Originally Posted by juang1430

In for a penny stock here.. lol...

In my 2 1/2 cents opinion on the tail motor, normally a brushless main motor is designed for 11.1v atleast. Therefore, to suit this mod, you have to use an 11.1v tail motor as well, be it a brush or be it a brushless tail motor.

A guy named hadriez sent a video (on youtube) of him flying an f45 using a brush tail set of a walkera v400d02 if im not mistaken. I have posted the video here previously. I think this tail set is suitable to compensate an 11.1v system (as the tail motor is designed for 11.1v also) and the boom is longer than the stock too which may help to introduce a more stable flight.

I had posted that video already in this thread quite a long time ago and we had already talked about the possibility to change the length of the tail boom, and use an 11.1volts battery like Hadriez is using seemingly with no trouble at all!! IMO the BL setup main motor works quite well with 7.4 volts only thing is you have to limit your flights to about 9 mins because after the 10min mark you start losing power and tail authority is highly affected when battery is low!! Also I think that if you increase the length of the tail boom you will increase that strange bobbing that sometimes seems to afflict the F45 in certain situations!! Basted wind is blowing hard again today and I overslept this morning so didn't get the chance to test the walkera blades yet outside

Originally Posted by markkona

I had posted that video already in this thread quite a long time ago and we had already talked about the possibility to change the length of the tail boom, and use an 11.1volts battery like Hadriez is using seemingly with no trouble at all!! IMO the BL setup main motor works quite well with 7.4 volts only thing is you have to limit your flights to about 9 mins because after the 10min mark you start losing power and tail authority is highly affected when battery is low!! Also I think that if you increase the length of the tail boom you will increase that strange bobbing that sometimes seems to afflict the F45 in certain situations!! Basted wind is blowing hard again today and I overslept this morning so didn't get the chance to test the walkera blades yet outside

Thanks for the credit Mate... Well, what do you know! my 2 1/2 cents thought turned out to be not bad at all!...... and just for your info, not necessarily caused by a longer tail boom, bobbing or jerking usually associated with a weak / malfunction or overheated tail motor.. If you often encountered this problem, try to use heat sink just to prolong the life span of the tail motor..

I think the main drawback of a longer tail is that during forward flight, it acts more strongly like a wind vane, and will take more effort to make it turn.

A shorter tail will improve responsiveness since it has less front-to-back resistance. Also a longer tail mean larger turning circle for the tail, so while the tail will have more "leverage". Even stationary pirouettes will be slower as it has to travel further to complete a rotation.

Food for thought

Originally Posted by slothy89

I think the main drawback of a longer tail is that during forward flight, it acts more strongly like a wind vane, and will take more effort to make it turn.

A shorter tail will improve responsiveness since it has less front-to-back resistance. Also a longer tail mean larger turning circle for the tail, so while the tail will have more "leverage". Even stationary pirouettes will be slower as it has to travel further to complete a rotation.

Food for thought

This is an awesome explanation and really make sense... thanks & cheers...

Originally Posted by juang1430

Thanks for the credit Mate... Well, what do you know! my 2 1/2 cents thought turned out to be not bad at all!...... and just for your info, not necessarily caused by a longer tail boom, bobbing or jerking usually associated with a weak / malfunction or overheated tail motor.. If you often encountered this problem, try to use heat sink just to prolong the life span of the tail motor..

I don;t worry about the life span of my tail motor it has been going strong since april 2012 so far

Originally Posted by markkona

I don;t worry about the life span of my tail motor it has been going strong since april 2012 so far

Good for you...

Hi Guys

I'm going brushless, the main motor seems a little weak.

I want to keep the stock 2 cell battery and stock tail motor.

I'm thinking this motor, since the EH200 is hard to find.
http://www.hobbyking.com/hobbyking/s...or_4200kv.html

Can I use this ESC, or do I need a other one?
http://www.hobbyking.com/hobbyking/s...ontroller.html

Any thoughts, do I need something more to get this setup working.

Originally Posted by Flyor

Hi Guys

I'm going brushless, the main motor seems a little weak.

I want to keep the stock 2 cell battery and stock tail motor.

I'm thinking this motor, since the EH200 is hard to find.
http://www.hobbyking.com/hobbyking/s...or_4200kv.html

Can I use this ESC, or do I need a other one?
http://www.hobbyking.com/hobbyking/s...ontroller.html

Any thoughts, do I need something more to get this setup working.

You will definitely need a pinion to fit on the BLmotor shaft as stock won't fit since it's 2mm shaft!! I don't know if this combination will work but on someone on youtube had success with a BL inrunner motor on his F45 I will try to search the link for you.


OK HERE's one

MJX F-45 Brushless Conversion + Flight (3 min 53 sec)

and here s another if you understand german

Testflug MJX F45 , F645, mit Brushless Vector Inrunner, 370er 6900KV (7 min 36 sec)

Originally Posted by Flyor

Hi Guys

I'm going brushless, the main motor seems a little weak.

I want to keep the stock 2 cell battery and stock tail motor.

