When you see how hard a stop can be .... from fwd flight even at moderate speed ... let go the sticks and that's one **** of a stop !!
Nigel
Nigel
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Safe speed to avoid motor cracks?
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And when you see plenty stock, Phantoms that never crack despite any amount of hard braking, high speed, never balancing props or doing anything else that's been put forward as a preventative measure, what does that say?
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I think Dazmatic nailed the problem - vibration. A lot of inexperienced drone pilots continue to use props that have banged into a tree, wall, etc, and because they "look OK", they continue to use those props. If you hit something w/your props, they are no longer balanced - period. Once you start revving that prop at 20Krpm, motor mount vibration and stress occur...thus the cracks. Props are relatively inexpensive. If you hit any stationary object, once landed, remove the prop(s), trash them and put new ones on. (I know there are prop balancing devices for you purists out there, and I applaud you...but much less stressful for me to just put a new one on.;-))
Sorry but this thread has taken on style and bias that has lost sight of the original intent.
Bye ....
Nigel
Bye ....
Nigel
I have a lot of time for you, Nigel, but this analogy, frankly, is ridiculous.
The issue with the Ford Pinto was a cost-saving, in-built design flaw, the danger of which was known by Ford and which affected every single Pinto sold. DJI 3 series shell cracking is NOT an inherent design problem, but which is, I believe, a result of poor injection moulding manufacturing and/or over torquing of the motor mounting and end shell bolts. I say this as the problem - and I'm not saying there isn't a problem - does not affect every single 3 series AC that has been sold globally. If it had, there would be 00's of 000's of complaints on this and all the other RC forums, and which would probably make national news too.
No worries - I agree that the Pinto problem was all Pintos built up to the recall ... so a bit unfair. But its to make a point.
I know quite a few owners of Pinto's at that time who said - mine's fine, why should I lose it while Ford play games with it .. They cited that very few incidents that brought out in the open the design error and you needed a specific RTA to bring that error into play.
I've been argued against by an unsubstantiated perceived evidence that its not a problem. It gives definite impression and indication to newcomers to ignore the possibility of cracks. Which in my view is wrong. I have never claimed that ALL Phantoms will crack. My claim is that its possible.
I have two shells both of later form, one a Standard and other a Pro. There are a mix of Std, Adv and Pro in our club. Bought different times / different sellers ... and all show signs of cracks.
Nigel
Totally in agreement with solentlife on this, have owned a p 1, 2 & 2 x 3 advanced, the first advance was bought brand new from maplins & within 10 flights sure enough one of the arms under the motor had developed cracks, my current has done 8 flights with zero issues thus far, my phantom 1 & 2 both had a few crashes inc 1 full speed into a tree in atti mode & neither cracked or showed signs of stress, only issue I had was a bent gimble! Just hoping & praying the new one lasts as the previous one was always flown steady & hand caught but put me off flying again till now!
Largely agree with this BUT only a few new props (from 3 or 4 new sets) were found to be balanced when I did mine - so I would not assume that new DJI props are balanced.
OK ... someone explain why there are so many posts all over internet similar to this one :
Darn CRACKS alright!
We can leave out the extreme wording ... the fact is another post reporting the cracks. How many do I or anyone else have to read ?
I crashed my P3P today ... the hairline signs I had inside I noted earlier - have not increased since I fitted the plates. Of course plates were removed for packing and sending back to DJI for repair of busted Gimbal etc. I have admitted to DJI Pilot Error for the damage anyway. I just don't want a lecture from DJI about non DJI gear ... because that's what it comes down to.
Nigel
Darn CRACKS alright!
We can leave out the extreme wording ... the fact is another post reporting the cracks. How many do I or anyone else have to read ?
I crashed my P3P today ... the hairline signs I had inside I noted earlier - have not increased since I fitted the plates. Of course plates were removed for packing and sending back to DJI for repair of busted Gimbal etc. I have admitted to DJI Pilot Error for the damage anyway. I just don't want a lecture from DJI about non DJI gear ... because that's what it comes down to.
