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Old Oct 02, 2013, 06:54 PM
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1s micro/mini brushed quadcopter specifications and performance data

Discussion will continue in this thread however it is finally at a point where most testing planned is completed and readers will hopefully be able to reference this first group of posts and find the information they are looking for.

Many of us using brushed micro and mini sized quadcopters are flying different quads with different components and much of the technical data collected regarding their characteristics and performance ends up spread across many threads. This can make it difficult to locate various technical details for a given quad or component. The aim of this thread will be an attempt to provide one place to collect and record technical/performance data regarding the characteristics of these quads and their components, particularly the components of the more popular and readily available ones.

If I run across something relevant to this thread I will gladly copy it over (or link to it), but am only one person so the strength of this thread will ultimately rest on interest and input from the community. I will do my best to update these first few posts as appropriate.

The thread will be broken into up into sections (posts) covering the following:
Bench test setups, 6mm motors & applicable props, 7mm motors & applicable props, 8.5mm motors & applicable props, Flight Controllers, Batteries, Quad/component weights and sizes, Performance testing, Other testing/observations, pics and stats of your customized or modified quad(s) and will have an extra post available in case there is another applicable section suggested.

If anyone has comments/issues with the breakdown or amount of content please feel free to chime in and I will do my best to please the majority of those interested. If anything I post appears inaccurate or unreasonable please call it out and I'll gladly take a second look and edit where appropriate.
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Old Oct 02, 2013, 06:55 PM
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Test Setups

Test Setups
Below is a video of the basic test setup I currently use to evaluate motor thrust while measuring the current draw and voltage supplied to the motor under test. It uses a Blade Nano QX flight control board (connected to a set of fully charged lipo batteries) to drive each motor across the variable output from 1 motor channel on this board. To test a motor the current test plan is to slowly increase the output from the board (using a bound tx) from minimum to maximum over a period of approximately 10-15 seconds. The display from the scale and 2 meters is recorded using a camera and then the video is played back to collect and record instantaneous data points recorded by the camera. The thrust results obtained are then graphed against the current draw and power consumption (V*A) to generate a thrust graph for each motor prop combination tested. It’s not the most scientific method, but think it yields pretty reasonably accurate results.

Additional discussion has come up concerning the use of batteries and a specific flight controller to drive the test setup. To minimize the voltage drop across testing the same 600mAh and 750mAh batteries are connected in parallel to the flight controller and testing is completed within couple minutes before the batteries are recharged. This method will likely provide artificially high thrust results, however it still seems to be more representative of a single (potentially smaller) 1s battery than a DC power supply (although those numbers are also helpful). Additionally since only 1 motor is being driven in the test setup when multiple motors are being driven during flight, further reduction in voltage (thrust) should be expected. Although testing is completed quickly and multiple batteries are connected a small amount of voltage sag is still expected during testing. Due to this, configurations that yield results particularly close to one another will have multiple max thrust measurements completed and flight performance feedback will be used to determine which configuration is preferable.

For the Flight controller used, it has been mentioned, however not confirmed that the nQX flight controller uses a PWM rate of 4khz to drive each motor. Flight controllers using different PWM rates may provide slightly different results however significant changes in max thrust or efficiency are not expected. Jesolins indicated not seeing any noticeable difference in performance or flight time using PWM rates of 4khz-16khz in this post. I hope to eventually bench test the more favorable motor / prop configurations of 4 & 32khz.

The main idea here is to get an idea what motors will provide the best results in flight and then verify the findings with flight testing and reports from the community. The max thrust numbers provided here will probably not accurately match the maximum thrust of a multirotor in flight, but should give a reasonable point of reference to compare motor/propeller combinations and roughly estimate maximum thrust. Plots estimating the voltage sag of various batteries may be generated to help estimate actual maximum thrust in flight more accurately in the future. So far It doesn't seem the test results have steered anyone in the wrong direction and generally flight performance seems to agree with bench test results. Please chime in if you find otherwise.

1s brushed motor/propeller test of Walkera Infra-x and Hubsan x4 prop. (0 min 38 sec)


It should be noted that the motor and propeller is directed so that it pushes air upwards and itself downward toward the scale. According to posts I read to long ago to find now, having the motor blowing at the scale will have negative results on thrust measurements. Any propellers tested are hand balanced using a needle and sanded as needed.

Please share your own test setups and or improvements I could make to mine as well. Adding a method of measuring the propeller RPM and/or a motors temperature vs. thrust/time could also be interesting.

Thanks to Benedikt and Fyathyrio for sharing their setups here and here.

Additional testing has been completed to measure the unloaded RPM of each motor. Using a disk type piezo transducer attached to a pc sound card the motor RPM can be measured quite easily using the right audio software and FFT analysis. Although measuring unloaded motor RPMs is the main goal of this setup, the results from it were verified using a handheld laser tachometer when a prop was attached so I'm pretty confident it provides reasonably accurate results. A few additional details are noted in this post, more can be provided upon inquiry.
A plot of the unloaded motor RPM for each motor tested will be included in within the appropriate motor size section. Each motor will be tested at 2.5, 3, 3.4 & 3.7V. Hopefully having a better idea of the unloaded motor speed will provide one more reference point when purchasing motors for our application.
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Old Oct 02, 2013, 06:56 PM
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6mm motors & applicable props

6mm motors & applicable props
The Blade Nano QX and Estes Proto X/Hubsan Q4 are currently the only quads readily available using 6mm brushed motors.
6mm motors are readily available in 10, 12, 14 & 15mm lengths.
The Blade Nano QX uses 6X15mm motors driving 50.2mm long propellers and the Estes Proto X uses 6X12mm motors driving much smaller 29.7mm long propellers. The 2 quads are show together here thanks to KC_703.

