Prop Calc and DJI Stock Motors

R

Romaja

Guest
I am trying to input data into propcalc and get hung up on motor selection. It appears every possible motor selection is available except the stock DJI 920kv motors? I cant seem to find the required data on these motors to input it manually either.
I wanted to compare the performance of my F450 stock setup to some Tiger motors but unable to get sufficient DJI motor data to input?

Anybody? Thanks
 


helloman1976

Ziptie Relocation Expert
I am trying to input data into propcalc and get hung up on motor selection. It appears every possible motor selection is available except the stock DJI 920kv motors? I cant seem to find the required data on these motors to input it manually either.
I wanted to compare the performance of my F450 stock setup to some Tiger motors but unable to get sufficient DJI motor data to input?

Anybody? Thanks


My first question is why change the motors? Keep them, use the 10"x3 new DJI props on 4S and you'll be happy as a hog. Second input is the prop calc is not for multirotors and you won't get accurate data from that, it's for airplanes. Multirotors fly more like helicopters so they are basically in a constant state of hover versus an airplane where they are moving forward making the prop much more efficient. If you want prop data for a multi-rotor use the eCalc multi-rotor website. http://www.ecalc.ch/xcoptercalc.htm?ecalc&lang=en

I don't know the DJI motor data other than they are likely something like this.
http://hobbyking.com/hobbyking/stor...s_28_30S_900kv_270w_short_shaft_version_.html

Hope that helps.
 

R

Romaja

Guest
Thanks for your reply. I used your link for eCalc multirotor website and still does not list DJI under motors? Im curious as to why it would not be listed as DJI Motors are abundant and popular. I am currently running 3S 3300 batteries and Gem Fan 1045 props. I might take your advice and step up to 4S and those 10 x 3 props you recommended.

Thanks
 

helloman1976

Ziptie Relocation Expert
Thanks for your reply. I used your link for eCalc multirotor website and still does not list DJI under motors? Im curious as to why it would not be listed as DJI Motors are abundant and popular. I am currently running 3S 3300 batteries and Gem Fan 1045 props. I might take your advice and step up to 4S and those 10 x 3 props you recommended.

Thanks

I sent you a link on some 900Kv motors, use the information from that only input 920Kv instead. I hear 4S on the 10x3.8 props from DJI works very well and gives you good flight time. There are going to be quite a few people who disagree with me on this but Gemfan props in my personal opinion are garbage. The new DJI 10x3.8 for those high speed 920Kv DJI motors I hear are excellent.
 

R

Romaja

Guest
Thanks again,
I will use the data you provided. I have some 10 x 5 Gem Fan carbon fiber Graupner style coming soon. I will give those a try on my 3S batteries.
 

helloman1976

Ziptie Relocation Expert
Thanks again,
I will use the data you provided. I have some 10 x 5 Gem Fan carbon fiber Graupner style coming soon. I will give those a try on my 3S batteries.


No problem, the Graupner 10x5 style carbon fibers for sure need to be on 3S with the 920Kv motors. The higher speed motors won't like the deeper pitch props on 4S and they'll get hot. You can get away with 10x3 DJI style props on 4S though. Since you already have 3S batteries you can stick with those to save some money :) I personally prefer lower KV motors with bigger props on 4S because of the increased flight time and higher voltage efficiency plus less heat on my parts etc.
 

R

Romaja

Guest
Thanks,
I would like to built up an FPV rig. Still have a lot to learn about prop/engine/batt combos. I was looking at the Tiger 2216-11 900kv but need more research. Also, I live in the Northwest and have a dozen fir trees that extend 100 feet. Thinking I might not have the coverage I needed for FPV flight from home. Not to mention the return to home feature is lower than my trees (RTH= 20 meters/65 feet)..yikes. I learned on a Heli-max sq1 but is too small now. I was wondering if I built up a F330 if it would be significantly more nimble than my F450 when flying on my 1/2 acre lot with enormous trees?

