First impressions on the F550 and first questions

[Fanch]

Hi all!

I just flew my first flights with my F550, stock motors, 8¨props from DJI and a 4S 5000MAH 35C (and Futaba T8J). The two maiden flights were just a dream... no problems whatsoever, perfectly stable with GPS lock.

1-DJI specifies that to fly with the 10¨props you need a 3S while you must have 4S with 8¨. Does anyone knows why?
2-Wich configuration (10¨or 8¨) is more suitable for heavy lift? By heavy I mean lifting a landing skid, Nex5 and down-link. Anyone working with a similar config?
3-DJI motors have a special shaft to avoid that the prop will spin. What kind of replacement props do you recommend and how do they fit on DJI motors?

Thanks for all help

Francois

 

[ProPilotWannaBe]

Francois, I am no motor/prop expert, so hopefully some can fill in some more details, but I'll tell you what I understand:
1) with 4S batteries you are pushing the motors ~33% harder than a 3S, and since 10" props have a larger moment thus it stresses the motors too much at the higher RPMs when you have a 4S.
2) Larger props will give you more lift if they have the same pitch. I have friends in the business that have two F550s with stock motors/ESCs and the DJI 10"x3.8" props carrying a landing gear / gimbal with an NEX.
3) So far I have stuck to the 1038 DJI props, as well as my friends I mentioned. But I know many other on this forum that will chime in and give you some good advice on that subject.

 

[Fanch]

Hi!

thanks for your answer.
Do you know what kind of downlink your friends are using?

 

[ProPilotWannaBe]

He is using a MONDO Stinger 5.8GHZ 500mw, wi an HDMI converter for the NEX-7. He uses a MKTR Professional landing gear.
I use the DJI 5.8GHz Tx on both my birds.

 

[Fanch]

Thanks!
I'll invest in some more 3S batteries and train a bit before I invest in skids / gimbal.
How much flying time do you get?

 

[ProPilotWannaBe]

I use 3S 6000mah on my F450+Gimbal+VTx+GoPro, and I get about 15-16 minutes of normal flying (i.e. not pushing the motors very hard). When I finish my F550 setup, I am hoping to still get 10-11 minutes, but probably less if I end up putting my NEX on it.

 

[Tahoe Ed]

I would start with a smaller battery than 6000mAh. I used 2650-3000 mAh 3S and now use 3000mAh 4S. This is not a heavy lift copter and the weight of these large lipos severely limit the performance of the craft. Remember that for the Naza to control attitude and altitude it needs some overhead on the motors. If you are at 90% just to fly you have very little left for control functions.

 

[Fanch]

Thanks Tahoe
I have a 4S 5000mAh. I have just been up a few times now. I will missed the info about number of S and size of props when I configured my F550 so I am now stuck with my big pack. I'll probably will go over to 3S since I want to put a gimbal and a NEX5 under it.

 

[bruce365]

Hi Fanch, 4S 5000mah battery is perfect for the DJI F550 do not go backwards by using 3S batteries. I use the 4S 5 amp lipos with stock motors and graupner 10" props, after a 10 to 11 minute flight the motors are just slightly warm to the touch ( about body temperature). My AUW is 2.45 kg. Gimbal, landing gear, gopro2, telemetry.
Regards - bruce

 

[Benjamin Kenobi]

Likewise I use 4S 5000mah lipos and motors/ESC come down cool. Much more power too.

 

[jaysbay]

Likewise I use 4S 5000mah lipos and motors/ESC come down cool. Much more power too.

I just built a dji flame wheel hex and I'm running the new naza v-2 with a 5000 mah .Im having a problem with wobble,any slight gust of wind and it starts the wobble thing.I have played with the gains from 100 - 170 and it seems to fly best at around 160.Any tips would be appreciated .Ben what frame are you using.
Johnny

 

[Fanch]

no wobble here, flew in gusty conditions this morning and she (it's a she, right?) flew just lovely.
How do you get 10-11 mn of flight time? I'll get just above 5 mn. I am in Intelligent Mode.

 

[Benjamin Kenobi]

My gains are really low like 130% I think. Pretty stable in the wind. I get 11mins with 4S 5000mah and 9" Graupners and just a GoPro underneath. It's the 4S lipo that I find gives the better efficiency over a 3S.

 

[Benjamin Kenobi]

I just built a dji flame wheel hex and I'm running the new naza v-2 with a 5000 mah .Im having a problem with wobble,any slight gust of wind and it starts the wobble thing.I have played with the gains from 100 - 170 and it seems to fly best at around 160.Any tips would be appreciated .Ben what frame are you using.
Johnny

I fly the F550 too, it's listed in my signature. Have you calibrated your compass properly?

 

[ProPilotWannaBe]

How do you get 10-11 mn of flight time? I'll get just above 5 mn. I am in Intelligent Mode.

Fanch, how much mah are you putting back into the battery after flying? The general rule is that up to 80% of the battery capacity is fine. Are you sure you're using the full battery potential?

 

[jaysbay]

Hope you guys can help me out,I just built a new 550 flame wheel,with a new naza v-2 board and i screwed things up by punching keys on my computer.I thought i was upgrading my firmware and now i have a cfg-err error that pops up.After looking up the error ,it says configuration/recalibrate tx.Now when i plug into the computer software I get nothing to work.When I unplug from the computer I get a fast blinking red light on my led.I need help please.I even somehow deleted the craft from my dx-8 tx after all of these problems i was having.Now what I think I need to do is to start all over from scratch.How could I delete the previous firmware and bring the board back to its original state,like it came from the factory.I will be the first to tell you guys i am the worst at programing anything.(I can fly though ).I had a guy at the local field help me set this up originally,but i am embarrassed to even ask him again for help,And I really need to start teaching myself.Any help would be a big help to me guys.
Johnny

 

[ProPilotWannaBe]

Jaysbay, I would recommend fixing your DX-8 transmitter first and get that configured and talking to your receiver. Among other things, you will get that cfg-err if the Naza is not receiving data from the receiver which requires the transmitter being powered on and talking to it. Start with that first and confirm your receiver is outputing the correct information to the Naza.

 

[jaysbay]

Jaysbay, I would recommend fixing your DX-8 transmitter first and get that configured and talking to your receiver. Among other things, you will get that cfg-err if the Naza is not receiving data from the receiver which requires the transmitter being powered on and talking to it. Start with that first and confirm your receiver is outputing the correct information to the Naza.

Thanks for the reply,I am going out of town for a week,Once I return I will have some time to play with it.Before I screwed up my TX ,I had these issues .It just seemed that the TX was not talking to the board when i had it hooked up to the assit program.Thank you for the reply.
Johnny