Building a X180 Quad - Help is needed

[Trimitsos]

I am interested in building one X180 quad.
I have concluded on size (x180) and frame models (tweaker FPV or Goby-180) and Flight controller as well (Dodo rev 3a).
I would really like your help on selecting compatible parts such as motors, props, batteries, ESCs

ESC= LittleBee 20A ESC (BLHeli)?
Motors= EMAX RS2205 2600KV not concluded on this yet, but something 3S-4S compatible
Props = Something to go with the relative motors/battery but would like some set of 2-blade props and some set of 3-blade props.
PDB: like "Afro Power Board" or a similar one (since dodo FC has an embedded regulator)
Batteries: 45C-75C 3S & 4S (1000-1300mAh)


I will really appreciate any help, since I';m stack for a long time now!
Due to the fact I am a beginner and all the above have come to me from forum/internet reading, I would really like to hear your expert opinion on the above selected parts.


p.s.
I already have already built a micro FPV 5.8G system, waiting to be used...

[Cheredanine]

Building Tweaker myself at the moment,
Thoughts:
Flight controller - the best at the moment are f3 boards which can run spi to the sensors, this means lumenier lux, motolabs cyclone or tbs powercube.
The first two are difficult to get hold of and e latter comes with fixed ESCs BUT you are in luck, the lux (which has the best form factor of the three) is just coming back into stock in uk, radioc got it over the weekend, expect hobbyrc and buildyourowndrone to be not far behind. Get it whilst you can, they tend to only be available for a very short period

Motors - the eMax are great for sling around high pitch 5 inch but on a 180 they are heavy and don';t give you any real benefit (they are carrying the capability for loads more torque than you will ever use and you pay for in in weight) fast 1806s will work well with a light build, I am using rg2205 2700kv which may sound similar to the eMax but are designed around 4 inch props

ESCs - littlebees will work fine although silabs f390 based ESCs would be better for high kv motors. Best of all would be kiss24a running oneshot42 but difficult to get hold of, again personally I am trying some experimental firefly ESCs which are also oneshot42 capable

Pdb- like the Birdseye/thugframes v1.2 as it gives a secure and light xt60 and the options of mounting pololu step downs (don';t forget if you fly fpv you will need something for the vtx and possibly the camera) - mine will be using an RRpro osd/pdb

Batteries, planning to run graphene 4s 65c 1000mah, weight is important, better to run 1000mah than 1300 if it can cope

Note- I will be running the most aggressive 4 inch props I can find, suspect 4045bn triblades

You need to balance motor/prop/esc/battery combo, there are lots of options but your current spec is just too vague, suggest you change your motor choice, decide if you want to run 3s or 4s, confirm if you are sticking with littlebees (which as I say, are fine), you can then look at some thrust tests with different props, this is a very good resource:

http://www.miniquadtestbench.com/about.html

[teslahed]

This 180 miniquad is on 2600kv 1806 motors and a 3 cell LiPo;

http://youtu.be/m908mp0-ATQ

http://rctimer.com/product-1571.html

It seems more than fast enough for me at the moment.

Going larger than 1806 motors on a 180 sized quad will turn it into a total rocket ship that will use a lot of amps at full throttle and probably give you 2 mins of battery life if you are lucky. I am sure that could be a lot of fun.

Depending on your flying style and where you are flying, more power isn';t always necessarily better. A lighter quad will fly more nicely in smaller spaces and will be more manoeuvrable. It will use fewer amps in the hover and so fly for much longer. If this is your first quadcopter building the fastest possible aircraft may not be the best idea either.

I would suggest 1806 motors as standard for a 180 sized quad, smaller motors if building particularly light and heavier ones only for a total rocket ship. If you don';t want the fastest aircraft possible don';t fly with larger than necessary motors because you';ll be wasting energy carrying that extra weight and your aircraft will fly less well when it';s not getting to take advantage of the extra available power.

[nub]

the extra weight can also mean more damage in a crash, i';m running 1806 2300kv';s on 4S with tri';s and it';s got a no bad wee bit of a poke ::)

[teslahed]

the extra weight can also mean more damage in a crash, i';m running 1806 2300kv';s on 4S with tri';s and it';s got a no bad wee bit of a poke ::)

My first 180 had 1306 motors (now moved to the 130 micro quad) and was a little underpowered. I then upgraded to the 1806 motors I used now. I don';t think I will upgrade it again because I have a 250 that will always be better for speed flying anyway and there is no point having 2 quads that are too similar and both good at the same thing.

I can well believe that in terms of KV, 2600 is best for 3 cell and 2300 best for 4 cell if going 1806 on a 180. It';d be interesting to do a direct comparison of those 2 setups but I can imagine they are fairly similar.

[nub]

drag race!

larger motors would be interesting, i think the prop your thinking of using is quite important too, something i noticed about HQ 4" tri';s was they are heavier than the DAL';s and it has kind of put me off using them, this may be when the larger motors with more bottom end grunt may be a better choice, personally i think the 1806 may struggle a little with the HQ tri prop.

