If you visit the Walkera V400D02 thread, you will find that it's no secret that the V400D02 frame is very lightweight and flimsy. Many RCG members have reported that the upper portion of the frame just below the main motor is prone to cracking; and once that happens, strange wobbles begin to present during spooling. The lower portion of the frame is easy to bend, as well, thereby changing the shape of the battery cage and giving the heli a noticeable lean when sitting on flat ground. Moreover, the plastic boom mount is easy to snap in a moderate to hard landing. Aftermarket parts must be purchased in order to reinforce the boom.

I have never been a fan of the V400D02 frame. One problem I found is that the battery must be loaded into the frame, thus limiting the size and dimensions of the batteries that may be used. Another problem I encountered is that it is difficult to secure the battery inside the frame. Walkera supplies stiff rubber bands with the V400D02, but I didn't like forcing rubber bands onto the frame every time I loaded a battery. Velcro seemed to work pretty well, but then I needed a spatula to insert and remove the battery.

Another annoying aspect of the V400D02 frame is that it limits the types of cyclic servos that may be used. Small brackets are utilized to secure the stock servos to the frame. I had to cut and hack the servo cases to fit them into the brackets, remove a portion of the V400D02 frame for clearance, and drill new holes in the brackets just to fit the servos onto the heli. Then, I had to repeat this procedure if ever I needed to replace a servo. In addition, there simply is not very much room on the frame for loading all the electronic components that go into changing the V400D02 from brushed motors to completely brushless motors.

One ringing positive about the V400D02 is the stability and simplicity of the Rx2614V. The 3-axis gyro in the Rx2614V actually performs very well, even in windy conditions. The Rx2614V works very well with the popular Hitec HS-5055MG servos, and the tail response with the brushless motor is immediate and crisp. I have never had a receiver lock-out, or even a brown-out with the Rx2614V, either. I would say that the Rx2614V is my favorite part of the V400D02.

So, then I had an interesting thought: Why not take all of the electronic components out of the V400D02 and then install them on a 450 Pro frame? The 450 Pro frame is a proven winner--it is super durable in crashes, rigid enough to prevent aberrant spooling wobbles, offers plenty of room for installing a variety of different servos, and has plenty of open space for mounting the electronics. Moreover, the 450 Pro frame utilizes parts that are widely available, very affordable, and more durable than many of the parts on the V400D02, such as the main gear and anti-rotation bracket.

The accompanying pictures show my attempt at creating a 'Hybrid 450 Pro.' All of the electronics came directly from my fully brushless V400D02, with the exception of a brand new 40A ESC that I installed to compensate for the larger 325mm main blades on the 450 Pro. The frame is an inexpensive VWinRC 450 Pro clone that originally included a torque tube tail with a drive shaft and gears. All of the TT tail components went into a box in the garage to allow for installation of the brushless tail motor and wires from the V400D02. I was pleased to find that the tail motor mount conveniently bolts directly onto the outside of the TT tail box, which considerably simplified assembling this heli. Unfortunately, the main rotor head was not as cooperative. After assembling the whole heli, I discovered the rotor head was warped quite a bit--enough to create very noticeable vibrations throughout the heli. My experience with clone helis has taught me not to mess around with the rotor head, and so I installed an Align rotor head, washout arms, and main blades, all of which I already had on hand. These superior components made for a very smooth heli, indeed.

Upon first flying the Hybrid 450 Pro, I found it behaves a lot like any other 450 Pro--not surprising really, only the brushless tail motor is truly different than a typical 450 Pro. However, this heli is much smoother than I have yet been able to achieve with any TT tail. And, the Rx2614V keeps the heli just as stable as I had originally predicted. Once the settings on this Hybrid 450 Pro are dialed, I expect this heli should be a lot of fun for quite a while to come.

Very nice documentation nav. Cant wait to see it in action.

Hi Kdean, thanks for the compliment.

Thats a sweet set up there. Really thinking about doing this soon. Where did you buy the 450 pro kit from? You going to get a video of it flying?