Futaba 8TFGH
Flame wheel 450 kit
Turnigy 3S3300 mHa batteries
890 Grams AUW
 

helloman1976

Ziptie Relocation Expert
Thanks,
I would like to built up an FPV rig. Still have a lot to learn about prop/engine/batt combos. I was looking at the Tiger 2216-11 900kv but need more research. Also, I live in the Northwest and have a dozen fir trees that extend 100 feet. Thinking I might not have the coverage I needed for FPV flight from home. Not to mention the return to home feature is lower than my trees (RTH= 20 meters/65 feet)..yikes. I learned on a Heli-max sq1 but is too small now. I was wondering if I built up a F330 if it would be significantly more nimble than my F450 when flying on my 1/2 acre lot with enormous trees?

Futaba 8TFGH
Flame wheel 450 kit
Turnigy 3S3300 mHa batteries
890 Grams AUW


They are very good motors no doubt however, the Sunnysky motors are superior in build quality given the tests I've seen that record how balanced the motors are which I personally assume results in build quality not to mention they are cheaper. I don't see a reason to change motors if you are using the DJI motors which are solid motors too, can you explain why you want to do that?

You may not have enough coverage to fly on your land in what regards? Video? Transmitter? Any of those things can be overcame and I can help you with that if you let me know what you have now and/or what exactly you are up against aside from some trees. For example, the lower the frequency you use for video the better penetration it'll have and UHF for your radio won't have any issues at all.

Keep in mind the Naza return to home feature is only 20 meters if you are flying below 20 meters when you lose radio signal. If you are flying above that then it will return to home at whatever altitude you were last at and only after it's hovered for a bit while you try to re-establish communication.

Your F450 will be PLENTY nimble for FPV or sport flying, you don't need to build an F330 unless you are looking for something really wild. Your F450 with 8" or 9" props on 4S should be plenty wild enough for FPV and honestly you don't really want that unless that's your entire purpose. check out my videos, that was done with an F550 and for me at least that's wild enough :) I flew my F550 through the woods many times with no issues in dodging trees and obstacles.
 

R

Romaja

Guest
Helloman 1976,

I will try to be more clear in writings. Built up a F450 from the kit a month ago. Very addictive! No FPV yet. Had to learn how to solder Bla bla....
I recently retired early from the airlines and have been fascinated with the technology as it pertains to Multicopters. The systems I have been using on the big jets is much the same as the multicopter controllers ( gps, gyros, barometer etc.) That said, I am used to sitting inside the craft which is a different orientation than RC flying especially the longitudinal axis or rolling moment. I am by no means an expert. I have been practicing flying in manual mode since that seems to be the most challenging.

My 8TFGH transmitter, I have -20 expo ailerons and elevator with dual rate dialed down to 80. This helps as it is very sensitive especially introducing a little up elevator in higher speed flight. Rears up like a horse when you pull back on the reins. Practice I guess. Must have 50 cycles on the batteries and have hugged a few bushes but able to stop the props (CSC manuever) quick enough to not incur any damage. Broke my first prop the other day plus one of the legs as I lost orientation and slowly drifted into a 100 foot fir tree. All in all pretty tough bird!.

As mentioned in a earlier post I have lots of tall trees when I fly at home and the F450 is a bit of a beast in close quarters swinging 10" props. I was wondering if the DJI 330mm frame be noticeably more agile and nimble in the tighter environments for non fpv or if its worth it?


The only knowledge I have concerning FPV systems is what I have garnered from this website which has been very helpful.

Lots to learn about FPV before taking the plunge. As mentioned I would like to fly FPV from my home which is a treed (100 footers) .5 acre lot but want to do it right and be safe. I need to learn what fpv systems play nice with each other and if reception will be adequate to accomplish this. Also, I would like to shoot video of the many scenic places the Northwest has to offer (Oregon Coast etc.). I think I will get my Ham radio license as well.