[Jazzz]

Can confirm to big motors a lot less flight time
I just put 2206 motors on a 230 size quad that previously had 1806 motors on the 1806 gave 5 minits fast flying
The 2206 only give 3 fast flying  and with the extra weight
And speed you need a much bigger place to fly .

[Trimitsos]

Thank you ALL so much for helping out, I really appreciate your input

@Cheredanine
FC: What do you thing of "DODO" FC versus "lumenier lux" – I am kind leaning towards the DODO for some reason, do you have any negative info on this FC?

PDB: For the same price <5$, I would go with this: http://www.hobbyrc.co.uk/matek-mini-power-hub-v3-pdb-5v-12v-bec it has two embedded regulators 5&12V but no XT-60 plug

ESC: For a start I think "Littlebees" will be more than fine price-wise & weight-wise

@teslahed - Thanks for the Great TIPs!
Motors: I agree on the size, after watching your video above, I am confident 2300/2600KV 1806 motor will be more than enough for me. Flight time is important to me (target 5-6 min), rather than speed!

Battery: I am a little bit confused about choise of 3s or 4s battery in conhuction with 2300KV/2600KV – Which one goes better with  what??? I am thinkg of building with 3S batteries (but also with 4S capability)

[Cheredanine]

Hi,
Lux has a better form factor than dodo, also runs spi to gyro, allowing a much higher loop time, removing aliasing and making gyro more accurate

Pdb, cool, I have used matek before on a 180, although not that one

Battery: 1000mah or 1300mah at most, anything else will be too big/heavy, 4s will be quicker than 3s, watch your c rating, on 4s you may need as much as 60-80c for punch out on a 1000mah battery

[Trimitsos]

So does it matter if I chose 3S battery with 2300Kv or 2600Kv motors???
And what happens if I later use 4S with the same motors?

[Cheredanine]

The kv of the motors is (and this is only a rough guide) the rpm per volt it should spin at.
Assuming 4.2volts per cell for a fully charged lipo, a 3 cell battery has 12.6volts, a 4 cell battery has 16.8 volts

So for a 2300kv motor it is designed to spin up to 28980 rpm or 483 times a second on 3 cell
And 38640 rpm or 644 times a second on 4 cell

In theory then the 4 cell is much faster, turns and manoeuvres quicker etc

HOWEVER

1. A 4cell will draw more power to get that faster spin, this will reduce your flight time
2. 4 cell will draw more power (again), your battery needs to be able to provide enough amps for it to do this, (see point 3 below)
3. Having props on a motor create load. The motor draws more power to generate torque to cope with that load. (See 1 and 2 above). The bigger, more aggressive pitch and heavier the prop, the more power the motor will pull. If the props are too aggressive, this is referred to as over-propped, the efficiency of the motor (grams of thrust per amp) starts to drop, eventually the motor or esc will overheat or burst into flames, or the motor will not be able to generate enough thrust (generally because the battery can not provide enough amps)
4. As the motor power draw goes up because you open the throttle the battery will start to struggle, it';s voltage will sag with a corresponding effect on the rpm


So what does all that mean?

Well the best thing is to find some static thrust tests somewhere you trust (not the manufacturers - mini quad test bench is a good source, but don';t think he has done 1806 motors), look at the motor and prop combination you want, on a battery cell count you want and take a note of the amp draw.
If the combination you are wanting is inefficient, then you are probably going to be over propped (load in flight is more than that on the bench)
Then make sure your ESCs can cope with the amps.
Then make sure your battery can cope with the amps (multiply the amp draw of the motors by 4. Compare to the mah x the c rating /1000 of the battery. But be aware all battery manufacturers exadurated their c rating

For example, my last quad has xnova2204 2300kv motors, I am using hq5040 triblades, that will mean the motors pull a little over 20amps at full throttle. 80 amps total.
I am using graphene 1300mah 65-150c 4s, so they provide 1300 x 65 / 1000 amps or 84.5 amps constant and more than double that burst.  Of course that will be exadurated but I am still comfortably pulling less amps than the battery can provide.  I am also using 24amp ESCs.


The alternate is to find an existing setup someone already runs and use the same BUT there is a lot of over propping at the moment

For my old 180 I ran dys 1806, dys bl20a ESCs, 4s 50c 1000mah batteries and 4045bn props, it works. Not sure I would have put 4045bn triblades on them though.

[Trimitsos]

your answer includes so much info.... I hade to do some studying....
Thank you Cheredanine

[Trimitsos]

I am having a difficulty in finding a european supplier for the Dodo Flight Controller.

So I';m thinking of going with something like:
Seriously Pro Racing F3 SPF3 Deluxe Flight Controller

https://buy.4props.com/flight-controllers/spf3/seriously-pro-racing-f3-spf3-deluxe-flight-controller.html

What do you think?

[teslahed]

The SPF3 is a good board which will support the latest features with the F3 processor.

For your first build I doubt you';d notice the difference between that and a £15 Naze32. Unless you make a mistake and fry something in which case you';ll wish you started with a £15 naze32.

[Cheredanine]

Agree with teslahed, spf3 is fine, my favourite FC of the day is the lumenier lux, but tbh a naze will be fine