Additional motors Tested:
6x12mm 30,000 RPM from ebay
6X14mm "High speed" motor from ebay
6X15mm HKRC Nano QX Motor from ebay
6x10mm, 6X12mm & 6X14mm High-speed Coreless Aircraft motors from ebay
Chaoli CL-0614 Spec Sheet
Chaoli CL-0615-14

Unloaded RPM testing has been completed on various 6mm motors tested and the results are provided below:
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It looks like those Proto X motors are using a very high RPM motor to get enough thrust out of those tiny props.
The 6X12mm High-speed Coreless Aircraft motors from ebay are not included because they did not run smoothly enough to complete unloaded RPM measurements.

Direct Drive Testing:
Below thrust plots are included for the various 6mm motors tested.
6X10 & 6X12mm motors:


6X14mm motors:
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6X15mm motors:
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Fyathyrio has also tested both official nQX motors and the HKRC replacement motors from Ebay and initially confirmed the motors do not have the same physical markings or motor base color. Fyathyrio also completed weight, thrust, RPM and resistance testing on each of these motors and provided the results below in this informative post which is an update of this post.
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Old Oct 02, 2013, 06:56 PM
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7mm motors & applicable props

7mm motors & applicable props
There are many micro direct drive quads and most seem to be using 7x20mm motors. A few micro and mini gear driven quads are using motors of the same size. There are so many quads using these motors I’ll start by just listing quads I have personally tested motors and/or props from and add more as info turns up.

Direct Drive Quads:
Hubsan X4 H107 V1
Hubsan X4 H107L V2
Vitality H36
UDI u816
HCW553
MJX X100 micro quad
YD717
HobbyKing Pocket Quad (uses 7X16mm motors with a smaller 0.7-0.8mm shaft diameter)
WL Toys V252
Traxxas QR1

Gear Driven Quads:
Syma X1 & X3 Note: The Syma X3 uses a shorter/lighter 7x16mm motor.
Sky Walker (This one isn’t very popular but I like it and have done some testing with it, so why not share)

Additional motors Tested:
Random 7X16mm motor purchased too long ago to link
7X16mm 39.500 RPM motor from ebay
7X20mm 50,000 RPM motor from ebay As shown below these reach nowhere near the advertised 50,000 RPM, and provide minimal thrust (shown below).
7X16 0.8mm option 2pcs Coreless Aircraft Helicopter motor High-speed from ebay
7X16 1.0mm option 2pcs Coreless Aircraft Helicopter motor High-speed from ebay
Chaoli CL-0720-12 Many thanks to Benedikt for finding these gems and making us aware of them.

Here is a link to some of the early data I collected using a few 7x20mm motors and a few propellers. That testing was limited to a 3.3v Atx power supply and a 1s battery and the information is not presented the best. It did confirm not all 7x20mm offer the same thrust and don’t all perform the best with the same propeller.

It was incorrectly reported early that the Syma X3 uses the same motor as the X1, however Sofo has confirmed it uses a different 7mm motor with a shorter length here. Sofo also provided some comparison data of the Syma X1, X3 and V959 motors in this post. I also plan to include one of these motors in my testing.

So on with some of the latest results. Below are 2 plots showing results from the
Unloaded motor RPM testing. To make the results easier to view one plot is for 7X16mm motors and the other is for 7x20mm motors.
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Below are some graphs showing the current draw and power consumed (V*A) vs. thrust output for the motors and props I have tested so far. The maximum output for each configuration is included in each graphs legend. Images of the raw data will also be included for reference. The number of data points used to generate each plot is somewhat random (partly due to lazyness) but appear good enough to generate reasonable accurate plots. I was also not particularly careful to collect data just as the motor began to spin so the bottom of each plot is somewhat arbitrary. Keep in mind testing does not cover a statistically significant number of motors and/or props so small variations between results could easily be caused by measurement variation.

Direct Drive Testing:
I’ll start with the motor from ever popular original Hubsan X4 H107:
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Next I tested a new motor for the V2 “upgraded” Hubsan x4:
As the plot shows the new motor provides almost identical thrust data as the original. I’m not sure why they made a new part number for these motors as they appear to offer the same performance?
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To ensure the propellers I am using for test are at least somewhat representative of a larger sample, a second propeller of each type was tested with the same Hubsan X4 V2 motor:
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A UDI U816 motor was then tested with the propellers on hand:
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A Syma X1 motor was then tested with the propellers on hand:
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Since the results form the remaining propellers tested fell between the Hubsan X4 and YD717 propellers, direct drive thrust testing form this point forward will mainly focus on them.

The Chaoli CL-0720 motors were originally recommended by Benedikt and have tested to be some of the most powerful 7mm motors available to direct drive the props applicable to this size motor. Motors of 11, 12 and 14Kv were tested as indicated below:
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Below are some max thrust results from additional CL-0720-12Kv motors tested with a Hubsan X4 propeller:
Direction/Voltage/Current/Max Thrust(g)
CW /3.75/1.48/25.0
CW /3.75/1.49/25.3
CCW /3.75/1.45/25.0
CCW /3.74/1.45/24.8

The Syma X3 motor is a very fast spinning 7X16mm motor intended for a gear drive setup but can produce some impressive thrust numbers although it consumes a large amount of current.

