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Old Apr 22, 2012, 02:02 PM
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Why a hole in the middle?

How come most designers of multi rotor like to put a hole in the middle of the center plate? It weakens the structure substantially. If holes are necessary to route the wires through put them on the side between the arms.
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Old Apr 22, 2012, 02:13 PM
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weight....
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Old Apr 22, 2012, 02:36 PM
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I've never had structural issues with the hole.
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Old Apr 22, 2012, 04:12 PM
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I would guess it is for ease of access for wiring and configuring flight controllers

I agree it is not needed and can make the flight controller more vulnerable in a bad crash.
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Old Apr 22, 2012, 05:02 PM
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Originally Posted by Morphin View Post
weight....
1) Try to weigh the material of the hole in the center and see how much you save.
2) You can put a whole lot more holes on the circumference instead of one hole in the middle and you will save more weight.
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Old Apr 22, 2012, 05:02 PM
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Originally Posted by TheX View Post
I've never had structural issues with the hole.
That doesn't mean anything. It only means that you have not built or flown enough multi rotor to notice it.
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Old Apr 22, 2012, 05:03 PM
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Originally Posted by Adidas4275 View Post
I would guess it is for ease of access for wiring and configuring flight controllers

I agree it is not needed and can make the flight controller more vulnerable in a bad crash.
Again you can have multiple holes on the circumference of the center plate versus one hole in the middle to route the wires.
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Old Apr 22, 2012, 05:04 PM
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Completely agreed. I was just trying to conjecture why so many frames today have one in the middle.

Looks like I failed
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Old Apr 22, 2012, 05:12 PM
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Ideally, right in the center of the copter is where the Accelerometer should be mounted. I have no idea other then what has been previous stated.
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Old Apr 22, 2012, 05:20 PM
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I agree with OP. With a CF plate you don't need to cut so many large holes.
a) It weakens the structure
b) some holes are so large that you can't place the electronics there.

Seems like many just duplicate others without giving it any original thoughts and design.

Here you can see the designer only drills small holes and yet the full surface is usable.



This is another great design where the center plates are fully solid:

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Old Apr 22, 2012, 05:43 PM
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Originally Posted by Adidas4275 View Post
Completely agreed. I was just trying to conjecture why so many frames today have one in the middle.

Looks like I failed
I cannot figure that out either. Having one hole in the middle is the worst for structural integrity. Ask any structural engineer. Instead holes around the center plate will be a lot more useful.

Just to be fair I have seen some designs with no holes in the middle.
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Old Apr 22, 2012, 05:47 PM
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>>a) It weakens the structure
b) some holes are so large that you can't place the electronics there.<<

Definitely.

>>Seems like many just duplicate others without giving it any original thoughts and design. <<

That is the answer I have been looking for. I think a lot of the multi rotor designs did not come from some one's original idea or research. They are just all copying each other.

>>Here you can see the designer only drills small holes and yet the full surface is usable.<<

Holes look cool. IMHO instead of holes the designer can also use thinner materials.

>>This is another great design where the center plates are fully solid:

[IMG]http://shop.carboncore.co.uk/WebRoot/Store2/Shops/es140672/MediaGallery/CarbonCore_Octo_Mega_Spares.<<

I know Sergei has a lot of problem when he was selling his products under RC carbon. His quality control was non-existent. It seemed like he was producing while he was drunk. I have carbon fiber arms from him that has more air pockets than a sponge. OTOH he is a pretty good designer.
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Old Apr 22, 2012, 05:50 PM
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All those little bits they cut out go towards making homes for orphaned mice and little people
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Old Apr 22, 2012, 05:50 PM
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good to know

Quote:
Originally Posted by SeismicCWave View Post
How come most designers of multi rotor like to put a hole in the middle of the center plate? It weakens the structure substantially. If holes are necessary to route the wires through put them on the side between the arms.
Figure first designs were so...and as most people don´t like to copy......evolutioned (o better "creationism" in this thing...) this way till 100000 center plates broken show the good way...

Saludos and have fun,
Jose
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Old Apr 22, 2012, 05:53 PM
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Quote:
Originally Posted by SeismicCWave View Post
I know Sergei has a lot of problem when he was selling his products under RC carbon. His quality control was non-existent. It seemed like he was producing while he was drunk. I have carbon fiber arms from him that has more air pockets than a sponge. OTOH he is a pretty good designer.
Serious? I was really looking forward to consider them. Are you saying the CarbonCore has serious quality control with their products?
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