F550 Props and props

[JLO]

Ok I have been flying and testing a F550 Naza, Lipo 4S 5400, FPV gear GoPro with housing, 10 minutes aprox and DJI 8' Props for a while not much complain, today I try my new Graupner 8.5 props and the bird gave me the same flight time the same warm motors pretty much the same except it was a little quiet but more jumpy unstable more inaccurate on the GPS hover and hold it could be the little wind I had I dont know..
my question is what are the distinct differences between flying with DJI props and the better ones like Graupner the DJI are more flexible and are wider they look like APC Slow Fly props the Graupner look more like the APC Thin Electric any thoughts on this??

also I understand that with 4S lipos the 8' props are better, and with 3S the 10'props are better is really true, if not what would I spec t to gain if I go to 10" Graupners

thanks

 

[Dewster]

I hear that DJI props are prone to breaking in mid flight. Ive seen video of this happening: YouTube video http://youtu.be/ifpiMJRZ7vo

There have been many who have complained about this on the forum and a few that say they do not have problems with the prop.

The Graupners are stiffer and I'm told more brittle if you have a crash.

I had some Gemfan full carbon fiber props. After placing them on my craft, I saw that the response was more snappier and crisp. Unfortunately I had one rotor snap on me with less than five minutes flight time. My flat Hex immediate tumbled, went into intelligent mode shut off (pitch exceeding 45 degrees. The tumble had my craft over 90 degrees...), and shut down the motors. Some say that I may have over tightened the prop nut, or that it was a freak occurances. Either way my craft was destroyed. The prop (10x4.5) has a thin hub especially when compared to the Graupners. I think it's a design flaw. Either way watch the torque on your nuts. Stiff props are less forgiving.

Believe it or not, the APC props gave me stable and smoothe flight. They flex under stress and can handle flight stress without self destructing. My craft wasn't as snappy, but I was flying a photo ship and didn't care for acrobatics.

My Hexa is now a quad since two motors were damaged in the crash. I use Avroto 2814/11s with APC 10x4.7 props. I had these motors on my XAircraft DIY Hexa with DJI 30 amp esc. I had no problem with warm motors or ESCs. My flight times with the weight of my craft was 4.5 minutes or 5 minutes without camera (using 6000 3 s lipo).

I currently have the four motors on a DJI F450 frame and get a solid 8 minute flight using APC props and a 6000 mah lipo. (yes overkill). My craft has no overheating issues from the motors or esc.

Outdoor cold temps affect props too. Too cold and a cheap prop will snap under stress.

Props seem to rank high as a cause for crashes. They all can break. Just some easier than others. I will stick with APC props. Graupner and Xoar props are getting consistently good reviews.

 

[JLO]

Thanks Dewster the brittleness vs the more flex makes sense also the hub diameter very important I am going to try 8' APC any suggestion on 8x?
and the question can the stock DJI handle 10" props with 4S batteries
thanks

 

[hjls3]

Ok I have been flying and testing a F550 Naza, Lipo 4S 5400, FPV gear GoPro with housing, 10 minutes aprox and DJI 8' Props for a while not much complain,

I have had fantastic luck with the DJI 8" props. From what I can tell it is the 10" props that seem to make for most the problems. I have 2 550's and one does use 11" Graupner props (extensions, 4s and AXI motor). While the two ships really are not comparable, I have noticed that the DJI 8 inch seems to take quite a bit more abuse. I am a bit curious though...if you liked the way the DJI props worked and flight times were decent, why are you switching? Is it because of reading about all the DJI prop failures? I really do think those were mostly 10" DJI props that come on the 450. I have recently learned that messing with a setup that I like because I want the latest and greatest, isnt always the best thing todo. It is currently costing me quite a few bucks . Anyways Just throwing that out there and wish you the best of luck.

 

[araines2750]

I asked my DJI Dealer about this a while back and he indicated that he preferred the 10" props, as Do I. This makes for a much more stable platform for non-sport flying.
I fly 4S 5000 with 12-14 min. flight time with 10" stock DJI props. I could actually go longer, but do not go below 85% on my Lipos.
Also, I asked about the breakage issue with DJI props and was advised that the old prop failure problem had been solved with a redesign of the props. The new ones have a larger hub to prevent breakage. He indicated since the redesign he has had no breakage complaints. My motors are warmer with 4S than 3S but not where near "hot" or hot enough to cause damage.
This is my experience. I hope it helps.

