[SOLVED] First Flight - My F450 can't lift of the ground - ArduCopter User Group

Splunkmeister . March 2, 2014 at 12:29pm

Nice setup. What mount did you use for your GPS? Can you please post a picture of the GPS mount?

Thomas > Splunkmeister . March 2, 2014 at 1:21pm

Hi Splunkmeister,

Here are some photos of my quad with this GPS mount. I buy it from GBL

https://picasaweb.google.com/104226316802060417563/F450#

Here are the link: http://www.goodluckbuy.com/gps-folding-antenna-mount-holder-for-mul...

This metal rod is antimagnetic afcourse as 3DR GPS have a compass.

Gary McCray March 2, 2014 at 12:08pm

Hi Thomas,

They definitely sold you incorrect pusher style props rather than correct puller or "tractor" style props.

And trust me 1045's are much better than 1038's for this copter.

I use 11" x 4.7 Carbon filled GemFan propellers that I have bored out to fit the DJI Motor hub and they are in my estimation perfect, but since they don't make a special DJI motor hubbed version I have to bore them out myself to fit.

The tractor style 1045 DJI props work fine however and when you get them get at least a full spare set or two during learning props are a disposable commodity.

For most props CW or CCW is a definition for either pusher or puller depending on motor rotation because the props can be simply reversed on the shaft, however for DJI taper broached motors / props this is not true.

For DJI tapered oval hub motors, DJI has tractor style props in CW and CCW (what you need) - - - and pusher style props in CW and CCW (what you have but do not need).

The airfoil is all wrong for flying with props upside down and they also bend excessively when trying to generate thrust in the wrong direction - they can easily generate less than half the thrust they can when they are "right" side up.

Which is why your motors really were straining at full throttle and you were barely able to get off the ground. (really easy to hear full throttle on your video - the motors were working great!)

And - like I said - If the cast in letters and numbers aren't on top, the props are upside down.

Gary McCray > Gary McCray March 2, 2014 at 12:31pm

Hi Thomas, Please look at my F330 with 8" props here which shows correct prop mounting, you can see correct curve and barely make out printing on top of left prop towards front. (you can zoom on this photo).

Also notice way prop curves up in middle down toward leading and trailing edge.

You can also check out props in my build article here: http://copter.ardupilot.com/wiki/dji-f330-flamewheel/

To get running, you can bore out your current propeller hubs just enough with a drill to get them to slip fit over your motor shafts the other way, tighten them down good though because they are no longer locked to shaft by the oval.

It will probably fly OK but I definitely recommend switching up to the correct tractor style 1045's in the long run.

Best Regards,

Gary
Thomas > Gary McCray March 2, 2014 at 1:15pm

Hi Gary,

I now see that my props are in wrong way (i was flying over a year on plane so i do not know how i did not notice that they are upside down - maybe becouse this oval). I look at them and the oval is almost thru the hole so with some push they will fit with correct position :) As i'm not confidence with multirotors for now i want to use plastic props rather the carbon fiber (i use carbons on my helis and the performance are great), need setup vibrations, then know how to use flying modes, carbon can be very dangerous. I will look for the 10x45 DJI props as You suggest and tomorrow i will try second fly hoply to the moon :)

And for last i still don't understand differents between all that pullers, pushers and trackers style of props, i wil try to find the info about it in my native language...

Thank You Gary for Your help and patience :)
Gary McCray > Thomas March 2, 2014 at 2:30pm

Hi Thomas,

The Gemfan Carbon Filled props I was recommending are not carbon fiber, but carbon filled plastic. they are tougher than ordinary plastic props but not as tough or brittle or sharp as Carbon fiber props.

And they only cost slightly more than straight plastic props (unlike very expensive carbon fiber props)

I also don't like carbon fiber props, especially for learning way too sharp and dangerous.

These are the DJI motor hub compatible GemFan Carbon Filled Props I was recommending although you can probably get them easier somewhere else. You would need 2 of each and they are correct puller - (TRACTOR) design (tractor as in farm tractor or truck tractor pulling trailer).

In the US a pusher prop is one where the prop is behind the motor like on a pusher plane whereas a puller or tractor prop is on the front of the plane / motor and is pulling the plane along (like a trailer).

http://www.rcdude.com/servlet/the-Propellers-cln-GemFan-Multi-dsh-R...

Although the correct 1045 DJI plastic props will also work fine.

If you are going to use the props you have now reversed, you might be be better off reaming them out a bit so that they don't warp when you fasten them down on the motor shaft.

Best Regards,

Gary
Thomas > Gary McCray March 3, 2014 at 8:02am

Hi, i have found one local RC store that have this props You suggest so as soon as they will be in stock i order them. Unfortunetly todays weather (rain and wind and cold) stops me to made second fly grrr... still is winter here... The props now is mounted proper way, not so much play and they sit quite tight, don't see any warp. As soon as weather will be ok i will go flying :)

R. D. Starwalt March 2, 2014 at 11:16am

Good catch Gary!

Letters on props go up.

-=Doug

Thomas > R. D. Starwalt March 2, 2014 at 11:20am

Ok i got it.. but they not fit in this way... The cuting is on the letter side, the motor shaft has also cutting so to put them on letters up i have to push them hard on the shaft... Is the right way to do it? Upside down they fit perfectly, they just go on the shaft smoothly...

Gary McCray March 2, 2014 at 9:47am

Hi Thomas,

YOUR PROPS ARE UPSIDE DOWN!

OK first off I am flying that exact copter with a 3S 4000mah battery.

APM 2.0, DJI F450 frame, DJI Motors, DJI Opto 30 AMP ESCs and DJI 10" Props, (Also with GemFan 11" carbon filled props)

You don't need 8" props or a 4 S battery, with the setup you have it should take off like a rocket (out of sight straight up in about 5 seconds).

Something else is wrong.

The Opto ESCs work fine without calibration out of the box both because they are precalibrated and because they can't be calibrated.

And stock DJI motors as supplied with DJI F450 ARF kit are plenty powerful.

Do you have props upside down, from looking at your picture very closely that looks like a strong possibility and would explain everything (as a matter of fact from looking at it closely I am virtually positive that is your problem).

Cast in printing on props must be on top.

Also if you look at your props you will notice that the prop is curved along it's length that curve needs to be such that it is highest in the middle and lowest on the leading and trailing edge in relation to the ground.

Yours aren't.

Turn over your props and watch this thing take off for the moon.

BTW, I love these little Flamewheels, they are superb flyers and very durable just exactly like you have it set up but with the props the other way around.

I'm going to amend the DJI F330 build wiki page I wrote here to emphasize making sure the props are right side up.

http://copter.ardupilot.com/wiki/dji-f330-flamewheel/

Best Regards,

Gary

ArduCopter User Group

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