction is finished.
Modifications:
- The battery hatch is larger to accommodate larger batteries.
- The windshield is removable to facilitate adjusting a 3-way gyro-stabilizer when the model is fully assembled.
- The fuselage side sheeting is constructed separately from the fuselage supporting structure. Since I likely didn't build either of these perfectly strait, they didn't line up, so I cut the side sheeting in half, trimmed it to fit, glued the pieces on, and glued in scrap balsa, so everything would line up.
- Instead of using one long laser cut part to cover the front-bottom hull, which was difficult due a needed curve against the grain, I used some scrap balsa to sheet this area with the grain parallel to the curve.
The wing is next.
Nice looking fuselage.
It will be interesting to see the nacelles for the motor and all that wiring.
Sure is fun when you have a project on the go.
This is important if any of you intend to build this model.
Step 31 of the instructions says to "Position and glue" the ribs to the wing spar.
Don't glue yet!
Unless the 1-piece vertical webbing piece of balsa is installed first (step 32), which has slots for each rib, the rib spacing is impossible to determine. There are no plans; the fuselage and wings are built as a 3-D assembly.
Also, the various wing spars, including the 1-piece vertical webbing piece of balsa, have a 1/8" tab at one end, and a 3/32" tab at the other end. These tabs are "seats" for inner and outer ribs. The 1/8" tab is for the inner wing; the 3/32" tab is for the outer wing rib. This is not indicated in the instructions.
Make sure to build a right wing, and a left wing.
The wings are coming along nicely.
As with my previous build/model, I added a carbon-fiber wing joiner after a crash due to a broken dihedral joint.
On this model I custom-built a snug-fitting carbon-fiber and plywood dihedral joint, which will be used instead of the (built from 2-piece of plywood) joiner supplied in the kit.
Otherwise, I'm building the wing mostly as per the instructions.
I intend to finish all balsa and plywood construction of the model before customizing it for the 4 electric motors.
That is one very strong joint.
Main construction is done. After some sanding, I'll dry-fit/assemble the components, prepare the 4 motors, speed controls, and wiring, and then scratch build nacelles.
I've started on the nacelles. It's taken me several hours to think, plan and prepare a design.
I had to take into consideration:
- the wing dihedral, the two sides of a nacelle will be different.
- motor size and mounting
- speed control and wiring
- attachment to the wings
This exaggerated drawing/diagram shows why the nacelle sides are different.
I want the wing to look like the image on the bottom. If both sides were the same, the wing would look like the upper image.
Basic design and basic construction of the nacelles is done. These will be sanded and edges rounded, and access-hatches made for the bottoms.
This took a lot of planning and more time than anticipated.
Slow but steady progress.
Michael,
Can you describe the math on the motors- total watts?
Looks like it has more than enough power to take off water.
Great project.
Frank
ps: every time I see you build on the pool table I think of the Beverly Hillbillies episode where they sit around the fancy eating table with the fancy pot passers (cues).
Photo below;
Quote from: Frank v B on February 07, 2025, 08:15:46 PMMichael,
Can you describe the math on the motors- total watts?
Looks like it has more than enough power to take off water.
Great project.
Frank
Good question.
Here's my fuzzy logic .....
I'm using 2 sets of twin motors and speed controls from Flite Test Widgeons; these are the mid-size foamy twins that a few of us fly at the field. The planes weigh approx. 2½ pounds.
These use 1250KV motors with 30 amp speed controls, on a single 3-cell 2,200 mah battery packs. They provide enough power to take off from any surface, and to fly vertically (really, really high) without stalling. I do not know how many amps are being drawn, nor how many watts are being produced.
I did however, put one of these power systems in a heavier scratch-built plane, and it also flew very well.
My older Seagull flies easily with a .25 eflite motor on a 4-cell 5,000 mah pack. This planes weighs approx. 5 or 6 pounds.
I simply figured that 2 of the Widgeon systems should be more than adequate for this project. Power will be provided by separate wiring to the outer and inner motors, but all from a single 3-cell 5,000 mah battery pack. Propellors on will spin in opposite directions to opposing wings (from the back; left wing clockwise, right wing counter clockwise).
My personal experience is that twin motors seem to produce more efficient thrust than what twice what a single motor would be expected to provide. I'm guessing, also based on some experience, that 4 motors will be even more efficient.
Lots of planning and thought, receiver bound to transmitter, power through a separate BEC, a bunch of wire, some soldering, aileron servos, and wingtip lights.
Tomorrow: secure and label all wire connections, build hatches for the nacelles, and if time allows, finish the wing floats.
Michael,
I believe the wingtip lights are backwards...unless I am colour blind or the wing is upside down.
red = left = port
green = right = starboard.
There must be a rat's nest of wiring in this plane.
Frank
(sorry)
The wing is upside down.
Green has 5 letters; Right has 5 letters. Easy to remember.
Outer-wing floats.
In my experience, these tend to break off on less than perfect takeoffs and landings, when there is side pressure.
My solution to this problem is, instead of gluing them on permanently, I use strong magnets to hold them in place, but they will detach without any damage, in event of strong side force.
2 days of work!
@Michael that is enough magnets to change the earth's magnetic poles!
Love to see your progress.
Thank you for sharing.
The floats need to be firmly attached, but still be able to break away before damaging anything.
I'm preparing the model for covering, but first painted the nacelle interiors (visible from the front) black.
This is to give the model a better finished appearance, without showing any wood.
I did this before on a Waterbomber I built a few years ago. See the photo.
Covering has started.
At the suggestion of a friend who works at Great Hobbies, I'm using covering by Dancing Wings, for the first time.
So far, I find it adheres and shrinks extremely well (at about 140 degrees Celsius), but it sticks to itself very easily, and it cannot be pulled apart. I'll have to be careful.
The film itself is very thin, but seems very strong.
The Dancing Wings covering works well. It sticks easily, warps around reasonable compound curves well, and shrinks with heat.
The only problem comes from the fact that the glue side of the film is white, instead of the more commonly seen clear. When the film is tacked down, and then shrunk tight with heat, the white glue shows.
Covering completed!
A very satisfying image.
Assembly and setup in process. Tail attached, ailerons attached.
The third photo is of a new brand of speed control I'll be using; from what I understand, they're Fab!
Wing wiring finished.
Nacelles installed.
Motors and spinners installed. Everything is spinning nicely; the port side (left side of the wing, from the rear facing forward) spinning clockwise and the starboard side (right side of the wing, from the reverse facing forward) spinning counter-clockwise.
Of course, the 3-blade propellors and spinners are appropriate for the directions they spin.
There's just something about multi engine planes!
Quote from: davidk on February 20, 2025, 09:57:42 AMThere's just something about multi engine planes!
I know! It's fabulous when there's 4!
Mostly finished.
I had to change 2 speed controls (they were shutting off with full throttle), I had to adjust thrust angles on 2 motors (the plane was turning left), and there's still a bit more work to do.
The plane here is lacking the spinners on the right wing.
It still needs velcro for the battery compartment, decals and decorations, balancing, and registering.
Radio programming, including gyro controls, are done.
VERY Nice!
Finished; ready for flight.
Successful maiden flight!
Smooth takeoff, level flight at half-throttle, and a gentle, smooth landing.
4 motors sound great. Effortless take-off and landing... such a great flyer. Nicely done.