motor and prop for 5 inch 5 minute flight time quad?

[MegaMech]

Hello,

I'm hoping to make a 5 inch quad with around 5-8 minute flight time.
My brother and I will be racing each other, but we don't need 200km/h speeds. We'll make some kinda track and have identical quads. FPV.
We won't be using go-pros. Perhaps the split cam.
For battery I'll try to find the most optimal choice between flight time and power output.
We'll have extra batteries.

I'm considering this Armattan mongoose frame because it weighs 61 grams. It's a little weaker than heavier frames, but because we're going a bit slower it may survive some crashes?
https://www.rotorvillage.ca/Mongoose-p/frame-ar-mongoose.htm

Perhaps this emax eco 2207 at 1700KV?
https://www.rotorvillage.ca/EMAX-ECO-2207-p/emx-eco-2207.htm

This motor recommends: EMAX AVAN Flow 5x4.3x3 Prop, but should I go duo-blade rather than tri-blade to reach a longer flight time?
Would I sacrifice too much maneuverability?

Going 3 Inch quad is also an option. I just feel it's kinda too small, and the 5 inch would be more fun.


Thanks for your advice in advance.

 

[PsyBorg]

Racing and longer flight times do not exist. Unlike freestyle you will be into the throttle more steadily which is what eats up amps and thus reduces flight times.

I am a huge fan of emax motors. They can however suck some amps when improperly propped.

I have tried the avans on both my 5 inchers and a 2 inch gremlin. Cant say Im a fan.

You are going with low kv motors so designing around 6s set ups could get you into 3 to 5 minute "race" range.

Running weak props like 5x4x3 will reduce amp draw and give better cornering but top end speed will absolutly be boring to race with after a few months.

You may get the flight time you want at first but once your skills improve and your avg speed rises you will drop down in to that 2 min flights per pack range fairly quickly.

As for the splits or other similar cameras dont bother. They maybe ok on the hd side but for being abke to see when you fly they are absolute garbage in anything less then perfect light.

The separate run cam dvrs will do nicely for race footage to track progress or see where you need improvement. Again.. another thing in the quad drawing already limited available power.

 

[MegaMech]

Sorry for the long delay,

Thank you for your suggestions

What do you suggest for motors? Cause last time I posted about the limited edition emax 2306 whites and people were like "You don't understand what you're doing" and "You're building too big". So this time I looked a bit smaller.
Price isn't really an issue for performance vs economic motors they're all dirt cheap.
If building for time isn't possible, than I might as well just get the biggest motors I can?

 

[FDS]

Have you decided on a battery voltage? 4 or 6s?
Then it’s a matter of how much you have to spend, how fast you want to go and what features you want, like rebuild able motor bells with spares or similar.
Have you bought any parts at all?
There have also been a number of very fast, capable and relatively cheap ready made 3” race quads released this month and last, as the interest in them increases. Many are 6s and very fast.

 

[MegaMech]

probably 4s. I'm building a quad, not buying a crappy prebuilt incase that wasn't obvious enough. If building for time isn't possible than I might as well go big. But I dont necessarily need 200km/h speeds.

 

[FDS]

Have you bought any other parts? What frame are you considering? Are you definite on a 5 inch?

 

[MegaMech]

"Have you bought any other parts?"
Irrelevant.
"What frame are you considering?"
Scroll up.

These open source TBS frames are cheaper than the frame I was considering above. The TBS source 1 is a freestyle frame but is advertised as being able to survive lots of crashes. Since we're just racing for fun, would it be better to get the freestyle frame than the racing frame? (Because it breaks less easily) If one day we decided we needed to go faster we can always upgrade the frame later.

https://www.rotorvillage.ca/TBS-Source-Two-p/frame-tbs-source2-v0.1-5in.htm

https://www.rotorvillage.ca/TBS-Source-One-p/frame-tbs-sourceone-v0.2-5in.htm

I think this is a pretty simple question... Should I consider any motor sizes other than the 2306 for a 5 inch quad? Battery and frame is irrelevant. In a purely performance perspective that the emax 2306 sucks up power and goes extremely fast. Should I consider perhaps 2205's or the EMAX ECO 2207 or similar?

 

[FDS]

I like the TBS Source One. Mine has been very tough, you can get new arms and it has plenty of room for gear. Mine tops out at about 60mph (best guess) on 4s with T Motor LF40’s and 5040 props.
I am not a fan of the Emax motors, they suck current and for a little bit more money there are more efficient and better built options.
The Source 2 has less space on board and isn’t quite as adaptable, it’s designed for a more compact build. I am sure the quality is as good as the Source 1.
Other parts are NOT irrelevant in motor or frame choice. For example if you have a large 30x30 triple height stack and 4:1 ESC combo, that isn’t going to fit in a small race type frame. Likewise you can have very nice motors and if you hook them up to a garbage ESC and FC combo your flight experience is going to be poor.
Many race frames feature narrow profile arms, which need matching ESC’s if you are not using a 4:1.
Good builds are about balancing your components so that the whole ensemble can be tuned together to work well.