 

[JLO]

Originally Posted by hjls3

why are you switching? Is it because of reading about all the DJI prop failures? I really do think those were mostly 10" DJI props that come on the 450. I have recently learned that messing with a setup that I like because I want the latest and greatest, isnt always the best thing todo. It is currently costing me quite a few bucks . Anyways Just throwing that out there and wish you the best of luck.


You are totally right I have gotten caried away with wanting the greatest and latest and have gotten influence reading on the posts and of course sepend more $$$, at least most props are not that expensive except for a few hi tech ones like CF the rest, DJI, APC, even Graupners to a point, it doesn't hurt to have several sets to try, test and learn, for me, I am on my way to use this cool hobby for video and if I ever make any $ the trial and error is worth it.

 

[JLO]

Ok guys I flew 2 flights today 4S 5400 lipo F550 full FPV, GoPro cam with housing GPS Craft weight 5.50 LBS, slight wind

1 flight Graupners 8.5 props very nice, a little responsive drifted a little on GPS hover, again a little jumpy hmmmmm it look not so good for video
motors warm ESC's warm 10 minutes flight 16% left on the lipo

waited about 10 minutes between flights in South florida sun 89*F at about noon time

2 Flight DJI 10' props other components same as 1 flight...... NIce Nice Nice very stable no drift on GPS it look very good for video
motors.. pretty HOT ESC's warm 10 minutes flight 20% left on the lipo
So te question is how hot is too hot on the DJI motors
is there a good portable gadget to measure motor temperature.....
any thoughts
I guess I should let the motors cool a little more between flights
thanks

 

[araines2750]

This is just my OPINION.
Motors are OK when warm to the point that you can hold them in your hand and feel the warmth, but not so hot that it is uncomfortable to the point you must let go.
If they are hot beyond that, I would say too hot.

I always give the motors time to cool between flights. About 10 min. and they are cool to the touch.
I would gladly yield to someone with a different opinion.
I hope this helps.

 

[goraplx]

Ok guys I flew 2 flights today 4S 5400 lipo F550 full FPV, GoPro cam with housing GPS Craft weight 5.50 LBS, slight wind

1 flight Graupners 8.5 props very nice, a little responsive drifted a little on GPS hover, again a little jumpy hmmmmm it look not so good for video
motors warm ESC's warm 10 minutes flight 16% left on the lipo

waited about 10 minutes between flights in South florida sun 89*F at about noon time

2 Flight DJI 10' props other components same as 1 flight...... NIce Nice Nice very stable no drift on GPS it look very good for video
motors.. pretty HOT ESC's warm 10 minutes flight 20% left on the lipo
So te question is how hot is too hot on the DJI motors
is there a good portable gadget to measure motor temperature.....
any thoughts
I guess I should let the motors cool a little more between flights
thanks

Ir pen Infrared digital thermometer : eBay

 

[hjls3]

2 Flight DJI 10' props other components same as 1 flight...... NIce Nice Nice very stable no drift on GPS it look very good for video
motors..

JLO so you think the 10" DJI props were considerably more stable than the 8" DJI? How much did you change your gains? Of course I am the guy saying leave well enough alone but as cheap as those props are, if they are way more stable...maybe id give it a go.

 

[goraplx]

From my exp. I preffered 8" than 10" props. My f550 was more stable with 8". I think more rpm better. Then i decided to buy 9" graupners and im v.happy now.I use 3s lipo only.

 

[JLO]

Ok I flew again this afternoon more questions after watching the video from the gopro the footage look kind of wabbly even when I was flying forward, hmmmm I use again the DJI 10 props my gains...well I have not mess with them the are the default ones, also I had GPS ON all the time perhaps it over corrects and makes the wobble.
Motors where hot again

 

[goraplx]

my perfect gains are 250%, 250%, 140%, 160%
and attitude gains : 117% , 117%

My F550 wasnt stable on 10" like i said before , maybe not enough rpm.. I'm comparing it to the heli , flying better when more rpm

No wobbling at all. Increase pitch and roll. Dont know why people changing gains between 100-170% if visible effect starts from 200%-300% Weight 1.3kg -1.4kg

 

[JLO]

Ok today I fly again same set up as before 10" DJI props but this time I check and balance my 6 props and better balance the craft so all the motors work kind the same also this time I play with the gains from 100 on roll and pitch to 200 I did not see much difference still some wobble I will try the settings of "goraplix" tomorrow I did notice the shakiness when I lower the gains bellow 100 so I got me thinking
Q.. do the gains have a big relasionship with the all arownd weight of the craft more weight more gain

 

[goraplx]

i think you use same gain on pitch and roll simultaneously. like if pitch 220 roll will be same. Are you able to record any movie.. ?