Hi Ranger,

The kit is a VWinRC 450 Pro clone that I purchased on ebay. An identical kit is located on this page:

450 Pro Flybarless Rc Helicopter Kit

Originally Posted by navigator2011

Hi Ranger,

The kit is a VWinRC 450 Pro clone that I purchased on ebay. An identical kit is located on this page:

450 Pro Flybarless Rc Helicopter Kit

Thanks

Navigator2011,

Thanks for confirming my thoughts this morning. Yesterday, I slipped and landed sideways from about 5 feet going roughly 5-10 mph in a very slow flat funnel. This is the third time I will need to replace the plastic frame supports front and rear. This will be the fourth canopy and fifth spur. I'm tired of rebuilding this heli and refuse to spend any more money on it. I do love the way it flys and the 2614V reciever. I of-course, like so many, upgraded to D213F MG servos after a stripped servo on the maiden flight. I'm looking at a budget frame, like this one and am curious to know a few things:
1) What is your brushless tail motor? Looks like a Tunigy 22XX from the photo.
2) Obviously, you altered the tail rotor mounting. Can you explain what you did please?
3) I noticed the signal converter wires wrapped around a toroid. Was this necessary or just a pet-peave?
4) Is this build light enough to get 6 sec sport flights with 1300 3S Lipos that came with the V400D02? I'm heavily invested in this size battery, mainly for my Techone Yak54. It was one of the things that attracted me to the V400D02.
5) Any other specs that could be useful? Will be very appreciated.

Thanks Again,

Hi ChuckLee,

Thanks for your interest in my Hybrid 450 Pro build. Please find my answers below:

1) What is your brushless tail motor? Looks like a Tunigy 22XX from the photo.

Yes, the brushless tail motor is the Turnigy 2211 (I think that's the correct number) that is part of the RTF-Heli Direct Drive (DD) Brushless Tail kit. I originally had the brushless tail on the V400, and I found that the kit adapts quite well to the 450 Pro. I was pleased to find that the brushless tail motor wires fit very easily through the 450's boom, and that they were more than long enough to pass through without having to cut and then extend the wires.

2) Obviously, you altered the tail rotor mounting. Can you explain what you did please?

Again, there is an element of luck here as the brushless motor mount holes have the same spacing as the 450 Pro tail box holes. First, I pulled all of the bearings, gears, and the shaft out of the 450 Pro tail box, and then gave the remaining parts a reasonable cleaning. Second, I flipped the metal plates on the tail so that the protrusions that otherwise support the shaft bearings are on the inside of the tail box. This creates a flat surface for mounting the tail motor. The bolts that hold the right metal plate (as viewed from the rear of the tail) onto the metal tail unit (to use Align's terminology) are just long enough to also hold the brushless tail motor mount onto the metal plate. So, my third and final step was to assemble the tail box and brushless motor using thread lock on everything, and then pass the wires into the boom where the umbrella gears once were. A single zip-tie holds the wires in position to protect the delicate wires to the Turnigy motor.

3) I noticed the signal converter wires wrapped around a toroid. Was this necessary or just a pet-peave?

Well, it's actually not the signal converter wires that have the toroid, rather it is the brushless ESC lead to the throttle port. As I have read, the toroid is actually necessary to squelch RF noise and its effect on the receiver. This 40A switched ESC came with the toroid already wired, so there was nothing tricky to assemble. Another concern that I had was RF interference with the signal converter chip being so close to the toroid. I have not experienced any ill effects.

4) Is this build light enough to get 6 sec sport flights with 1300 3S Lipos that came with the V400D02? I'm heavily invested in this size battery, mainly for my Techone Yak54. It was one of the things that attracted me to the V400D02.

I am sorry to have to say that you cannot use the 1300mAh battery that came with the V400. One reason is that the 1300 battery is too light to balance out the center of gravity on this much heavier helicopter. Another reason is that 1300mAh is just not enough juice. I'm running 2200mAh batteries for 5 minute sport flights, which leave the cells at around 3.75V per cell (the bare minimum, as far as I am concerned). The heavier 450 Pro frame requires a much higher head speed in order to stabilize the heli than does the V400. I am using the Alpha 400 motor from my V400 on the 450 Pro. On the V400, I could get away with 30-40% throttle and have a very smooth, stable heli. On the 450 Pro, however, I am running 70-80% throttle to get smooth behavior, and that is with the bigger blades, too. Moreover, such a high head speed demands more current to the brushless tail motor. It is this situation that initially worried me about overheating the ESCs and tail motor. I am happy to say that overheating is not an issue at all. But supplying enough power to run this whole system definitely is an issue.