Since the Hobby King Pocket Quad uses a 7X16mm with a smaller 0.8mm diameter shaft, only the Hobby King Pocket quad and blade nano QX are a direct fit for testing.
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For motor propeller combinations that provided relatively low max thrust values a thrust vs current or power plot was not created, however the max thrust values are included below for reference.
Motor/Propeller/Voltage/Current/Power/Max Thrust(g)
Chaoli CL0720/nQX/3.83/1.2/4.6/20.1

Below plots comparing the various 7X20mm motors tested when using the Hubsan X4 and YD717 props are included below for comparison.
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There are so many direct drive micro quads using 7mm motors I cannot justifying buying a set of motors or even one for each quad available. It’s probably fair to say most of the direct drive quads are using motors very similar to (or the same as) either the Hubsan or UDI u816 variety. If another motor is highly recommended/suggested I may try to get one for test, however at the moment it seems the consensus is the faster Syma X1 style motors are the most powerful available in any of the readily available 7x20mm motor based quads. Although not used in any readily available quadcopters, the Chaoli 0720 appears to offer even better performance than the Syma X1 motor. When used in a direct drive setup, these higher spinning motors are capable of higher power consumption, but results in a quad with relatively a lot of thrust. Flight time is almost always advertised with these micro quads and speed never is, so from a manufacturers selling perspective it makes more sense to use the somewhat slower less power consuming motors.

Direct Drive Conclusions:
Of the 7X20mm motors tested the Chaoli 0720 motor offered the greatest amount of thrust followed by the Syma X1, Hubsan(original and V2) and UDI U816 motors.
With any of the motors tested the Hubsan x4 propellers offer the most efficient use of power. When using the Hubsan X4 motors the MJX X100 and YD717 propellers offer slightly higher thrust results but also draw more current/power. When used with the UDI U816, Chaoli 0720 and even faster spinning Syma X1 motors the Hubsan propellers actually produced the most thrust while drawing the least current/power of the props tested. The remaining propellers tested all yielded results relatively similar to one another, and fell between the Hubsan x4 and larger MJX X100 and YD717 propellers.
In-flight performance testing will be needed to determine if there is a benefit to using the larger sized props (MJX X100 & YD717) with Chaoli 0720 and Syma X1 motors not shown in basic thrust measurements. The image below supplied in the Hubsan thread indicates they put some effort into the propeller design and they seem to offer great performance on the bench.
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Siriusflier has confirmed approximately 8-12% longer flight times here with the Hubsan propellers when compared to the YD717 and V252 propellers. Siriusflier also provided a valuable post here, indicating similar flight performance between the Hubsan and YD717 propellers and favoring the YD717 props when flying aggressively only for durability reasons.


Hubsan/Traxxas/V959/clones propeller shootout:
I had an opportunity to do a quick side by side test of 4 different but very similar micro prop types. I tested 4 props of the following (each linked to purchase source): Original Hubsan x4 H107, Traxxas QR1, Hubsan H107 X4 (listed as Hubsan but did not arrive in any Hubsan labeled packaging) and KV252-03 listed for the H107 and V252 (from Banggood but no longer listed). Below is a quick graph showing the results.

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It appears that the Hubsan and Traxxas propellers offer the most thrust which appears to be relatively consistent between the 2. The large set of v252 propellers (KV252-03) I purchased (no longer available) offered inconsistent thrust results and appeared to contain 2 types of prop. Most came with tiny thru holes and a few without (orange and black). Taking a closer look I determined the props without the holes are noticably unbalanced (on a needle). The non authentic set of Hubsan propellers offered the worst thrust. It also appears that some of thse propellers were mixed into the large KV252-03 set of propellers purchased causing a particularly low result for one of the thrust measurements. It's probably safe to say the current set of v252 propellers offered by banggood will not have these unbalanced props mixed in and will likely provide results closer to the Hubsan and traxxas props. It appears as if the non official Hubsan props here should at least be balanced if not avoided. Their lack of performance may be indicated right in the Banggood ad, as the official Hubsan prop is recommend right in the listing.

Gear Drive Testing:
The Syma X1 and X3 use the same gear drive setup, however the X3 motor pod assembly itself is lighter, not considering the reduced weight of the shorter X3 motor. Fortunately the lighter weight X3 motor pod can also accommodate the 7X20mm X1 and Chaoli CL-0720 motors for testing and use. Similar thrust results are expected from an X1 motor pod with the same motor/propeller combo but will be slightly heavier.

I'll start with the stock Syma X3 propeller.
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Unfortunately the Syma X1 and Chaoli CL-0720 motors produced thrust values enough below the stock configuration that only max thrust points were recorded for reference.

The Stock Syma X1 propeller was then tested
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Similar to some of the Direct Drive testing the X3 motor actually produced slightly more thrust than the X1 motor, however the additional current draw may make the added thrust and lower weight of the X3's 7X16mm motor not as great as it may seem at first glance. The slower Chaoli CL-0720 motors fell short of the X1 motors in this particular gear driven setup.