My plan is to immerse myself slowly into this hobby and keep flying non fpv until late summer or early fall and then build up an FPV rig. When the time comes your recommendations on equipment would be helpful.

Kind Regards
 

helloman1976

Ziptie Relocation Expert
Ok that clears things up, still not sure on the reason for the motor swap outs though but I completely get the rest and welcome to the addiction, I also have it BADDDD.

Since you said it's hard to control your 450 and you have negative expo on it I'm curious why you'd want to go to a smaller more nimble craft? If you want to fly fast and dodge trees the QAV500 or the ever famous TBS Discovery Quad is the way to go hands down and you can convert you 450 to a TBS quad which I believe is how most people end up with one. Going to the 330 is probably a bad idea honestly as there are better choices like the later which you'd really enjoy a lot more I think. Generally speaking, much like with aircraft, the bigger it is the more stable it is and vice-versa is true. If you want to film you'll need stable, if you want to dodge trees you'll need small, light and fast so the two are counter to each other but there is middle ground and I'd be more than happy to help you find it. I started with the DJI F550 which I built from hobbyking and it was the knock-off kit. I picked all the parts separately which I personally prefer because it saves you money as well as it's super fun, for me at least, to build.

Better than learning to fly line-of-sight and then switching to FPV is to go straight into FPV and start in GPS mode or attitude mode which ever you prefer. Flying line-of-sight is nothing like flying FPV and if you want to learn FPV without risking your craft get a computer simulator you can hook your 8FG to and learn like that. Something like the PhoenixRc HD 1080p Version 4 simulator is invaluable and you can use it for learning to fly anything pretty much. There are other cheaper versions out there too like the AeroSim RC simulator, I put links to both on YouTube so you can see them in action. The only thing I'd say is make sure you can hook your controller up to them so you can learn on the same controller. I used a flight simulator and I still do to practice and it's almost 5 years old now so they really are worth it and help tremendously on honing your skills.

http://www.youtube.com/watch?v=AAuYGbjDpcQ
http://www.youtube.com/watch?v=9gCi8Qz9VD8

As far as radio and video goes if you have a lot of obstacles you're going to have to go with low frequency everything. UHF radio and 900Mhz or 1.3Ghz video and when you go to get those we can address the issues with each and using both together. I'm sure you know a little bit about radios and frequencies already but the basic idea is the lower the frequency the less power you need to go the same distance as a higher frequency and the better the penetration. For example, 5.8Ghz takes more power to go 1 mile then 900Mhz does and 5.8Ghz will not penetrate anything very well at all so flying around trees...no way but we'll get into that later because there's a lot more to it.

As far as flying in the trees goes, I'd say you're going to have to step up and be ready to fly above them and be ok with that knowing and accepting the risks if you're going to fly on your own land. But again, the best way to learn FPV is to do it or do it in a flight simulator. Flying in a big open park with nobody around is the way to go once you are comfortable.

Side note, I grew up in Oregon in the Eugene and Roseburg areas and I know the coast area well. I went out there not to long ago to visit my parents but couldn't take my multicopter because it wasn't finished yet but that area is going to be spectacular to film. The biggest issue you're going to run into in filming and flying out there is the insane wind which MR's do not like much at all, they get blown around easy. :)
 

R

Romaja

Guest
Ok that clears things up, still not sure on the reason for the motor swap outs though but I completely get the rest and welcome to the addiction, I also have it BADDDD.

Since you said it's hard to control your 450 and you have negative expo on it I'm curious why you'd want to go to a smaller more nimble craft? If you want to fly fast and dodge trees the QAV500 or the ever famous TBS Discovery Quad is the way to go hands down and you can convert you 450 to a TBS quad which I believe is how most people end up with one. Going to the 330 is probably a bad idea honestly as there are better choices like the later which you'd really enjoy a lot more I think. Generally speaking, much like with aircraft, the bigger it is the more stable it is and vice-versa is true. If you want to film you'll need stable, if you want to dodge trees you'll need small, light and fast so the two are counter to each other but there is middle ground and I'd be more than happy to help you find it. I started with the DJI F550 which I built from hobbyking and it was the knock-off kit. I picked all the parts separately which I personally prefer because it saves you money as well as it's super fun, for me at least, to build.