5) Any other specs that could be useful? Will be very appreciated.

Returning to question 3 above, I should also like to point out the importance of running the ESC lead with the toroid separately from the servo wires. On all my birds, especially those having the toroid, I bundle all of the servo wires on one side of the carbon frame, and I mount the whole throttle system on the other side. It is my intension that the carbon fiber frame act as a conductive shield between the servos wires and the throttle system.

Thanks Navigator2011,

These are just the kind of details I need to make an informed decision and your answers really help.

2) I was refering to the "rotor" in the small spinner but I do appreciate the explaination of the motor mounting. I take it it is held on by 2 screws not 4? Obviously you chucked the bearing in the tail rotor. Did you have to drill/ream out the hole in the rotor to fit the spinner?

3) Correct.. the throttle wire from the ESC on the way to the converter. I would definitely use it if it came with the ESC.

4) Bummer.. I was afraid you were going to say that. Man I hate having to buy new larger batteries. I do like the reviews on the Techone Swift. It uses 2200 S3. Maybe in the spring.

Well, I've got two other choices. I'm two signal converters (I'll get them tomorrow) away from my FBL CopterX 250 with 2614V. Please don't spoil it for me but I'm praying the ebay converter (reciever to brushless) will output the correct signal to operate the tail servo. I've got an old Axe CPV3 I could possibly transfer some things over to. The FBL head from the V400 would have to transfer. I'm a pessimist, so not too confident with that.

Well, Christmas is com'n. Maybe a Mini CP that can take a few flops in the back yard. LOL!

Hi ChuckLee,

Yes, the bearing in the tail rotor is saved in a zip-lock bag (I always keep that type of stuff). As I recall, I did drill out the tail rotor to a size just slightly less than the size of the shaft of the prop adapter. I cannot remember the drill size because I actually did that bit months ago when I first received the brushless tail upgrade. There also were a couple of notches on the back side of the tail rotor--I just ground those down. Friction alone has been plenty to keep the tail rotor locked in place.

I know what you mean about batteries, I don't like having all sorts of different sizes, either. Since my other build is a 450 Pro with the CP tail, I have decided to settle on the 2200 3s type batteries.

I don't mean to spoil anything, only provide solutions to potential problems. The signal converter for the brushless motor conversion will not power a tail servo. In order to power a tail servo with the Rx2614V, you must use a TAIL RUDDER-TO-SERVO CONVERTER.

Thanks again,

Just ordered the tail to servo converter. I'll get an RMA and return one of the one others. Thanks for the heads up.

Ahhh, so you bought two bushless motor signal converters? Yes, those will not work with the tail servo; but as you know, you will need one of them to run the brushless main and tail motors.

Hope it all works well for you.

Hi guys, I finally got a couple of videos of my Hybrid 450 Pro cruising around the front yard:

Hybrid 450 Pro Cruising (5 min 10 sec)

Hybrid 450 Pro with Brushless Tail Motor (5 min 25 sec)

Hi what settings did you use in tx? Are you using 2801? I am thinking of building the same, using your notes, I am buying a 450 size motor and 40 amp esc. Any advise would be appreciated

Hi Wrathe73, remember that this particular heli is using the Rx2614V from the V400D02, so my particular settings in the Tx2801 Pro may yield different result than for you. What I did was tweak the pitch curve until it gave me the desired blade pitch at the various throttle stick positions. My blade pitch numbers are pretty simple: -5 degrees at low-stick, 0 degrees at mid-stick, +5 degrees half way between mid-stick and high-stick, and +10 degrees at high-stick. My throttle curve with the Alpha 400 motor is: 0%, 60%, 80%, 82.5%, 85%. From memory, I think my gyro is 70% for heading-hold mode, and 30% for rate mode. I don't use any Travel Adjusts, Dual Rates, or SubTrims at all. As for EXPO, I think for the cycle I am at +30%, and rudder is at -30% to sharpen up the tail response.