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Correct motor mount angle

- @Jeff. Can you please tell in which condition you make your mesurement : 1 You take the drone in landing mode and you put it on a table or 2. you put it on a table in transport mode and active the landing mode and let the aircraft come alone in landing mode.

I place the I2 on a table in transport mode, I then convert it to landing mode and take the measurement. It’s pretty consistent every time.

As to your question about glue and screw tightening, I would never use glue unless it was designed to be there. As to screws, I use blue loktite on the threads and only tighten down until any unnecessary motion of the restrained component is removed.
 
to Clarify my loctite comment. Only use loctite on places that have metal receivers. Never ever Loctite to plastic it will eat it alive.
 
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thanks jeff, also did you have the height of propeller at the center of the frame ? (around 21,cm) ?

Thanks
 
I discovered my front props to be off a fair amount, so after aligning the front props to be the same, I checked the rear props..they were off even further than the front before I adjusted anything..seems Frank and company “Split the difference” on mine.
 
thanks jeff, also did you have the height of propeller at the center of the frame ? (around 21,cm) ?

Thanks
Sorry for the delay
Here ya go
 

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Well I adjusted mine. Once side was one notch too high and the other, one notch to low. They are now 21.5 cm on both sides like above in landing mode but when I transform it for flight mode one side is slightly higher than the other by a couple of mm, so something is still a bit out. Will test fly later this week and report back.
 
In my tinkering with the relevant angles of the motors, I've found that a 93-97 degree variance is tolerable. Just as long as the arms do not have a difference of more than a couple degrees between them. Anything further than that, you're bound to have some issues.
 
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Greetings!
Late to this party but still bearing gifts, I rebuilt my third Inspire 1 recently and can report setting a common anhedral angle of 3 degrees in all three builds.

I arrived at the number by
a) taking photos of my Inspires while in flight and when new.

As a long-time pilot, I noticed the anhedral set of the props immediately and thought there might well have been something wrongly set up with my bird.
However, more shots of other Inspire 1's confirmed that the unusual prop and motor angle was, in fact, designed that way.

b) the giveaway for me has been the set of the Inspire's feet when in landing/takeoff mode.

If I set up the drone on glass or other flat surface, the bottoms of the landing gear feet (its "soles", I.e.) have a slight but very definite angle to them. If I relax the prop angle screws and let the craft settle down on its feet properly, I can see that my prop angles also settle down to around 2-3 degrees anhedral. There's nothing tentative about it - it settles down with a solid "clunk". And stays there. Subsequent measurement with an RC heli prop angle tool yielded the 2-3 degree angle result.

BTW I use the same glass technique when building the booms/motor mounts to ensure that fore and aft motors are aligned and their drive shafts are in line.

Slightly political rant and thoughts follow:

DJI mystique and monopoly aside, these are, bottom line, R/C aircraft, and must follow all the rules of same, even if made in China by an company with delusions like Apple.

It would be very interesting to get the FAA to go after them to issue us with a manufacturer's POH with all the manufacturer's flight data clearly stated, since the FAA rules that we are rPICs and bear the responsibility of pre-flight inspection at the very least.
In fact I think the FAA's definition of a UAV and their licensing laws kinda mandate that, don't they?

Oh - sorry - pilot speak is a bore!
FYI if you need it:
FAA: the USA's Federal Aviation Authority
POH: pilot's operating handbook. Every real aircraft has one.
rPIC: remote pilot in command
UAV: unmanned aerial vehicle

Happy Holidays!
Chris
 
Greetings!
Late to this party but still bearing gifts, I rebuilt my third Inspire 1 recently and can report setting a common anhedral angle of 3 degrees in all three builds.

I arrived at the number by
a) taking photos of my Inspires while in flight and when new.

As a long-time pilot, I noticed the anhedral set of the props immediately and thought there might well have been something wrongly set up with my bird.
However, more shots of other Inspire 1's confirmed that the unusual prop and motor angle was, in fact, designed that way.

b) the giveaway for me has been the set of the Inspire's feet when in landing/takeoff mode.