Better than learning to fly line-of-sight and then switching to FPV is to go straight into FPV and start in GPS mode or attitude mode which ever you prefer. Flying line-of-sight is nothing like flying FPV and if you want to learn FPV without risking your craft get a computer simulator you can hook your 8FG to and learn like that. Something like the PhoenixRc HD 1080p Version 4 simulator is invaluable and you can use it for learning to fly anything pretty much. There are other cheaper versions out there too like the AeroSim RC simulator, I put links to both on YouTube so you can see them in action. The only thing I'd say is make sure you can hook your controller up to them so you can learn on the same controller. I used a flight simulator and I still do to practice and it's almost 5 years old now so they really are worth it and help tremendously on honing your skills.

http://www.youtube.com/watch?v=AAuYGbjDpcQ
http://www.youtube.com/watch?v=9gCi8Qz9VD8

As far as radio and video goes if you have a lot of obstacles you're going to have to go with low frequency everything. UHF radio and 900Mhz or 1.3Ghz video and when you go to get those we can address the issues with each and using both together. I'm sure you know a little bit about radios and frequencies already but the basic idea is the lower the frequency the less power you need to go the same distance as a higher frequency and the better the penetration. For example, 5.8Ghz takes more power to go 1 mile then 900Mhz does and 5.8Ghz will not penetrate anything very well at all so flying around trees...no way but we'll get into that later because there's a lot more to it.

As far as flying in the trees goes, I'd say you're going to have to step up and be ready to fly above them and be ok with that knowing and accepting the risks if you're going to fly on your own land. But again, the best way to learn FPV is to do it or do it in a flight simulator. Flying in a big open park with nobody around is the way to go once you are comfortable.

Side note, I grew up in Oregon in the Eugene and Roseburg areas and I know the coast area well. I went out there not to long ago to visit my parents but couldn't take my multicopter because it wasn't finished yet but that area is going to be spectacular to film. The biggest issue you're going to run into in filming and flying out there is the insane wind which MR's do not like much at all, they get blown around easy. :)



I would like a more nimble craft for flying at home in close quarters. Also, for travel as it would be more transportable. I think I will need 2 different quads as my missions would be in direct conflict. Probably build up a 330mm size soon w/ DJI motors for commonality and build an FPV rig later this year with different motors (TBS Frame sounds good).

Havent read much on UHF yet and it sounds like lower frequency will be what I need for FPV in my environment when the time comes.

Looked at the videos on simulators you recommended. I am an Apple guy and currently have an Imac 24 so I would have to buy windows program and put on my Mac as Macs OS are not fully supported. I had a great planes sim a few years ago and flew it from the cockpit and seemed to do fine.

Although it really wasnt FPV as this is a newer thing to sims and most likely much more realistic now to real FPV flight.

I was looking at Tiger motors for a TBS frame eventually as I thought they might be more efficient than the DJI's and maybe less vibration and longer run times. The pancakes look promising from the vibration standpoint (the moment being closer to the arms). Looks like a lot of people are happy with a the Tiger 2216-11 with 9 inch Graups. I have a generous budget as this stuff is expensive. That said, I dont need to waist money if there is no reason to. The Sunny Sky motors you suggested would be a consideration.

I have tall trees as mentioned and was concerned about RTH driving through but as you reminded me that if the RTH is triggered it will not descend to 20 meters if above that. So I will fly above tree height and be fine with that.