Since I have found a GWS 5443 propeller can be modified to fit onto the Syma X1/X3 Drive train and provides improved flight performance, so it was also tested on the Syma X1/X3 drive train
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Again the shorter/lighter X3 motor produced the most thrust but the cost of much higher current draw. Surprisingly the Chaoli CL-0720 produced slightly more thrust than the X1 motor while consuming less current/power. Since the results are so close a second look at the max thrust is in order but will leave this plot as is. After looking at the max thrust of a group of each motor with this particular combo additional details will be provided.

The HM1306 Sky Walker drive train was also tested, with Sky Walker, Syma X1/X3 & CL0720 motors. Unfortunately no other propellers of similar size are available that would be very easy to install onto this drive train for test
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It should be noted that the Skywalker motor tested was been used for many flights prior to this testing.
It looks like the X3 motors could be a potential power upgrade for this quad, however again at the cost of higher current draw could have significant impact on flight time, potentially requiring a larger battery, negating the benefits, It does not appear like a slower spinning motor such as the Chaoli Cl-0720 is as powerful as the stock motor which appears reasonably on par with the Syma X1 motor, considering the Skywalker motor tested was used.
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Old Oct 02, 2013, 06:57 PM
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8.5mm motors & applicable props

8.5mm motors & applicable props
8.5 motors are typically used on geared quads but a few use a direct drive setup.

Gear driven Quads:
Walkera w100s
V929/WL toys V949
WL toys V959/V222
FY-999
Blade MQX
MJX X200
UDI U818a
UDI U817a

Traxxax/LaTrax Alias
Align M424
GWS 5443 propellers are also applicable to this size quad

Direct drive Quads:
Walkera QR Infra X
Hubsan H107C and H107D
Walkera w100

Additional motors Tested:
Chaoli CL-0820-15 (15.0Kv)
Chaoli CL-0820 (8.8Kv) & CL-0820 (14.6Kv) were also tested but are currently not readily available in typical hobbyist quantities.
Generic W100s/V9X9 replacement from Banggood

Below is a plot showing the
Unloaded RPM motor testing:
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Direct Drive Testing:
Recent test results I currently have only cover using 8.5mm motors in a direct drive setup. Older/quicker testing on a v949 boom arm with a V949 motor and GWS 5443 propeller yielded a maximum thrust of 48.2g @ 1.4 A. With a V959 motor installed into the same boom arm the thrust increased to 53.4g @ 1.73 A. This is approximately 10% more thrust which appears in line with what others have reported about the faster spinning V959 motor.

Below is the current vs. thrust plot obtained testing a Walkera Infra-X motor with a Hubsan x4 and a YD717 propeller.
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Since the Walkera Infra-x motor drew over 2.5A when used with the YD717 propeller I was hesitant to subject the board used to drive the test setup to such high current draw any more and continued testing with only the Hubsan X4 propeller.

Below are the results from the various 8.5mm motors tested with the Hubsan x4 propeller.
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Traxxas QR1 and WL toys V252 propellers are expected to provide similar results.

It should be noted that the Hubsan, Chaoli and generic W100s/V959 motors were tested months after the other motors. When this testing was completed a max thrust test was also completed on the Walkera Infra-X motor with Hubsan X4 propeller yielding 32g of thrust. This guarantees nothing, but is further evidence the generic W100s/V9X9 replacement may be an even more powerful choice although it does consume more power.

The low thrust results obtained with the Chaoli motor was somewhat surprising and verified with a second motor. The company does not appear to be specializing in multirotor motors, so we can't expect every motor they produce to be ideal for our application. Benedikt has now supplied additional motors that perform even better than any of the the other motors tested. Some question about the effectiveness of the PWM rate used in my test setup has come up when using these faster, more powerful motors in a direct drive setup, so testing is currently not completed, however some relevant data is available in this post in the mean time.

Gear Drive Testing:
Although there are many gear driven quads using 8.5mm motors, my testing will mainly focus on the more popular WL toys and Traxxas Alias quads. It should be noted that although I do not have official Blade mQX parts to test the WL toys V9X9 and V2X2 gear driven quads are clones of this design using the same gear ratio, similar components and are expected to have similar performance.

I'll start with plots from the V9X9/V2X2 gear drive configuration using a V959/V222 motors and various props.
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As expected each propeller design provided a different amount of maximum thrust, however there did not appear to be a significant difference in efficiency between any of the props. The V949/V929 and GWS 5443 were slightly more efficient but also offer lass thrust.

Next some different motors were tested with the GWS 5443 and Traxxas Alias propellers on the V9X9/V2X2 gear drive.
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Note: Although data is not available at the moment the V929/V949 motors typically offer 10% less power than the V959 motors. Blade mQX motors are rumored to be of similar power of the V949, however I have not personally tested any.

To get test results from the Traxxas Alias, since I could not easily mount it to my test stand, a plot of RPM vs thrust plot was first collected first for the Traxxas alias prop. A plot was also generated for the GWS 5443 prop since it seems to be the most common aftermarket propeller used on the V9X9/V2x2 geared quads. The plots were generated using the thrust stand in conjunction with a laser tachometer monitoring the propeller RPM driven by a V9X9 gear drive configuration. The formulas from these plots are then used to determine relative thrust numbers based on RPM numbers collected. They can also be used to get an idea of how fast the motors are spinning in these quads when using these propellers.
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Then thrust thrust plots were generated for the Traxxas Alias using RPM measurements to calculate estimated thrust.
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It appears that the Chaoli CL-0820-15 should be an adequate, possibly even slightly more powerful replacement motor for the Traxxas Alias. The Walkera Infra X and V959 motors will probably work with the Traxxas alias but will not provide as much thrust as the stock motors.

