Hi all,

Looking to get into FPV. I have no other RC gear. I have a heavily modified diy 3d printer and have built dcircuit boards so am very comfortable with soldering.

Have been sim training on Xbox controller while I wait for my RadioMaster Pocket ELRS to arrive.

I would like to build a 3.5' FPV drone. I live in New Zealand, and will probably buy from GetFPV as they have reasonable shipping rates internationally.

I don't think I'll get into racing. Maybe some tricks in the future, but mostly cruising. I live rurally so have wide open areas to explore. That being said I do have a couple of neighbors within around 50 - 100 metres away so don't want anything too loud, hence the 3.5' size.

The budget is around $250 USD. Can go up if really worth it. I want to get a fairly decent setup and not have the itch to upgrade for a while. For now, I think I just want to focus on the drone minus the camera system/googles. Will work that out later, however this is for hobby, I don't need to be mounting a GoPro to it. So the $250 is just for the Frame, Motors, ESC, props etc.

I want a fairly decent flying time, ideally around 7-8mins + when not pushing it hard (which I def won't be at the start).

For the frame, the Grinderino looks decent, though a bit heavy (but durable), will the extra weight limit the flight time a lot? I will purchase some extra arms.
Can anyone recommend decent motors, ESC and props etc? Everything for the drone itself required minus the camera system, batteries and goggles.
I have read that the Aerolite 2004s motors are really nice, but am having trouble deciding on 4s or 6s cell battery, and matching the motor to that size.
Have no idea about recommended props.
For the ESC, I was thinking something like SpeedyBee F405 V4. Is that a good option?

Thanks

Motors wise, you could get away with 1507's on 6S, 1804's on 4S and yes you could do 2004's on either battery size, but the build would be seriously OP and possibly a complete nightmare to tune. I've seen videos of people flying on 1507 on 6S that would be fine for me in terms of power and 1804 would be very powerful.

1404 on 4S


1507 on 6S


1804 on 6S


2004 on 6S (3" frame)


Another possibility is you buy a set of 1404 motors and fly it on a less powerful setup for 2-3 months while you actually learn to fly it IRL. If you use MR30 connectors when you build the quad for connecting the motors to the ESC's, you could swap out the motors for something more powerful, down the line, once you have your flying up to a good level.

(02-May-2024, 03:37 AM)Pathfinder075 Wrote: Motors wise, you could get away with 1507's on 6S, 1804's on 4S and yes you could do 2004's on either battery size, but the build would be seriously OP and possibly a complete nightmare to tune.  I've seen videos of people flying on 1507 on 6S that would be fine for me in terms of power and 1804 would be very powerful.

1404 on 4S


1507 on 6S


1804 on 6S


2004 on 6S (3" frame)


Another possibility is you buy a set of 1404 motors and fly it on a less powerful setup for 2-3 months while you actually learn to fly it IRL.  If you use MR30 connectors when you build the quad for connecting the motors to the ESC's, you could swap out the motors for something more powerful, down the line, once you have your flying up to a good level.

Thanks for that info.
These motors are well reviewed: https://www.getfpv.com/checkout/cart/con..._id/12749/    (iFlight XING2 1404) I think the 4600KV would be best? Though the mounting pattern is 9*9, and the frame supports 12*12, so they wouldn't be compatible?

(02-May-2024, 02:15 AM)mintjberry Wrote: ...

I want a fairly decent flying time, ideally around 7-8mins + when not pushing it hard (which I def won't be at the start).

For the frame, the Grinderino looks decent, though a bit heavy (but durable), will the extra weight limit the flight time a lot? I will purchase some extra arms.

....

Hi Mintjberry,

For a cruiser, I would consider Pathfinder's suggestion of using 1404 motors 
with connectors. The battery size (voltage = cell count) will sort of determine
what KV you need. There is one thing that I will throw out there. Consider 
that motors with a little higher KV for say 4S, can always have the KV limited
with Betaflight to better run 6S packs, but you can't go the other way. With
motors that are appropriate for 4S, you could also use a 4S Li-Ion pack which
is a standard for 4 inch Long Range quads. You get the best fly time with 
a higher Energy/weight (mAh/grams) for any given battery weight allowance.

I know that 6S is all the rage, bigger, more voltage, faster acceleration, etc. 
which is good for the ACRO stunt pilot or racer. However, 6S batteries are
also heavier than lower cell count batteries. Yes, weight does make a difference
and often requires bigger (yet, heavier) motors. I guess if one is not concerned
about the weight, then it doesn't matter...or does it? 