Nigel
Hmmmm. Well, that's really not good I agree, but I really do think it is coincidental, but darned annoying and expensive in terms of replacement time if its out of warranty.
Perhaps a better comparison would be the dash air vent cover on the MKIII Fiat Punto.
From the day of release to the date of a complete dash redesign 3 or 4 years ago I think, "many" of these large plastic injection mouldings cracked and sprang open at the NS and OS and the cover and plastic brackets had to be replaced. Now, when this first showed up, you'd think by the number of complaints that every single Punto was affected, but that was just is not the case. Yes, it could indeed fail, as was the case with our sons 2007 brand new Punto, which failed by the time it'd reached 500 miles, but the replacement parts that were fitted have been fine - now it's 10y/o and has 90k, but some poor customers had them replaced again and again and again. However, there was not an inherent design issue - it was simply down to the person who installed the part in the factory - if it was not exactly in the correct location, it was guaranteed to fail - 100%; if it was fitted correctly, it did not.
In relation to my 3A, I have no doubt whatsoever that it would have failed, given the ridiculously high torque many of the motor and end shell bolts had been tightened to in the factory.
I had a Ford Capri 2.8i Special ... one of the early Specials fitted with the LSD.
One day I was 'flying' down the Shoreham bypass in UK at xxx mph ... and slowed to take the roundabout....
Back wheel snapped off at the brake back plate, folded under the car luckily ... car slid and came to a stop without hurting anyone.
RAC rescue came and hitched up the car to truck it back to Dealer ... it was 2 days before end of warranty.
RAC guy while we were on road back to home town with the car started telling about the number of similars he'd seen and knew about via the Auto Rescue network ... info was that a run of Granada's, Capris with the same drive shafts suffered sheering. Mine was one ....
Because of the time till warranty expiry - we agreed to put the car across the workshop doors late that night - which meant they would have to move the car to start work next day. We had the night security log the date, time and location of the vehicle ..............
Guess what -
Dealer accepted the fault and started work on the car. But Ford representative then halted the work, advised that car was to go to Ford for estimated 3 months evaluation / testing and then they would decide outcome.
I refused and had the backing of the dealer but Ford stood adamant. I called in Assessor to independently inspect. I had statements from the mechanics that the Assessor I paid for failed to inspect fully and 'listened' to Ford guy on site.
That shaft fault was never accepted on any Ford vehicle in UK ... pushed aside by delays and ignoring any action by owners. I ended up having my Insurance Co. repair the car .. which I sold immediately it was completed.
So ask me if I have faith in any large company ?
Sorry to hijack the thread ...
Nigel
One day I was 'flying' down the Shoreham bypass in UK at xxx mph ... and slowed to take the roundabout....
Back wheel snapped off at the brake back plate, folded under the car luckily ... car slid and came to a stop without hurting anyone.
RAC rescue came and hitched up the car to truck it back to Dealer ... it was 2 days before end of warranty.
RAC guy while we were on road back to home town with the car started telling about the number of similars he'd seen and knew about via the Auto Rescue network ... info was that a run of Granada's, Capris with the same drive shafts suffered sheering. Mine was one ....
Because of the time till warranty expiry - we agreed to put the car across the workshop doors late that night - which meant they would have to move the car to start work next day. We had the night security log the date, time and location of the vehicle ..............
Guess what -
Dealer accepted the fault and started work on the car. But Ford representative then halted the work, advised that car was to go to Ford for estimated 3 months evaluation / testing and then they would decide outcome.
I refused and had the backing of the dealer but Ford stood adamant. I called in Assessor to independently inspect. I had statements from the mechanics that the Assessor I paid for failed to inspect fully and 'listened' to Ford guy on site.