I'm thinking this motor, since the EH200 is hard to find.
http://www.hobbyking.com/hobbyking/s...or_4200kv.html

Can I use this ESC, or do I need a other one?
http://www.hobbyking.com/hobbyking/s...ontroller.html

Any thoughts, do I need something more to get this setup working.

ESC is fine, anything more than 12 Amps should work I believe. Higher amps means less chance of it overheating under heavy load. eg if the motor pulls 10A at full stress, the 12A ESC will get quite warm, where as the 18A wont get very warm at all.

In terms of the Motor, the one you linked will work, however, you will need to modify the body of the F45 either by cutting or bending, or both, as it only has a 24mm space where the motor sits, and that motor you chose is 26mm wide.

Other than that it is just fine.

Oh and you will need a new pinion as well, such as this: http://www.hobbyking.com/hobbyking/s...dproduct=11198

As the stock is only 2mm, where as you will need a 2.3mm pinion. Might have better luck on eBay though as HK is out of stock

Some time ago word was going around that a heat sink won't be able to lower the heat significantly.
Today I measured the temperature of two more flights, giving a total amount of 6 times flying with heatsinks installed head and tail.
It does help a lot! Not only during the flight, but the cool-off effect after landing is also much faster...
I didnt look at the temperature at each flight. But the head + tail motor are still running smooth after a total of 48 flights.

more interesting are the temperatures measured at the main motor because i didnt measure the tail motor's heat until i installed the heatsink.
the temperatures of the first few flights were lower because i was very carefull not to destroy the mjx instantly.
The first higher peaks indicate when i was able to fly harder.

data sheets:
main motor



tail motor

Originally Posted by slothy89

ESC is fine, anything more than 12 Amps should work I believe. Higher amps means less chance of it overheating under heavy load. eg if the motor pulls 10A at full stress, the 12A ESC will get quite warm, where as the 18A wont get very warm at all.

In terms of the Motor, the one you linked will work, however, you will need to modify the body of the F45 either by cutting or bending, or both, as it only has a 24mm space where the motor sits, and that motor you chose is 26mm wide.

Other than that it is just fine.

Oh and you will need a new pinion as well, such as this: http://www.hobbyking.com/hobbyking/s...dproduct=11198

As the stock is only 2mm, where as you will need a 2.3mm pinion. Might have better luck on eBay though as HK is out of stock

The 4200kv motor has a 2.3mm shaft, but lower at the Product Config Table 2mm whitch is it

Now I understand why the EH200 is a better option, only 23mm wide should fit easier :-) maybe it's better to wait a while until I find one of those.

Greetings
In that video with the Park 370 Brushless Motor the helicopter is running the stock blades. Would that make sense if he is sticking with the 7.4v power supply?

http://www.horizonhobby.com/products...100kv-EFLM1000

That's an expensive motor!

I think I'm going to order the EH-200 from another vendor depending on their shipping costs. I'm trying to decide if I should try the 5000kv version with stock voltage like in the video or go for the 4100kv version and get a new 3C Lipo. I think I can convert for ~ $50-$75. My hope is that will tie me over until I pick up one of those Carbon Fibre frames and start building one of those up, or go for the same in a Quad.

Originally Posted by Stoersender

Some time ago word was going around that a heat sink won't be able to lower the heat significantly.
Today I measured the temperature of two more flights, giving a total amount of 6 times flying with heatsinks installed head and tail.
It does help a lot! Not only during the flight, but the cool-off effect after landing is also much faster...
I didnt look at the temperature at each flight. But the head + tail motor are still running smooth after a total of 48 flights.

Hell Störsender, the word was from me !
Of course the heatsink helps to lower the temp, but essentially at the outside of the motor (housing and magnets of the stator)
But what gets the hotest are the rotor and the brushess, wich are not in contact with the heatsink, and are therefore just marginally cooled by the heatsink.
On my first F45, both motors have heatsinks, tail motor died after 50 flights, and main motor after 55 flights.

But again, just my 2 cents

Originally Posted by rexless

Greetings
In that video with the Park 370 Brushless Motor the helicopter is running the stock blades. Would that make sense if he is sticking with the 7.4v power supply?

http://www.horizonhobby.com/products...100kv-EFLM1000

That's an expensive motor!

I think I'm going to order the EH-200 from another vendor depending on their shipping costs. I'm trying to decide if I should try the 5000kv version with stock voltage like in the video or go for the 4100kv version and get a new 3C Lipo. I think I can convert for ~ $50-$75. My hope is that will tie me over until I pick up one of those Carbon Fibre frames and start building one of those up, or go for the same in a Quad.

I would not suggest the 5000kv on 7.4 volts.
I used that in my firefox CP and it did not work well. With full battery, it was OK.
When battery got to about 7.8 to 7.9 volts, the power was hardly enough to keep in the air and that heli is half the weight of the F45.

Originally Posted by Flyor

The 4200kv motor has a 2.3mm shaft, but lower at the Product Config Table 2mm whitch is it

Now I understand why the EH200 is a better option, only 23mm wide should fit easier :-) maybe it's better to wait a while until I find one of those.

Damn and to think about a month ago McDonald's were giving a free EH200 with every mcFlurry you buy and eat