Today my f450 wookong qaud crashed. Thank god it was only at 10m height. But I had a 8" dji prop snap on me. Today it was 13 degrees celcius so it wasn't het cold. I now ordered me some grauner 8x5 props. But pls be adviced don't use the dji props to many reports of them braking in the air.
don't use DJI props they snap 8"
- Thread starter rwijnhov
- Start date
DucktileMedia
Drone Enthusiast
I'm telling you they are made in the same factory as those Xaircraft props. I think I got a good pair but I wouldnt fly them either if I cared about my heli at all.
RCNut
Member
I had one DJI 8" prop that broke a blade at the hub after I cartwheeled it in its early days, but after replacing that one one prop and checking the others thoroughly for stress or damage Ive since had about 30 flights without problems. Can any of you with broken props link possible stress damage to a previous incident?
+3. My stock props have been through a lot. I inspect them frequently and have yet to see any problems, let alone any that developed on their own or from use. I've broken 2 during a crash in freezing temperatures. I balance all of my props, and actually like the stock 8" DJIs quite a bit.
You guys have got me wondering if I had one break on my last Friday. I was flying FPV and up pretty high and the quad flipped and fell to the ground. The prop nut was missing as well as the prop so I just assumed the nut came loose. I know they were tight and couldn't figure out how it came loose since I haven't had a prop come loose in the 15+ years I have been flying planes, including 4 strokes notorious for throwing props. If the prop broke at the hub then the nut would have probably came off too. I do have a way to find out though. I heard something hit the roof of the house and drop into the gutter right after the crash. I saw the prop nut in the video going the opposite way so it has to be the prop or part of it. I need fly over the roof and see if I can spot it. 
RCNut
Member
Hi Rcmike
Was the prop nut that came off from a clockwise prop? Most prop nuts tighten clockwise because they're designed for standard aircraft propellers that spin CCW. A CCW spinning prop acts to tighten the prop nut but a clockwise prop can loosen it especially during the startup or during a sudden speed change. It pays to check your CW prop nuts regularly for this. Ive only ever heard of prop nuts coming off on multirotors. It's extremely rare on fixed wing aircraft.
Ian
Was the prop nut that came off from a clockwise prop? Most prop nuts tighten clockwise because they're designed for standard aircraft propellers that spin CCW. A CCW spinning prop acts to tighten the prop nut but a clockwise prop can loosen it especially during the startup or during a sudden speed change. It pays to check your CW prop nuts regularly for this. Ive only ever heard of prop nuts coming off on multirotors. It's extremely rare on fixed wing aircraft.
Ian
You guys have got me wondering if I had one break on my last Friday. I was flying FPV and up pretty high and the quad flipped and fell to the ground. The prop nut was missing as well as the prop so I just assumed the nut came loose. I know they were tight and couldn't figure out how it came loose since I haven't had a prop come loose in the 15+ years I have been flying planes, including 4 strokes notorious for throwing props. If the prop broke at the hub then the nut would have probably came off too. I do have a way to find out though. I heard something hit the roof of the house and drop into the gutter right after the crash. I saw the prop nut in the video going the opposite way so it has to be the prop or part of it. I need fly over the roof and see if I can spot it.
hjls3
Member
So being new to this hobby I might be completely wrong but I cant help but wonder...Do props have a lifespan? Seems life 60 flights is alot of flights. I suppose there are lots of factors to be considered but being that the props arent that expensive (compared to replacing the whole kopter due to wreck) maybe I should replace my props every couple months...
I'm really not 100% sure which way it was spinning. I thought of that as well. It probably just came loose, I'll have to check the roof.
I know the other nuts are very tight. I changed around a couple of motors a few minutes ago and could barely get the nuts loose. I was afraid I was going to bend or break the props despite being very careful how I grabbed them.View attachment 3199View attachment 3198
I just switched my DJI 8" props on my F550 hexa to 8" Graupners. I used a step drill to make the hole 8mm. Just an FYI, the top hole is 5mm and the bottom is a shade less that 8mm. I set the drill press to stop at the top of the 8mm step. When I mounted the props, they were very tight. However, the mounting nuts were sufficient to make them flush with the bottom of the DJI motor mount. I like this in that they are flush and centered with the original Graupner moulded hole. I flew it this evening in a 10x10 area between two buildings with winds at 20mph and gusts. At times the hexa was tilted over 10 degrees to fight the wind. It was fun in a weird sort of way to try and get it to hover in such a small area. I will say that the Graupners were more efficient that the DJI props. I got an extra 2 mins before the second level of the battery monitor kicked in. That would give me about 20% more flying time or about 10mins. I am happy with that. I will reserve full endorsement until I can at least test them within the parameters specified by DJI, i.e., 17mph.