That shaft fault was never accepted on any Ford vehicle in UK ... pushed aside by delays and ignoring any action by owners. I ended up having my Insurance Co. repair the car .. which I sold immediately it was completed.
So ask me if I have faith in any large company ?
Sorry to hijack the thread ...
Nigel
Maplins exchanged the drone after a very big struggle but didn't comment any further, firstly they refused & said it was down to user error & I explained it has never been crashed, I therefore threatened to go to our local radio station of which they soon changed there stance luckily for myself, some other unfortunate people might not be so lucky, I'm based in UK & my local CEX branch sell used drones, in the Milton Keynes store they have a p3p in the window, I asked to view it, sure enough under 2 of the arms directly below the motors were the same identical stress cracks as my previous p3a! Surely that must tell you it's a much more wide spread issue than you think?!
This is the problem .... convincing people that its possible.
Of course there will be P3's without cracks.... but we are playing with a plastic item. Please can someone actually name ONE plastic item that does not eventually crack or break ? It does not matter what item in our life - plastics have invaded and provided manufacturers with the ideal material.
It can be poured, blown, vacuum moulded, made into any shape much easier than any other material. It gives designers opportunity to explore design concepts.
But it has one basic flaw : Life expectancy before breakage. Meaning that manufacturer knows you will go back for replacement if it lasts enough time to justify price.
Nigel
None thus far, I'm only 8 flights in but still my confidence is low hence why it sat there a while unused, I told myself from the word go to fit the reinforcement plates this time round but why should I have to adapt a brand new out the box phantom just to gain a small amount of assurance that isn't 100% gaurenteed, I haven't heard of the problem happening in p4's only p3's, if my finances at the time would have allowed a p4 I would have got my money back & purchased one but why should dji get away with selling a known product that has had numerous accounts of the same fault? Shell aside my p3a has been faultless to be fair
I understand peoples questions ... Do you have cracks ...
But am I only one that thinks that possibility of even just a few of the design to crack even without stressed flight is unacceptable ?
We are not talking a $5 item ... or even a $50 model ... this is an item that constitutes fair whack of money invested in. Many people save up to buy such a model and expect long-term use and quality.
Maybe I'm old fashioned in having this view ?
Nigel
But am I only one that thinks that possibility of even just a few of the design to crack even without stressed flight is unacceptable ?
We are not talking a $5 item ... or even a $50 model ... this is an item that constitutes fair whack of money invested in. Many people save up to buy such a model and expect long-term use and quality.
Maybe I'm old fashioned in having this view ?
Nigel
Completely agree solentlife, dont get me wrong it's a really impressive piece of kit once in the air filming but 100% there is definitely an issue either regarding the design or quality of "some" shells that DJI should accept fill responsibly for imo
If you search the P2 forums for cracking relative to all posts, and search the P3 forums for cracking relative to all posts, I am certain you will find a much larger percentage of complaints in the P3 forums. So if that's true, what changed between the P2 and P3?
It seems to me the cracking problem more likely has something to do with thrust rather than plastic composition or motor screw torque. While the P3 motors are a little stronger than the P2 motors, the biggest difference seems to me to be the hard "air-braking" introduced with the P3. I suspect softening that braking via a firmware upgrade may do a lot to resolve the problem. We can also try to manually brake softer, but that's pretty hard to do. It would take a lot of practice. The software wants to take over and brake hard anyway.
MHO
(otoh, the other argument is if it was that easy to fix, dji probably would have done it already)
It seems to me the cracking problem more likely has something to do with thrust rather than plastic composition or motor screw torque. While the P3 motors are a little stronger than the P2 motors, the biggest difference seems to me to be the hard "air-braking" introduced with the P3. I suspect softening that braking via a firmware upgrade may do a lot to resolve the problem. We can also try to manually brake softer, but that's pretty hard to do. It would take a lot of practice. The software wants to take over and brake hard anyway.
MHO
(otoh, the other argument is if it was that easy to fix, dji probably would have done it already)
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