Plots directly comparing the stock V959/V2X2 configuration to the stock Alias configuration, as well as the V959/V2X2 with an Alias motor and prop installed were also generated.
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It's surprising how similar the plots from the two stock quads are. I was expecting the higher gear ratio of the Traxxas Alias to provide a noticeably more efficient plot. Since this does not appear to be the case it is probably safe to assume the benefits of the higher gear ratio relate more to the quads punchy flight performance since this quad is rumored to be a more agile flyer than the V9X9/V2X2 variant even with a higher flying weight.

Additional flight testing still needs to be completed to confirm the following:
-If a quad using the higher powered Chaoli or Traxxas 8.5mm motors and the lower gear ratio of the V9X9/X2X2 will be capable of hovering when lightened as much as possibly for acrobatic flight? So far I have had problems even getting a lightened V9X9 quad not to lift off as soon as the motors start to spin. This happened when using the nQX flight controller. Hopefully a different flight controller will allow these motors to start spinning at a slower speed similar to what is achievable with a bench power supply.

-What advantage (if any) the lower gear ratio of the Alias provides in flight? Based on the plots there appear to be no significant efficiency gains using the Alias gear drive. This higher ratio must provide advantages in flight not show in the test data or the Alias would not likely have reports of such great flying characteristics. I plan to adjust the gear ratio on the V9X9/V2X2 configuration to approach the ratio of the Alias and complete direct flight comparisons between different ratios to bottom this out.

-How differently the following props fly with these geared configurations: V949, V959, GWS 5443, Traxxas Alias, and may eventually also evaluate some 5X3 and 6X3 propellers? I have never actually flown with the V959/V2X2 propellers since I find the V949 propellers particularly unstable and the V959/V2X2 are almost identical, just larger. I plan to directly compare these propellers and attempt document the flight characteristics of each on video.
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Old Oct 02, 2013, 06:58 PM
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Flight controllers:

Flight controllers:
Since many flight controller characteristics are tough to quantify (ie. Just saying one flies better than another) this section could easily become opinion based. There are however many measurable characteristics such as power output, current draw, rated power, voltage cutoff, weight, connector type, protocol, # axisÖ. Iím sure the community can think of more that would be worthwhile to include. Will populate as info turns up.
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Old Oct 02, 2013, 06:58 PM
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Batteries

Batteries
I currently have minimal interest or ability to do any extensive battery testing at this time, but realize the batteries we use are as important as the rest of the components. I will happily include any results (or link to them) that anyone would like to share.
Iíve personally gotten good but not always consistent results with Turnigy nano-techs, but have not tried a lot of different batteries. For micro quads Many swear by the 25c UDI 240-250mAh batteries, however I have yet to personally test them.
Here is a link to a great post by Jesolins

Below is a table which basically converts average current draws into an estimated flight time based on the battery size used. The table is purely theoretical and based on consuming all of the batteries rated capacity, however I personally find it helpful in quickly/roughly estimating the average current draw or flight time of a given configuration. If others think it is misleading or confusing I will gladly remove.
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Old Oct 02, 2013, 06:59 PM
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Quad / Component weights sizes and other specs

Quad / Component weights sizes and other specs
This should be a pretty straight forward but lengthy section covering the weights of the components used as well as the assembled weights of some of the popular readily available quads. A lot of the community has recorded the weights of various components so please share away. If I find a post showing the weight of something relevant, I'll link the weight result to the post it was found in. Anything in not linked will be something I measured. If multiple measurements are available the result will be displayed as a range. Thanks for any contributions in advance. I'll start with what parts/info I have on hand:

Flight controllers:
Blade Nano QX: 2.34g
Estes Proto X: 2.56g (integrates frame and arms)
Blade 180QX: 5.12g
WL toys V202: 3.4g
WL toys V252: 2.7g
JDX 385: 2.4g

Frames: (Weight, Boom size)
nQX (includes booms & protectors)
Hubsan V1 (includes booms)
Hubsan V2 (includes booms)
WL toys V252 (includes booms)
WL toys V949: 3.59g, 3x3mm booms
Blade 180QX: 5.17g, 3x3mm booms
UDI U816: 1.13g, 3x3mm booms
Vitality H36: 1.21g, 3x3mm booms (.71g without battery holder)
HCW553: .88g, 3x3 booms
Hisky FF120: 1.59-1.72g, 3x3mm booms (known for it's rigidity/durability as indicated by Daryoon Here)
V939: ??, 3x4mm booms

Booms: (Weight, Length, size, Material)
V959/V212/V222: 1.0g, 95mm, 3X3mm, Carbon
V929/V949: 90mm, 3X3mm, Carbon *Note recently some replacement V929/V949 booms arrived as 95mm length
Square carbon tubing from RC foam.com: ~8.5g, 40", 3x3mm, Carbon *Note this works out to about 1g per 120mm, and is slightly lighter due to a slightly larger through hole.