Sounds like you are familiar with Oregon State and the many photo/video opportunities.
 

helloman1976

Ziptie Relocation Expert
Personally, I'd go straight to the TBS discovery if you are considering the 330 and you already have the budget. I'd skip the 330 and keep your 450 for later because once you get your TBS you'll probably never touch it again. If you haven't already check out some videos on YouTube of the TBS discovery and I think you'll see that it can easily be a fast flying, tree dodging nimble MR. The Tiger motors will have less vibration but if you check out the YouTube videos you'll see that the Sunnysky motors have even less and are half the price. As far as efficiency goes they will all be so close that it'll be unnoticeable. I spend $15 per motor on Turnigy NTM 750KV motors from hobbyking with no issues as all, they aren't the best but they aren't $50 each.

UHF is where it's at if you want range, you really can't get much better than that at this point. I've seen people go as far as 60Km and as close as 10 km but be behind buildings so it works very, very well. EzUHF is what everyone raves about. I'm working on getting one very soon, maybe this week but they are sold out almost all the time as they are super popular.

I flew my Y6 today, I hit the throttle and realized that I had not calibrated the ESCs...oopps...it tipped to one side but I was able to recover it :) Even the pros make mistakes.

 
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R

Romaja

Guest
Personally, I'd go straight to the TBS discovery if you are considering the 330 and you already have the budget. I'd skip the 330 and keep your 450 for later because once you get your TBS you'll probably never touch it again. If you haven't already check out some videos on YouTube of the TBS discovery and I think you'll see that it can easily be a fast flying, tree dodging nimble MR. The Tiger motors will have less vibration but if you check out the YouTube videos you'll see that the Sunnysky motors have even less and are half the price. As far as efficiency goes they will all be so close that it'll be unnoticeable. I spend $15 per motor on Turnigy NTM 750KV motors from hobbyking with no issues as all, they aren't the best but they aren't $50 each.

UHF is where it's at if you want range, you really can't get much better than that at this point. I've seen people go as far as 60Km and as close as 10 km but be behind buildings so it works very, very well. EzUHF is what everyone raves about. I'm working on getting one very soon, maybe this week but they are sold out almost all the time as they are super popular.

I flew my Y6 today, I hit the throttle and realized that I had not calibrated the ESCs...oopps...it tipped to one side but I was able to recover it :) Even the pros make mistakes.



Looked at your video. Nice Y6 build. Looks like the level of redundancy is such that loosing a motor is not a big deal as opposed to a quad.

You might have a point on my next build, I could skip the F330 and just go right to the TBS. I already own the F450 and if I built up the F330 and the TBS I would have to buy 2 more Naza M's and GPS's which cost more $$$.

Still new to the whole MC thing and I am apprehensive about building the TBS since it will have a whole bunch more electronics on it. I havent found much in the way of the best mounting locations for various parts. Lots of binding of different parts. The soldering has come along and not horrible.

My fear is acquiring all the parts for an FPV craft and having problems with range,binding,additional wires and servo cords, etc..This would take the fun out of the build. I read the forums and they become a sort of triage for problems and you see mostly the small % of people that have had problems. I read where some people have has OSD's and the altitude and/or airspeed wont read correctly not necessarily the ezOSD. That would drive me nuts!!!

The ezUHF stuff looks very interesting especially the ground station and telemitry along with the google map/locator stuff. I wish the ezOSD had an attitude indicated as I am used to using one. Not a big deal and you could use the negative or positive symbol in front of the altimeter to detect a trend of climbing or decending.
 
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helloman1976

Ziptie Relocation Expert
It's like anything technology based, you're going to be working through constant issues dialing everything in to work together. Once you get it all dialed in you get to fly it until you crash it and then, you get to do it all over again. If you have a good knowledge of electronics and are good with a soldering iron don't fear the TBS build and you don't have to do it their way, you can do it your own. True there is very little space on there but there are also more build videos for the TBS out there than anything else so you can always seek knowledge from YouTube. Watch a bunch of YouTube TBS discovery build videos and store all those ideas in your head before you even buy the kit. Design it mentally and then when you are ready buy it and build it. In the meantime keep flying your F450 you already put money into, you can rip through trees with those or just fly high and stay close. You really need an open area to practice in and it's worth driving there.