If I set up the drone on glass or other flat surface, the bottoms of the landing gear feet (its "soles", I.e.) have a slight but very definite angle to them. If I relax the prop angle screws and let the craft settle down on its feet properly, I can see that my prop angles also settle down to around 2-3 degrees anhedral. There's nothing tentative about it - it settles down with a solid "clunk". And stays there. Subsequent measurement with an RC heli prop angle tool yielded the 2-3 degree angle result.

BTW I use the same glass technique when building the booms/motor mounts to ensure that fore and aft motors are aligned and their drive shafts are in line.

Slightly political rant and thoughts follow:

DJI mystique and monopoly aside, these are, bottom line, R/C aircraft, and must follow all the rules of same, even if made in China by an company with delusions like Apple.

It would be very interesting to get the FAA to go after them to issue us with a manufacturer's POH with all the manufacturer's flight data clearly stated, since the FAA rules that we are rPICs and bear the responsibility of pre-flight inspection at the very least.
In fact I think the FAA's definition of a UAV and their licensing laws kinda mandate that, don't they?

Oh - sorry - pilot speak is a bore!
FYI if you need it:
FAA: the USA's Federal Aviation Authority
POH: pilot's operating handbook. Every real aircraft has one.
rPIC: remote pilot in command
UAV: unmanned aerial vehicle

Happy Holidays!
Chris
This thread is regarding the Inspire 2 and the correct angle on both aircraft is achieved using a jig which is not available to the general public
 
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Sorry, Mr. Editor -
Really??
Is the Inspire 1 not an aircraft, under FAA regulations?
Doesn't it have an anhedral/dihedral angle like almost all winged aircraft?
Does the PIC not have command of his craft, not necessarily as a mechanic, but to do an accurate pre-flight?
Does the FAA not mandate that for its 107 pilots?

So - doesn't this apply to Inspire 2's as well?
Maybe the actual angle number itself might be different, but every other "real" vehicle on the planet has manufacturer's specs that are published.
"Not available to the public" is, IMHO, simply Apple-style nonsense.
If the FAA mandates PIC responsibilities in UAVs, especially upscale UAVs like the Inspires (not just the more expensive ones - let's forget about snobbery, shall we, just for a moment? And think about safety in flight, Rule #1 in any flight manual or rule book?
Which way do they want it? Is it a toy to be returned to the manufacturer every time it malfunctions by its owners/drivers?
Or is it a remote aircraft piloted by rPICs?
 
Sorry, Mr. Editor -
Really??
Is the Inspire 1 not an aircraft, under FAA regulations?
Doesn't it have an anhedral/dihedral angle like almost all winged aircraft?
Does the PIC not have command of his craft, not necessarily as a mechanic, but to do an accurate pre-flight?
Does the FAA not mandate that for its 107 pilots?

So - doesn't this apply to Inspire 2's as well?
Maybe the actual angle number itself might be different, but every other "real" vehicle on the planet has manufacturer's specs that are published.
"Not available to the public" is, IMHO, simply Apple-style nonsense.
If the FAA mandates PIC responsibilities in UAVs, especially upscale UAVs like the Inspires (not just the more expensive ones - let's forget about snobbery, shall we, just for a moment? And think about safety in flight, Rule #1 in any flight manual or rule book?
Which way do they want it? Is it a toy to be returned to the manufacturer every time it malfunctions by its owners/drivers?
Or is it a remote aircraft piloted by rPICs?
Yup really.

Certain maintenance/set ups are not designed to be tinkered with by the end user (although many do) and have zero to do with air worthiness.
I fly a fleet of UAS by different manufacturers and am CAA authorised in various weight class of aircraft to operate commercially as well as certified for night flying.
My ops manual is submitted annually and in order to gain my qualifications I also underwent a practical flying examination (which I understand the US does not have/bother with). This included pre/post flight checks (under observation), mission planning, site survey, crew briefing and post flight de-brief.
At no point in my years of flying multirotors commercially have I been asked or required to know what angle the props should be set at.
So, to answer your question - yes really.
 
