F450/Naza fun in the wind...

GGoodrum

Member
Yesterday I thought I'd see how my F450/gimbal setup worked in strong gusty winds. We have this condition in southern California right now called Santa Ana winds, where a high pressure system over Nevada sends winds in a southwestern direction towards LA, compressing, heating up and drying out the air as it goes up and then down the mountains. This pushes the temps, even at the beaches, up into the 80s, but it also means it is windy as all get out. Where I'm at, we easily get 25-30 mph gusts. In places closer to mountain passes, it can 2-3 times that.

Anyway, I had one heck of a time, trying to fly this little F450. Even at a not-so-svelte 4-1/2 lbs/2.1kg, it was being tossed around quite handily. I tried several times to get the gains dialed in, but frankly, it was just about impossible to tell whether I was getting oscillations or if it was just the severe gusts. The gimble did a surprisingly good job, but I was really having to yank it all over the place, just to keep it from taking off on me.


In any case, this test was of limited value, as I can't see ever trying to do a video shoot in these sorts of crazy winds. :)

-- Gary
 
Last edited by a moderator:

Bowley

Member
Awesome fun just to free fly in strong wind though, the F450/Naza combo handles the wind way better than i thought it would, it feels almost impervious to it, apart from a bit of oscillation.
 

mailman35

Member
i will have to agree, once the atti is adjusted and tweaked, the quad handles quite well :p no camera mount on the flamewheel thats quite a bit further down the road for me :p
 

ChrisG

Member
Im loving my FPV Naza/Flamewheel, I attended a heli funfly all weekend and it rained and blew!
Didnt stop the Naza :tennis:

Here's a screenshot from 400ft, Blowing 20knts at 6:30pm and about to start raining again.... the sky was angry as you will see.

Had to drop my atti gains to 75, vert to 135 to get it nicer in the wind.
 

Attachments

  • Tincan.jpg
    Tincan.jpg
    86.7 KB · Views: 292
  • IMG_0590.jpg
    IMG_0590.jpg
    145 KB · Views: 341

mailman35

Member
nice pic, how long did it take to get that high up?
also a question, i see you have the naza mounted on the top plate, is the quad more stable that way? i currently have mine mounted in the center of the bottom plate.
 

GGoodrum

Member
Yesterday the winds were less, but still a bit gusty. I decided to try the stock 10" props, but I'm really not too happy with them. I spent an hour making sure all four were perfectly balanced, but there's no way they are as smooth as the 11x5 Graupners. I'm guessing it has to do with the fact that the Graupners are a lot stiffer. The vibration isolators, on the mount, kept the vibes pretty much out of the video, but I can detect a slight lack of smoothness, at certain times, with the gusting.


The motors seem to run hotter with these props on as well. With the Graupners, the motors were warm, but not so bad that you couldn't leave your fingers on them. After this flight, it became too uncomfortable after 3-4 seconds. The ambient temp was 81F/27C. Next, I'm going to try my GWS 9x5x3 3-bladed props. On my other F450, these produce the smoothest performance. The Graupners won't work there, because it is a lot lighter setup, and the disc loading is too light for the 11x5s.

Eventually, when I get some Graupner 10x5s, I'll do some more comparison tests.

-- Gary
 
Last edited by a moderator:

ChrisG

Member
Thanks for the info Gary, I'm at 1320g and the 10x5 graupners are working a treat.
I just finished replacing all of the motor bearings with good Jap units, and made sure they were not to pre-loaded....everything is now running much smoother.
I always had 2 motors that ran hotter than the other 2 so I'm keen to see if this fixes that issue.

Mailman, does not take long at all to get high. It climbs much faster in Man mode too.
The pic is just a screenshot taken from my 1080hd gopro clip of the flight.
Not sure if mounting the Naza on the bottom plate would make any difference, make sure you have nothing rubbing or vibrating against it though.:tennis:
 

GGoodrum

Member
Thanks for the info Gary, I'm at 1320g and the 10x5 graupners are working a treat.
I just finished replacing all of the motor bearings with good Jap units, and made sure they were not to pre-loaded....everything is now running much smoother.
I always had 2 motors that ran hotter than the other 2 so I'm keen to see if this fixes that issue.

Mailman, does not take long at all to get high. It climbs much faster in Man mode too.
The pic is just a screenshot taken from my 1080hd gopro clip of the flight.
Not sure if mounting the Naza on the bottom plate would make any difference, make sure you have nothing rubbing or vibrating against it though.:tennis:

Changing to better bearings sounds like a good idea. What size are they? Time to put in an order to Boca. :)

Right now mine are all getting hot together, and they all have the same amount of cogging. My setup is pretty heavy, though, at 2.1kg/4-1/2 lbs.

-- Gary
 


ChrisG

Member
Hey Gary,
The bearings are 8x4x3mm, I managed to get some NTN units from a local "small parts" supplier.
Now they have new bearings that are also not too pre-loaded the motors spin more freely and when spun by hand with props on spin longer and stop with a bounce against the magnet poles rather than stopping abruptly as before.
I originally picked it up watching my FPV recordings and as I can see my front props I could see one stopping much faster than the other.