I use the Eagle Tree OSD Pro everything including tracking ground station and I love it. You can customize the entire screen to be whatever you want. I have speed over ground, altitude by barometer within 1 foot, gps coordinates, G-force meter, magnetic heading, air temp, distance from home, direction to home, voltage, amperage, wattage and total mah used. The Eagle Tree OSD will even talk to you, "Low Battery" or whatever you want. I highly recommend Eagle Tree as they are the best in my opinion. I have the 150A eLogger and I record my flight data and I can export it out to Google Maps or to a program that I can analyze the flight data with, invaluable. This hobby is incredible and highly addictive lol

The EzUHF is the way to go for UHF from what I understand but I don't own one yet. That's what I've read on every board and every forum on MR's. I'll be getting on this week most likely.
 

R

Romaja

Guest
It's like anything technology based, you're going to be working through constant issues dialing everything in to work together. Once you get it all dialed in you get to fly it until you crash it and then, you get to do it all over again. If you have a good knowledge of electronics and are good with a soldering iron don't fear the TBS build and you don't have to do it their way, you can do it your own. True there is very little space on there but there are also more build videos for the TBS out there than anything else so you can always seek knowledge from YouTube. Watch a bunch of YouTube TBS discovery build videos and store all those ideas in your head before you even buy the kit. Design it mentally and then when you are ready buy it and build it. In the meantime keep flying your F450 you already put money into, you can rip through trees with those or just fly high and stay close. You really need an open area to practice in and it's worth driving there.

I use the Eagle Tree OSD Pro everything including tracking ground station and I love it. You can customize the entire screen to be whatever you want. I have speed over ground, altitude by barometer within 1 foot, gps coordinates, G-force meter, magnetic heading, air temp, distance from home, direction to home, voltage, amperage, wattage and total mah used. The Eagle Tree OSD will even talk to you, "Low Battery" or whatever you want. I highly recommend Eagle Tree as they are the best in my opinion. I have the 150A eLogger and I record my flight data and I can export it out to Google Maps or to a program that I can analyze the flight data with, invaluable. This hobby is incredible and highly addictive lol

The EzUHF is the way to go for UHF from what I understand but I don't own one yet. That's what I've read on every board and every forum on MR's. I'll be getting on this week most likely.

You brought up some good points. I looked at some TBS videos. Lots of nice builds and a good way to get ideas. Eagle Tree OSD looks like a nice setup and is highly customizable as mentioned. I wonder if the downloadable flight data includes signal strength? I have been practicing in an open field by my house with my F450. I downloaded the software update for the Naza V2 it seems to work well. I think I will build the TBS late summer and early fall. Meanwhile I will practice honing my skills and continue researching etc. Let me know how you like your ezUHF.

Regards
 

Will anybody EVER answer this question Please Please Please
e-calc
motor [h=1]DJI Motor 2212 920kv[/h] WHAT SETINGS DO YOU ENTER

considering that probably more of these motors have been sold than any other motor in the world getting the numbers for e-calc would be easy
instead it is easier to find rocking horse sh**t
EVERYONE AVOIDS ANSWERING THIS SIMPLE QUESTION!!!!!!!!!!!!!!!!!
I have seen hundreds of requests for this but NOT one CORRECT ANSWER showing how to get dji specs into e-calc correctly
 
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AirPix

Member
As a good approximation, I use motor data from Scorpion motors, readily available from their website. In this application, I'd use the Scorpion SII-2212-960 (and chances are it's the same motor, just rebadged).

Otherwise, you need to bug DJI about the specs to their motors. ;)

--Bill
 

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