Motor Holders/Pods:
Estes Proto X: .14g (Secure motors in holes in board)
V949/V959: 3.10g
Hisky FF120: .40g (.60g including motor pedistal plug as shown here)
UDI U816:.54g (.39g without motor end cover on bottom)
HCW 553: .50g
Walkers infra-X: 1.04g, 2pcs (.5g for upper half of motor holder as shown here)
Syma X3: 1.5g
Sky Walker: 1.46g

Canopies: additional info here
Estes Proto X/ Hubsan Q4: .49g
V939: 1.48g
V949: 5.11g
V929: 3.23g
Walkera QR Ladybird: 1.4g

Motors: (Weight, Diameter, Length w/o shaft, length w/shaft, Shaft diameter, wire length)
Estes Proto X: 1.27g
Walkera infra X: , Spec sheet thanks to Ramz Innovations
Hubsan X4 H107C-A23: 5g, 8.5mm, 21mm, 24.5mm, 1mm, 55mm
Note: for motors that provided inadequate thrust results these measurements were not recorded.

Propellers:
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Below is an image showing many of the props tested for size reference.
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A different style 3X2 prop, 2.5X1 GWS style and Traxxas/Latrax Alias props are also on order and will be included when they arrive.

Gear Drive components:
Motor Covers: (typically removable)
V949/V959: 1.00g
Sky Walker: 0.23g
Syma X3: 0.10g (includes screw)

Gears & pinions: (Weight, # Teeth)
V9X9/V2X2: Gear: 0.39g, 64T Pinion: 0.18g, 11T Ratio: 5.82:1
Sky Walker: Gear: 0.83g w/shaft, 50T Pinion: .03g, 12T Ratio: 4.17:1
Syma X1/ X3: Gear: 0.68g w/shaft, 54T Pinion: ?, 9T Ratio: 6:1
Traxxas/LaTrax Alias: Gear: 0.39g, 78T Pinion, 0.18g 11T Ratio: 7.09:1

Shafts: (Weight, length, Diam.)
V9X9/V2X2: 0.42g, 41mm, 3mm
Syma X1/ X3: 0.68g w/gear, 28.3mm, 1.5mm
Sky Walker: 0.83g w/gear, 39mm, 1.5mm
Traxxas/LaTrax Alias: 0.49g (w/prop mounting screw)

Bearings: weight, size (ID, OD, THK)
V929/V949/V959: 0.25g, 3X6X2mm (ball bearing, 8 total)
Sky Walker: 0.12g 1.5X4X2mm (brass bearing/bushing, 8 total)
Syma X3: 0.01g 1.5X4X2mm (plastic bearing/bushing, 4 total)
Traxxas/LaTrax Alias: ?, 3X6X2mm (ball bearing, 8 total)

Miscellaneous components: (LEDís, Wiring, Shrink tubing, screws, glueÖÖÖ.)

Stock Quads: (weight and size (diag/side))
Estes Proto X: 11.2g, 50/35.4mm
Blade nQX: 16.5g, 103/73mm
Hubsan V1: 24.5g, 92/65mm
Hubsan V2: 27.8g , 92/65mm
Hubsan H107c: 39.4g
Walkera QR Ladybird: 23.8g
Syma X1: 47.1g

Batteries: (Weight, rated mAh, C rating)
Estes Proto X: 2.51g, 100mah, ?
v939: 10.2g, 330mah, ?
Walkera Ladybird: 8.0g, 240mah, ?
UDI U816: 8.1g, 240-250mah, ?
MJX X100: 8.1g, 300mah, ?
Mini Pet V997: 8.1g, 300mah, ?
Turnigy Q-Bot: 7.9g, 250mah, 20c
Banggood:10.5g, 380mah, 25c
Turnigy Nano-Tech: 8.8g, 300mah, 45-90c
Turnigy Nano-Tech: 8.4g, 300mah, 35-70c
Tiger: 15.3g, 600mah, 15c
Turnigy Nano-Tech: 16.1g, 600mah, 35-70c
Hyperion: 7.7g, 240 mah, 25C
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Old Oct 02, 2013, 07:00 PM
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Performance Testing

Performance Testing
Bench testing is great, but may not always translate directly to flight performance so this would be the place to share any testing of a complete quad or components actually in flight. Videos will likely be helpful here and this would also be a good place to record any quantifiable thrust/performance testing anyone manages to complete on an assembled quad. A radar gun would probably be a beneficial tool for speed testing, however using a camera and a couple markers of know distance should also be reasonable. I am thinking of roughly a 25-50 ft dash to compare speed and a liftoff test to roughly 10 ft to compare acceleration /thrust. The effect weight and wind resistance has on a quads performance could also be measured/demonstrated here.
This testing will hopefully come soon but for now Iíll toss up a video of what is currently my fastest 1s brushed quad (skip to around 1:38 for an example of approximate top speed). Edit: Since Constructing Quads using the Chaoli CL 0720 and 8.5mm v959 motors I am pretty certain this is no longer the case but will keep the video posted as is until I am able to get some comparative performance testing completed.
Nano QX nQX flight controller on a micro 22 gram quadcopter multirotor (3 min 57 sec)

On paper it looks like it may be possible to get more thrust/speed by switching to appropriate sized 8.5x20mm motors. The quad in the video weighs just over 31g with a 300mAh Turnigy Nano tech battery and should be capable of approximately 95g of thrust which yields just over a 3:1 thrust to weight ratio. By swapping to Walkera INfra X or v959 motors the quads weight will increase to roughly 36g, but should yield closer to 130g of thrust which yields roughly a 3.6:1 weight ratio. Assuming the same battery still yields a usable flight time, it will be interesting to see how much better this setup will perform.
Completing liftoff and speed tests comparing the Hubsan x4 and YD717 propellers when using the Syma X1 motor is at the top of the list, followed by testing the 8.5mm setup. If anyone has particular interest in seeing any additional comparisons please chime in.