Bearings are fairly easy to replace Mailman,
- remove motor
- carefully remove the "C" clip and brass bush on the motor base (dont loose them, I have a big Magnet I do this over so it usually sticks to it rather than fly across my shop)
- slide motor apart.. will be hard as magnets keep it together.
- the bearings usually then fall out.. if not a gentle push will remove them
- Fit new bearings and re-assemble.:)

The sun is finally out here after 3 weeks of summer rain so im keen to get some more FPV flying done!! Loving it!
 

mailman35

Member
doh to me, i forgot to tighten all the prop nuts before i went out to fly tonight, and one flew off, i got the prop and no damage aside from a lost prop nut, anyone know where to get a replacement several from?
or what the thread size is on the shaft?

it seems like this is what i might need
Brass Nut for Spinners M8x1.25-M3
sadly hobbyking is out of them not to mention the amount of time it would take to get to the us. are there any reliable us sources for these parts?
 
Last edited by a moderator:

GGoodrum

Member
doh to me, i forgot to tighten all the prop nuts before i went out to fly tonight, and one flew off, i got the prop and no damage aside from a lost prop nut, anyone know where to get a replacement several from?
or what the thread size is on the shaft?

it seems like this is what i might need
Brass Nut for Spinners M8x1.25-M3
sadly hobbyking is out of them not to mention the amount of time it would take to get to the us. are there any reliable us sources for these parts?

Yes, that looks like the right one. You should be able to find those pretty easy, I would think.
 

GGoodrum

Member
Thanks, Chris, for the bearing info, and the magnet tip. :)

I just did another test flight , with the 9x5x3 props, and These are definitely the smoothest, so far. I took the time to really balance them and they are a ton quieter than the 10" stock props, and the motors were barely even warmer than ambient. I'm sticking with these, for sure. :)

-- Gary
 

mailman35

Member
actually i got a tip from someone on rcgroups that homedepot could have a replacement and what do you know they do, 6mmx1.0 threads the same. and stays on better then the stock.
and no wondering through a field looking for the lost nut :p
mark
 

ChrisG

Member
Looks like i'll have to get some of those props to try.. wonder if they will affect flight time?
I have some 4s packs too:)

I was about to post that they are M6 nuts... glad you got it flying again Mark.
 

mailman35

Member
flying again but one of my 2 batteries is showing a bad balance problem now, between 2 of the 3 cells, its a turningy 2650mah 40c and the differental between the cells is .020-.050 and its really bouncing around since ive had it hooked up to the balance checker, been charging it with a 1c charger, so its been taking a slow charge, and only running them to ~25% remaining. :( submitted an rma to hobbyking gonna ship it back tomorrow or the day after, got a better charger/balancer on the way. a thunder power TP610C-ACDC

edit
also stopped charging the pack and when i checked it this morning it was down to a .008 imbalance between cells 2-3
 
Last edited by a moderator:


GGoodrum

Member
Yes, anything can happen. :) I used to live in an area called Porter Ranch, in the northern SF Valley part of LA. We lived on a canyon that took a left turn, right at our house. The Santa Ana winds like we had here the other day (25-30mph...) would be more like 75-80mph up there. You pretty much had winds all the time, from October to March. We lost part of our hillside in heavy El Nino rains one year, and then had our original house burnt to the ground in a canyon fire in 1989 during a strong Santa Ana. We built a new house, to new building codes, after the fire, so we had a lot less structural damage during the Northridge earthquake in 1994, which had its epicenter 2 miles from our house, than our neighbors did, but it was still a mess. After that, we decided enough was enough. About all that was left was to wait for the locust to come over the hill, so we moved south, to Orange County. :)

Did another quick test yesterday, with the 9x5x3 GWS 3-bladed props. I balanced them first, and it is amazing how much quieter they are than either the 10" stock props, or the 11x5 Graupners. Also, the motors were barely above ambient (about 68F...). I guess maybe they like the faster rpm? I don't know what to think. I've never been a airplane guy, just helis, so this whole prop thing is fairly new to me. All I know is they seem to work best with this setup, with zero vibes.


The winds were pretty much down to our normal ocean breezes, which we have almost year-round, but there was a few big gusts, especially right at the end, where I just about lost it. The fact I even got it back down on the ground sort of impressed my 24-year old son, who normally has little faith in my flying abilities. :highly_amused:

Anyway, I'm sticking with these props, and I will also use them on my new DJI hex that I'm just finishing up.

-- Gary
 
Last edited by a moderator:


ChrisG

Member
They are the right size but you don't need to over do it, they are specialist s/steel units.
2 of those are more than a replacement motor :)

Theses are the ones similar spec to what I used... Much better than std.
http://www.bocabearings.com/bearing-inventory/Radial-Bearings/321/MR693ZZ-3x8x4

If you really want to go stainless you could use these, personally I have found no benifit using s/s bearings in brushless motors.
http://www.bocabearings.com/bearing-inventory/Radial-Bearings/1692/SMR693ZZ-3x8x4

Chris.
 

Top