Either here or in the DJI forum there is a post that shows a precise measurement chart, from the outside tip of the propeller to the surface (of course a flat balanced surface) This measurement includes aftermarket props of carious lengths. I just don't remember the post name or exactly which forum it's on, I don't find it here but will try a couple other key words. However, I think you are talking I2? chart is for I1
 
Either here or in the DJI forum there is a post that shows a precise measurement chart, from the outside tip of the propeller to the surface (of course a flat balanced surface) This measurement includes aftermarket props of carious lengths. I just don't remember the post name or exactly which forum it's on, I don't find it here but will try a couple other key words. However, I think you are talking I2? chart is for I1
After all, the specific exact angle of propellers is not that critical. Propeller's tips must not collide with front OA sensors, providing reasonable and equal clearance on both sides. That's it.
 
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After all, the exact angle of propellers is not that critical. Propeller's tips must not collide with front OA sensors, providing reasonable and equal clearance on both sides. That's it.
I would personally not encourage people to be complacent about not having the angles of motors equal. IMHO they should be as close to perfectly equal as possible and adjusted if that is not the case. If the angles of motors are not equal on both sides that will cause all sorts of undesirable flight characteristics and aerodynamical issues. For starters the IMU will have to compensate for unequal lift vector on both sides of the craft and the craft will hover tilted to one side and thus the dynamic CG will be away from the CG of the craft. Yawing the craft while hovering will be unstable and will have tendency of exhibiting toilet bowl effect. (Otherwise also caused by discord between GPS true north and magnetic north). That is just one issue resulting from the different motor angles.
Anyway, without going too deep into other issues resulting from the unequal arm/motor angles I would encourage people to either adjust the angle themselves if the difference is close to or more than 1/2" between the prop tips facing each other. Or if not comfortable with tinkering, send it in for repair.
 
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Thanks guys this is rely interesting...

Can you give me two precisions please :


- @Jeff. Can you please tell in which condition you make your mesurement : 1 You take the drone in landing mode and you put it on a table or 2. you put it on a table in transport mode and active the landing mode and let the aircraft come alone in landing mode.

I ask this cause i notice there is difference from 5mm in the 2 different way, i suppose its due to when you let the aircraft come in landing mode there is some resistance on the surface (2).

- when you tight the screw adfter arm adjustement, did you put glue and how much did you tight it ? just a little hand resistant or you tight strong ?

Thanks
did you ever get any more answers ?
 
did you ever get any more answers ?
Firstly, I can not emphasise strongly enough to addopt routine to lift the drone off the ground by hand before the transition starts and keep it in the air until the transition is fully completed. Always !!!
The measurement of distance between the ground and the tips of the two front props facing each other should be equal or as close as possible to equal. I tighten the screws so that the collar around the CF tube has a bit of gap left and I personally apply a bit of blue Loctite on the thread of the srew before tightening. I check periodically if the arms are solid and held in position by trying to twist them gently holding the motors. The amount of force applied must not me excessive, just gentle.
 
I would personally not encourage people to be complacent about not having the angles of motors equal. IMHO they should be as close to perfectly equal as possible and adjusted if that is not the case. If the angles of motors are not equal on both sides that will cause all sorts of undesirable flight characteristics and aerodynamical issues. For starters the IMU will have to compensate for unequal lift vector on both sides of the craft and the craft will hover tilted to one side and thus the dynamic CG will be away from the CG of the craft. Yawing the craft while hovering will be unstable and will have tendency of exhibiting toilet bowl effect. (Otherwise also caused by discord between GPS true north and magnetic north). That is just one issue resulting from the different motor angles.
Anyway, without going too deep into other issues resulting from the unequal arm/motor angles I would encourage people to either adjust the angle themselves if the difference is close to or more than 1/2" between the prop tips facing each other. Or if not comfortable with tinkering, send it in for repair.
I just cant seem to get motor angle correct when im trying to tighten everything back.
 
I just cant seem to get motor angle correct when im trying to tighten everything back.
Because the angle of the arms changes marginally as you are tightening the screws and the collar tightens around the the CF tube. You need to work out how much the arm should be off before tightening the screw and then tighten it. It is trial and error kind of job but it can be done to almost perfectly equal angle on both arms.
 

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