10/18 update 8.5mm motor DD setup constructed:
I have made a handful of attempts at developing some tests to accurately compare the performance of various quads. Unfortunately with the speed some of these little quads are capable of and my outdated camera providing any decent video documentation has made this very challenging. A side by side liftoff test comparing the Hubsan x4 to the YD717 propellers while using Syma x1 motors was completed and the results were almost identical, however both took off so quick they appear as blurry dots flying upward barely distinguishable with raw full screen footage. Once any of this footage is uploaded the quality makes it impossible to see what is happening so for now you will have to take my word for it. Once I get a better camera some video documentation of this testing will be provided.

For the 8.5mm direct drive setup I ended up making one that weighs ~38.6g (with 300mah nano-tech) capable of ~130g of thrust, yielding a 3.36:1 thrust to weight ratio. A weight of 36g was predicted above however for this more powerful combination a slightly heavier frame (Hisky ff120) and motor mounts (cut down v949/v959 as pictured) were used yielding a slightly higher weight. With a fresh battery this quad wants to climb just as minimum throttle is reached so the added weight probably is't a bad thing. Again, no video documented performance testing is available however I can say this one feels quite a bit faster than the Syma x1 motor based quad. With a 300mah battery the flight time was reduced to roughly 3:00 an under, but it's a furious 3:00. With a larger 600mah battery the quad still flies great and flight times obviously increase, however the added performance is less noticeable. I realize comparing flying videos can be subjective, however one is included showing the potential until direct comparisons are available.
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nQX controlled quadcopter flying acro with flips rolls speed and crashes (4 min 18 sec)



So 7mm or 8.5mm motors for a Direct Drive setup?
Although in flight performance testing still remains to be completed, it appears that the general consensus is that both motor sizes have their merits and benefits. To sum it up, the 8.5mm motors can typically offer higher speed and carry larger payloads but also fly heavier and don't respond quite as quickly as a good 7mm motor based setup. Benedikt and myself discussed many of the differences and advantages in posts here, here and here.
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Old Oct 02, 2013, 07:00 PM
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Other testing, modifications and observations

Other testing, modifications and observations
This section will be reserved for performance testing results and personal observations that cannot be necessarily obtained with technical measurements. Modifications that do not fall into a specific section will also be included here. Much of the motor/prop performance testing will fall into the post related to that particular motor/prop size. There are however other factors such as the effect of frame size, effect of motor holder orientation, prop balance vs. thrust, COG vs. agility,….. that may not fall into a particular section or be tough to quantify.

Effect of prop wash / prop orientation
The effect propeller to boom distance and the motor/prop orientation has on thrust is often discussed. After reading some of this thread I got inspired to do a couple of tests to see the effects these factors have on micro quad thrust using my little test setup. I put together an image showing the 4 orientations tested. For the last 2 orientations I had to use a ccw propeller on a CW motor and also had to drill the prop hole all the way through to orient the prop upside down. All testing was completed using a Syma X1 motor with a Hubsan X4 prop. The graph below shows the results, labeled as indicated in the image. In a conventional setup, moving the prop away from the boom arm increased the maximum thrust by approximately 4%. Placing the propeller below the boom arm increased the thrust by approximately 8% more. The prop to boom distance had much less of an effect when configured like this. It looks like I am going to have to try to make a pusher/inverted style quad now too.
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With motivation from the encouraging bench test it didn't take long to construct the following:
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After flying this quad a handful of times I am finding it more durable than expected but still not as durable as a conventional setup. Some side by side performance testing against the same components in a conventional setup is needed. Until that is completed I will include a video attempting to show it's potential. I find the change in prop sound quite surprising.
Blade nQX controlled micro pusher prop quadcopter flying aggressively with flips rolls and tricks (4 min 31 sec)


patricklupo used a similar configuration for an FPV setup shown below from this post. The setup also features a micro landing skid which looks pretty nice.
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Going on a diet, removing & reducing components for even lighter weight:
If reducing the weight of your quad is of interest on top of using the lightest components, below are a few modifications to try.
An inspirational thread dedicated to making the smallest/lightest quad possible started by Dave1993 can be found here. Additionally a very lightweight quad using the Hubsan X4 FC by RDaDDiCT! can be found here, and a very lightweight quad using the nQX FC by Derk can be found here.

Removing canopy: This is rather obvious and typically very easy, but can yield surprising weight savings and also noticeably reduce wind resistance. Post number 8 includes some canopy weights for reference.

Shortening motor wires: Some slack should be left in motor wires, however some motors are supplies with wires significantly longer than needed for a particular quad. Below is a picture showing how much wire was removed from 4 Syma X1 motors while still having enough length to construct a micro quad.
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Removing motor wire plugs: This will require soldering, however a consistent weight savings of ~0.4g can be gained by removing the motor wire plugs on the FC board and motor wires. This is using the small connectors on the nQX FC board. Other boards may use more and/or larger plugs allowing for even greater weight savings.

Ditch the screws: Metal is heavy and not really needed for securing things on a 1s micro or mini quad.

