When you spool down the motors how much do the folding props fold or get off their outstretched position? A photo of the drone from above after the motors stop would be much appreciated
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Question for all with folding props.
- Thread starter mmarian
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It depends on how much tension you have adjusted on them with the holding bolts. They move a lot if not tightened. Don't worry about it because ceentrifical force will keep them in the best flight position.
What is a lot? The Inspire 2 applies breaking force to the motors upon spooling down, so how much they fold upon spooling down would be a good visual reference for me to determine if my screws need to be tightened or loosen up a tiny bit. That's why I asked for you guys with Koptermax or T-motor props to share photos of your props position after spooling down. Do they remain fully outstreched or do they fold a "bit". How much is that "bit" is what I'd like to see.
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Covered previously ( use the search function) but for ease I will repeat my advice in one of the other threads.....
"Folding props (on any airframe) should not be too stiff so that the rotation of the props does not extend them fully, however they should not be too loose either since deceleration in that instance would cause issues.
A good rule of thumb is to torque the retaining fastenings so that when the aircraft is tipped on its side the prop just about stays where it is folded (but only just).
I hope that is of some help."
That would suggest that the props should be fairly loose. The spooling down of the Inspire 2 is done by applying breaking to the motors by the ESC. That breaking force induces force on the props making them to fold. How much do they fold is what I would like to see to be able to compare to my props. Since the breaking force and therefore the deceleration of the motors should be pretty much same on all Inspire 2 drones, seeing the props after spool down would be a good indicator of the right stiffness. Do the fold completely or just move a fraction from their fully outstrached position? I'd like to see a few photos from a few users of Koptermax and T-motor props.
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There is nothing new here, reverse emf braking has been around since the introduction of the Inspire 1.
It is of little consequence since the rotational direction is maintained even under severe braking (which is only exhibited if someone goes from full stick throw to letting go and allowing the stick to self self center). In reality, nobody is going to fly like that for cinematic/photographic purposes.
The mass of the props do not have sufficient inertia to cause any problems under braking so long as they are not so loose they flop about (as mentioned above)
You are worrying over a non issue.
3
I am not worrying about a non issue. The tension of the screws needs to be just right for the folding props working optimally. Too tight and the props will not outstretch fully, too loose and the props will flop and partially fold upon each deceleration and acceleration of the motors in flight. All I am trying to establish is the optimal tension of the screws on my Koptermax folding props. The described process of spooling up and down and seeing the position of the props when the motors stop would be a good indication of comparing tension on my props with tension of others. That is all I am trying to find out. One photo or short video is all I am after to help me see if my props have the right tension on the screws.
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The ONLY way to have the correct tension is by having torque settings in Newton Meters (or Ft/lbs) from the manufacturer.
Since that is not available it is by trial and error and experience.
I have been flying multi rotors and RC helicopters with folding blades for 30 years.
Seeing where the props are when the motors have stopped is pointless. The blade grips will wear over time in any case and you would be forever tightening the bolts to get back to your 'setting'
See my post above - a small amount of friction is sufficient, or torqued to the manufacturer specifications.
Believe me - you are concerned about a total non issue.
But it's your time..............
I'm out.
The comparison with helicopters is pointless. I have been flying helis for 10 years and have been "the preferred mechanic" for all my heli club colegues because I have the natural feel for these things.
You can not compare helicopters to I2 because they do not have induction breaking, so the blades just keep spinning till they stop.
I2 is different because Inspire 2 motors stop rapidly on spool down due to build in induction braking hence the innertia of the spinning props forcing them to fold against the braking force applied on the hub from the motor. Therefore upon stopping the motors the props are no longer in fully outstretched position but partially folded. I just want to see a picture of somone elses Koptermax props how much do they fold upon motors stopping. That's all. If you can't see my rationale that's fine. But if you could do me the favour and post that picture of the props upon spooling down, I would sincerely appreciate it and it would help me a great deal. Thanks. Trust me I know what I am doing and why I am asking for this.
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Perhaps just try to get a recommendation from DJI or stick with the standard issued props/replacements.
Done deal.
Done deal.
With all due respect to all who cared to reply and elaborated extensively, can actually someone post a photo of what I asked? That would be great?
Florida Drone Supply
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Hello @mmarian - we sell both brands of folding props that you mentioned above and would be happy to take a couple photos of the positions of the blades after they spool down. Based on our experience with folding props, different manufactures design them to operate differently. The T-Motor props generally arrive a little over tightened and take too much force to open up and do not move much at all when the motors stop. We generally back the tension screws off 1/8 or 1/4 turn to make them a little looser - but not sloppy loose (much like @The Editor described above). The Koptermax seem to be looser, the M600 are somewhere in-between, the smaller DJI aircraft are very loose, and we used to have Freefly Altas which also had very loose spinning folding props.
All that being said, I am traveling back from the AUVSI show in Chicago but would be happy to get you some photos or a quick video of the being powered down.
All that being said, I am traveling back from the AUVSI show in Chicago but would be happy to get you some photos or a quick video of the being powered down.
Haleluya
Hallelujah!!!! Thank you kindly for your to-the-point reply and I look forward to see the photos. If you'd prefer you can send me the photos via PM to avoid further pointless discussion in here which BTW was not what I was seeking. Just Koptermax please, that would suffice.
M.
The information that Florida Drone Supply just gave you is the exact same information they gave me when I purchased the Tmotor winglet CF folding propellers. IMHO opinion it’s a matter of using them for awhile and then you’ll get the hang of it.
There’s no exact science to it, just experience!
There’s no exact science to it, just experience!
Without going deeper into explanation behind my original request, which the readers would likely find quite funny, I will only say that I am not the one who started to complicate this. All I asked for was a photo of the props after spool down to see their position relative to the hub. The rest was just needless discusion which I got regretably sucked into?
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May I suggest to wait for the photos from Florida Drone Supply before jumping to conclusion.
I apologize for my last comment and quite possibly the photos that FDS supplies will answer all your questions. Other than that I hope you find the answers to your questions asap.
My I1 Koptermax props remain outstretched pretty much straight after shutdown. I never spool up the motors with them folded, I did it once and did not like how they looked, seriously out of balance, probably not good for the motors.
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