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7 inch 6S long range prototype

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The Idea: 7 Inch hq 7×3.5 V1S
360mm streched X frame
2207 1700kv motors
Lumineer 50amp 4in1 esc
Dshot 1200 esc protocol
F7 Kakute FC (soft mounted)
Betaflight 3.5.6 or 4.0 if released
6S 1500mah 75c
Runcam swift 2
2w (2000mw) 2.4ghz vtx
900mhz 2w crossfire TX & RX

It's a long range prototype.
This is a recycled Idea from my past. Tried building a 7 inch 4S a while back. A 4S pack with enough energy density to swing 7inch props for more than a minute or two flying acro doesn't exist on planet earth. Now that 6S in commencement I reconsider building another 7 inch. I still have most of these parts minus lipos, esc and motors appropriate for this endeavor. Considering the parts listed above, any thoughts?

I'm buying this nearly $100 4in1 esc, exorbitantly priced lipos and the quite expensive motors after I pay my rent for next month. I write this thread with the hopes I might learn something from anyone who has thought outside the 5 inch box. I'll still build and fly my 5 inch quads but I started years ago modding my phantom and flying a couple miles away and back without losing control signal before I saw the light and began building 5 inch to fly acro mode. Wouldn't it be great to fly acro with a more efficient quad having battery life and range to explore?
 

RENOV8R

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Hmmm, may be the combination of motors and those power sucking HQ props which resulted in your short flight times. I'm flying a 7" iFlight XL7 V3 with Radix FC, BH Avenger 2507 1500kv motors, 35A Emax Pro ESCs with Genfam 7042 2-blade props and getting 8-10 minutes with a RDQ 4S 100C 1800 mah lipo. I'd suggest you input all your components into eCalc - the most reliable electric Motor Calculator on the Web for RC Pilots to get an idea of amp draw and flight times. You can test different motor/ESC/prop combos without actually having to spend any money
 
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I built my prototype. It actually flies better than I had imagined despite some gyro noise I've had difficulty filtering. The prototype battery is much smaller in capacity and weight than I intend to use for the final version. However the form factor and weight distribution has a perfect cg, com, and is very slim for minimal separation of mass since is essentially layers the top of the frame in its entirety. The prototype I built cheap for fear of problems and to reduce cost and allow better budget for V2. The 7x3.5x3 V1S's are swung by Brother hobby R3 2207 1660kv's on 6S 1000mah Tattu 75c. Pyro-45amp blheli32 4in1 esc (using dshot 600 currently). I direct soldered a 1000uf electrolytic cap on the esc source terminals and a 680uf cap on the battery connector for smooth power with dampened transience. Aikon F4 running 8khz gyro sampling because 32khz would raise the noise floor to my disadvantage on this build. 8k/2k has yielded decent flight. The motors and stack is soft mounted on an FPV King QL7 296mm frame. Prop direction is reversed. BF 3.5.6
Runcam swift 2, Akk infinite LR edition with DVR 1000mw. Gyro noise is the main issue.
V2 will consist of the same fpv eq. Same frame, same soft mounting practices. Same test lipo (for tuning stage only). 7x5x3 Gemfan props swung by 2506 1250kv on 6S. 45amp Hobbywing xrotor blheli32 4in1 esc, brainfpv raddix FC with Bosch Gyro. I expect better gyro noise floor profile for better tuning and equivalent if not more thrust and superior torque constant/amp efficiency. These are just theories. It may pan out differently but this is how I will build V2 this weekend although V1 flies well despite low throttle gyro noise. If anyone has any info I love to research, tune, learn and build. Any input is appreciated.
 
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It's probably worth saying. It's fast, very.
Handles far better than expected.
The Bosch gyro on the brain fpv raddix I'm buying should help improve upon the low throttle gyro noise issue I'm currently unable to filter on V1. V2 will surely benefit from arguably the best gyro for the noise profile of this quadcopter build. If nothing else, I learned one thing. 6S if used properly had thermodynamic and performance benifits. I appreciate any input. I hope someone out there might know something that could help educate me to better achieve my goal of a well tuned 6S 7 inch LR acro quad. Very familiar with bfbb logs and using those logs for tuning. It's just difficult when the pid loop cant tell the difference between gyro noise and angular movements. Thanks!
 
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RENOV8R

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What?? All that and no photos?? lol. You'll be amazed with the Radix, nothing on the planet can touch it for performance and reliability. And as far as gyro noise goes, it shouldn't be much of an issue but if it is, the Radix has what they call the spectrograph feature so you don't have to mess with blackbox logs any more. If you go to Youtube, one of the BrainFPV pilots has a great video on how to use the spectrograph
 
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What?? All that and no photos?? lol. You'll be amazed with the Radix, nothing on the planet can touch it for performance and reliability. And as far as gyro noise goes, it shouldn't be much of an issue but if it is, the Radix has what they call the spectrograph feature so you don't have to mess with blackbox logs any more. If you go to Youtube, one of the BrainFPV pilots has a great video on how to use the spectrograph
15545875952845231244385588783321.jpg
This is the 7inch prototype.15545875952845231244385588783321.jpg
This is the 7inch 6S prototype V1.
 
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15545888701896444894440950970054.jpg
The 7inch 6S prototype V1 is my favorite acro quad I've built so far. V2 will be even better I hope. Just waiting on a frame and esc to be delivered.
 
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155458919498729457724214685702.jpg
I have high Hope's for the Brain fpv raddix and the 2506 1250kv motors I bought for V2. It will use the same 300mm stretched X frame as V1, same Akk infinite DVR LR edition VTX and same Runcam swift 2 as well. Just waiting on the frame, Gemfan 7056 props and the hobbywing Xrotor blheli32 45amp 4in1 esc to use with the raddix FC I bought. Then V2 will be built.
 
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Anyone out there built a 7 inch 6S they had success with? V1 flies well except a little gyro noise the SW LP and notch filters in BF 3.5.7 won't get grid of. I think the Aikon F4 I'm using would be better for a 5inch. I really hope the Bosch Gyro in this raddix I bought for V2 yields better results.
 

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