P.S. The 1/3 hp drill press with keyless chuck was $80 at Harbor Freight and the step drill was $13.
I just switched my DJI 8" props on my F550 hexa to 8" Graupners. I used a step drill to make the hole 8mm. Just an FYI, the top hole is 5mm and the bottom is a shade less that 8mm. I set the drill press to stop at the top of the 8mm step. When I mounted the props, they were very tight. However, the mounting nuts were sufficient to make them flush with the bottom of the DJI motor mount. I like this in that they are flush and centered with the original Graupner moulded hole. I flew it this evening in a 10x10 area between two buildings with winds at 20mph and gusts. At times the hexa was tilted over 10 degrees to fight the wind. It was fun in a weird sort of way to try and get it to hover in such a small area. I will say that the Graupners were more efficient that the DJI props. I got an extra 2 mins before the second level of the battery monitor kicked in. That would give me about 20% more flying time or about 10mins. I am happy with that. I will reserve full endorsement until I can at least test them within the parameters specified by DJI, i.e., 17mph.
P.S. The 1/3 hp drill press with keyless chuck was $80 at Harbor Freight and the step drill was $13.
Attachments
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Graupner USA.
http://www.v-eastonline.com/categories/Graupner-Prop-Shop/Graupner-E-Props/
It appears that they have 8's, 9's and 10's both R and L in stock.
http://www.v-eastonline.com/categories/Graupner-Prop-Shop/Graupner-E-Props/
It appears that they have 8's, 9's and 10's both R and L in stock.
Last edited by a moderator:
just recieved my new graupner 8x5 verry smooth flying on my quad. But how do i secure these props best on the standard dji motors? I drilled them to 8mm so the fit the shaft ok. But the normal dji prop are locked beceause they get stuck on the shaft. For now I just realy titened the prop nut. How do you other people do this with the graupner props?
Micropuller
Member
Hi, multirotor newbee here.
I just bought a flamewheel 450 last week. Assembled it and started practicing using the 8" props.
On the 5th flight, I came too close to a wall and broke one prop. So I went ahead and mounted the 10" props that came with the kit.
Just seconds after taking off, one of the props flew apart in mid air, with the flamewheel crashing as a result (breaking 2 other props in the process)
So, I ordered some more props (again, Dji props, 2 sets 8", 2 sets 10") I mounted a set of 8" props and went out.
At first everything was fine, but after maybe a minute the flamewheel started drifting to one side. I landed and noticed the props made a buzzing sound when i spun them up.
On further inspection, I noticed that two props had a cracked hub.
What am I doing wrong? I try to make sure I don't overtighten the prop nuts (I put a little dab of Loctite 222 on the threads, tighten the nut using just my fingers and then use the wrench to tichten it maybe another 1/8th of a turn) I just want to fly my multi without worrying about crashing it because one of the props could explode at any second!
I just bought a flamewheel 450 last week. Assembled it and started practicing using the 8" props.
On the 5th flight, I came too close to a wall and broke one prop. So I went ahead and mounted the 10" props that came with the kit.
Just seconds after taking off, one of the props flew apart in mid air, with the flamewheel crashing as a result (breaking 2 other props in the process)
So, I ordered some more props (again, Dji props, 2 sets 8", 2 sets 10") I mounted a set of 8" props and went out.
At first everything was fine, but after maybe a minute the flamewheel started drifting to one side. I landed and noticed the props made a buzzing sound when i spun them up.
On further inspection, I noticed that two props had a cracked hub.
What am I doing wrong? I try to make sure I don't overtighten the prop nuts (I put a little dab of Loctite 222 on the threads, tighten the nut using just my fingers and then use the wrench to tichten it maybe another 1/8th of a turn) I just want to fly my multi without worrying about crashing it because one of the props could explode at any second!