Video recording.
I hope to be able to carry it (disassembled) without batteries to Nepal, get to vape shop - and buy vape batteries (which are available everywhere now thanks to smokers).
Waiting for ESCs.
I screwed up both 4-in-1.
The problem that in my location hobby shops sell 5 times the online price and I cant get any soldering supplies.
Its problen to solder 12AWG without flux pen and normal soldering station…
Even I know soldering fairly well.
So ordered 8 F35A T-Motor ESCs instead…
Plus soldering supplies.
Some horror story:
Today I went to hobby shop in Dragonmart - a HUGE China mall in my city.
There is one hobby shop specializing in larger drones as well.
So basically they were parting out some drones of another hobby shop which shut down few years back.
They had a box with many ESCs and motors.
We picked up 8 second hand RCTimer SimonK 40A 6s ESCs.
And started to discuss the price.
They “checked the price” and told me first 32$ each, a ridiculous price although I warned them that I know prices well.
32$ is even more than price of same new item online.
But this is 7+ years old tech. No dshot no anything.
And its second hand item.
Than they went down to 23$. Its still more than F35A Blheli 32 T-Motor brand new!!!
And these were second hand!
And they didnt go down more.
So I left that shop and ordered 8 T-Motor ESCs on Aliexpress.
Is it all retail hobbyshops are complete heist? Or only here it is so?
Some projected results:
Optimal Speed: 60 km/h
Range: 8km
Hover time: 15 minutes
I think you will get ~7 minutes, if you are nice to your batteries, and leave at least 1 minute for emergencies.
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I thought so too, mate!
But I was surprised today when I finally paid for Ecalc full version (3$).
It gives 17 minutes hover.
But whats more important - these 880kv motors give higher speed (60km/h) than 300-400kv (35km/h) and thus have same range - 8km.
It seems this setup will be viable…
8km is good enough for my filming.
Plus the battery case weights a lot and the aluminium frame.
Let’s see how it will work out, the 1147 props are on the way. These Sunnysky motors are great.
With your heavy construction, small props and high KV motors, I just don’t see 15 minutes happening, but with be very happy to be wrong 
Did you remember to choose the coax setup?
Your g/w value is then 4500 grams / 915 watts = 4.92 g/w. That is very low indeed.
But let’s see it fly soon, then we’ll know if ecalc was drunk (has happened before 
)
200 g/w is at hover.
Thrust to weight is around 2:1.
Its a bit underpowered.
The 200 value is W/kg, basically how many watts is needed to lift 1 kg.
The g/W I mentioned is the other way around, and the usual way of expressing efficiency in drones.
Bro I believe its hover efficiency, right?
This one is less efficient in hover but more efficient in range (due to higher speed).
Makes sense?
What you will gain in better efficiency from forward flight will be almost nulled by the higher RPM needed to go faster. So maybe an numeric increase in g/W of 10% max.
Sorry I wrongly expressed; it will be less efficient in hover but same (not more - I said it wrongly before) efficient in range as slower motors.
Makes sense?
Other than that - I have some updates - the rig will loose some weitght by optimizing battery mount.
Final battery pack will be 4S7P.
Alright the things are getting serious now.
The construction is rigid, tight and solid as a monolith.
Minimal freedom degrees on all axis.
Camera stand avoids the prop wash and props line of sight - and it does not vibrate, flex or twist itself at all.
Batteries are fixed with minimal weight of mount and secured very well.
Just need to attach ESCs (arriving next week), Navio 2, landing gear - and ready to fly.
(landing gear is temporary and lower 4 motors temporary removes).
PS: my idea of switch to warm up and get GPS fix was already realized by Christian Mauch (Mauch Electronics) - in a smart way using digital switch and PDB with soft power up of ESCs (which as per my understanding will not need extra capacitors). That person is a genious.
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Look at my works, ye Mighty…
Current weight: 4000g.
Only needs ESCs and can fly.
All else is done, except software configuration.
Great stuff, I’m looking forward for the test flight and the report how much A is needed to hoover your tank and how much additional weight it can carry 
You have used an interesting power module. A little bit heavy and expensive for my tasks, but great stuff.
What I wonder is where the isolation of the connectors are gone?
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Thank you so much @tobias-dahms!
The shrinking tubes I didn’t install yet, will do so shortly, as well as the wire management.
This power module/PDB as per my understanding has protection against inducted voltage on longer ESC wires to save the ESCs and avoid the need to put extra capacitors on them.
I.e. soft power up.
This is a nice feature, though I might ve misunderstanding something and this needs double checking.
So, how did it fly?
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Still waiting for ESCs, they arrive this week.
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