Hot glue and other adhesives are your friend: I personally use tiny amounts of hot glue to secure any loose motor mounts and thin strips cut from double sided foam adhesive to secure the FC board to the frame. 3M super weather strip adhesive was recommend by Siriuflier as show in this post and Jesolins mentions use of a few other adhesives in this post.

Rubber bands as battery holders: Allowing you battery to move in a crash can really add to the durability of your quad. This is especially true when the battery makes up approximately 1/3 of the flying weight of a quad. Additional strain relief is recommended on battery wires as they will be moving more in a crash.

Eliminating a separate main frame component:
This requires using Velcro, rubber band or other method of securing the battery but can result in a lighter and very rigid one piece frame. An image is provided showing how I've constructed mine so far. It's a pretty straight forward concept but figure a few images and a bit of explaining may be worthwhile. Basically the frame starts with 2 square sections of CF tubing (95mm v959 booms shown). A notch is made in the center of each as shown in #1. For this one must take care to avoid breathing any dust if using CF. A ~3mm wide piece of wood wrapped in sand paper was used to file away the notches shown while held under running water. A slightly sloppy fit is okay here. The frame is then squared up and tape is used to temporary hold the squaring. The assembly is then flipped over, crevices are filled with baking soda and flooded with CA glue. Once dry the taps is removed and the other side gets the same treatment. Thread is then tightly wound around the joint and covered in more CA glue to keep things secure. FC boards can be secured to double sided tape which gets hot glued to the frame/booms. Results in a pretty light one piece frame. Obviously other securing methods are possible and I'll post any more suggested/shown.
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Removing/reducing motor holders:
Stock motor holders are not particularly heavy (as light as ~0.4g for Hisky FF120) however these motor holders can typically be reduced further for even greater weight savings and still remain functional. See the image below to see how the Hisky FF120 motor holder can be reduced down to below 0.2g each. The lightened motor holders seem to be slightly less durable, however they are very inexpensive and seem to perform just as well when in the air.
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Micro brushed motors can also be mounted other ways using material and methods available at home. While these methods are not as durable as readily available motor holders, they can offer worthwhile weight savings to those willing to make some durability sacrifices.
Direct side mount: Super glue and thread can be used to secure motors as pictured
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Direct base mount: As suggested by Flying-llama the base of each motor can be secured directly to each boom using hot glue. CA glue was used to secure each motor and then reinforced with hot glue as pictured. Unfortunately this method did not turn out to be very durable for me and I ended up with the second image pretty quickly. Additional hot glue may have stopped this, however any potential weight saving (vs. a cut down motor holder) will be lost if too much glue is used. Others may be more successful with this method.
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Removing motor covers: This mainly applies to Gear drive quads but can provide surprising weight savings on certain quads. Typically motors stay in place without these covers or can be secured using much lighter materials. See the motor covers in post 8 to get an idea of the weight savings possible.

Cut down landing skids: This also mainly applies to geared quads as well and can lead to further but minimal weight reduction (<1g total). These landing skids typically raise the gear assemblies of these geared quads off the ground a bit so gear drive components may wear faster if the quad isn't kept in the air.

Modifying propellers to fit on different size shafts:
0.7-0.8mm propeller hole onto 1mm shaft:
1mm propeller hole onto 0.7-0.8mm shaft: Video Coming soon
GWS 5443 on Syma X1/X3 hex shaped shaft:
Installing GWS 5443 propellers on a Syma X1 or X3 quadcopter drive train (4 min 1 sec)


Changing the gear ratio on a gear driven quad:
More details will be provided in the future, however here is a video on removing a pinion from a micro coreless motor for now.
Removing a pinion from a coreless micro brushed motor (0 min 45 sec)
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Old Oct 02, 2013, 07:01 PM
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Pics/videos and stats of your custom or modified quads:

This will be the place compile stats on custom built or modified quad(s). Please try to include at least 1 pic of your quad and the following info: Size, Weight, all components used and any modifications made to them. Including flight times and batteries used could also be helpful

From Sofo:




From Siriusflier:
From top left:

H107C - 39.9g ...... V252 - 25.7g...... JXD385 - 24g
2 V929 motors ...... stock motors ...... stk mtr, 1 bad

V202fc - 32.5g ....... V202fc - 27.0g...... V202fc - 24.1g
V929 motors ...... syma X1 motors...... X1 motors

V202fc - 24.0g ...... V252fc - 21.5g ...... V202fc - 21.5g
Chaoli 0720s ....... Chaoli 0720s ....... C0720/X1 +balsa
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Old Oct 02, 2013, 07:03 PM
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Extra post in case another section is needed

Just because I didnít take up enough space already. Seriously the thread is a big mess right now but hope it will eventually become something helpful/useful to reference.
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Old Oct 02, 2013, 11:15 PM
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Wow! You ARE the man!

Thanks, Dave!!
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Old Oct 03, 2013, 02:00 AM
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Quote:
Originally Posted by woodsturning View Post
8.5 motors are typically used on geared quads but at least one uses a direct drive setup.
...
Direct drive:
Walkera QR Infra X
Hubsan H107C and H107D?
I have read somewhere that the Hubsan H107C and D motors are literally 8mm motors and so "in-between" 7mm and 8.5mm motors.
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Old Oct 03, 2013, 02:11 AM
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Bravo !!!!!

Amazing work
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