My focus is on the sub-250 gram, FAA category 1, UAS (drones) and flying
them solely and purely for my own recreational fun so that I can legitimately
utilize the Recreational Exemption where sub-250 gram craft are not required
to be registered and not required to have Remote ID. The sub-250 gram weight 
is the AUW or Maximum Gross Takeoff Weight including the battery and all 
payload.

Personally, I want to stay within the FAA regulations. I am not a rogue player
and try not to intentionally violate the laws and regulations. With that, 6S 
batteries really have no place as they are just too heavy. Of course, if you are 
going to fly a "heavy" then it doesn't matter much. 

Well, the frame is a bit heavy for my liking, but then, you want something that 
is heavy duty, so it probably suits what you want.

As for weight, YES, any extra weight will affect the flight time, but how much 
depends on the build. You will likely get 7 minute flights even with that frame.

Since I am an endurance pilot (I don't do stunts) and my focus is sub-250 gram
craft, every gram counts. I strive to get the most fly time from any of my craft.
On average, all of my quads that are larger than whoops, get between 10 to
15 minutes of fly time and this mostly with 3S batteries. 

With all of this, I would consider a motor with a KV suitable for 4S, run it and
see what you think. If you want to try 6S, then just put a motor limit on it and
try it to see what you think before swapping motors. If you use connectors on 
the motors, one set can easily be swapped for another. This is my standard build 
procedure; I rarely solder the motors directly to the board.

Additionally, I prefer an AIO board over a square stack as they are generally 
lighter, more compact, and generally easier to build with. 


Anyway, that is my 2 cents worth. 

Later, iFly  

For me, i'd probably go 1507 on 4S, probably using the RCinPower Smoox motors. I think both 1804 and 2004 are too big for someone with no real world flight experience.

While 1404 would work, you could go up to 1504 if you want something more middle ground between the two. DarwinFPV make a 1504 that isn't too expensive ($7 per motor). Just remember to buy the 3600kv version, as the 3800kv has a weird mounting size that I don't think is supported by anyone (10x10). If you went with recommended props on that size (GF 3520), you'd be looking at 1.6kg of thrust @ 100% throttle, but it would probably fly ok at 30-40% in a more cruise configuration. Flight times, no idea, but you would probably be able to get at least 8 mins if you feather the throttle on a 650-850 Lipo

For 7-8 minute cruising, I would stick with a light frame and 1404 motors, I don't think you can get more than 6 minutes with the big heavy motors, and if you are not looking for the extra power, or want specifically the feel of a heavy quad, a lighter 3.5" will be extremely more agile and beginner friendly.

Crux35 is a nice cheap, easy to build frame, but has very poor durability. There are alternatives like the Scythe frame or a toothpick style RacerX TwigXL frame among others. Heavier frames will be nice, but not sure you can get the 7-8 minutes (a Crux35 analog or digitial will give your that flight time on a light 3S 450/550 battery).
If you do decide you want something a little heavier, maybe consider the BH1504.5 motors, those perform quite nicely but you won't get the long flight times.

Thanks everyone for your comments.

I've been thinking that in the future I may want a bigger drone, and so if possible would prefer to go 6s. Then the batteries can potentially be used by both drones.

Would these be suitable? T-Motor PACER P1604 Motor - 2850KV. https://www.getfpv.com/t-motor-pacer-p16...800kv.html
They are only 11.6g and should have a bit more power than the 1404, but not crazy.
If they are a good choice, what props would you recommend?

I'm also happy to switch out the grindero frame for something lighter, but don't want something fragile. I'd rather lose 30 seconds of flight time than have something much more likely to break.

Thanks

I have the 4s version on a heavy vx3.5 frame and they perform smoothly. I get 6+ minutes with a 850 4s pack. My 1404 build is more agile, 1504.5 more peppy, but 1604 is a good middle. This is on 4s, no experience with 6s. Depending how large of a large drone you get, sharing batteries may not be ideal as a 5" would probably chew through a smaller pack for a 3.5".

Right now my favorite quad is a 3.5", with an AIO, 1504.5 motors, 4s 850 batteries, barely sub 250g. It flies so well. That is a great size. Realize that if I fly it aggressively I get maybe 4 minutes, but at a leisurely pace approach 7 minutes. With a 3s 1100 and cruising I can fly it 7 minutes plus. So, your throttle stick really determines how long you can fly a nice light quad.
Oh, I have read that if you go 6s you should go with a separate ESC, that AIO's are a bit more fragile.
I have a 6s 5" that I consider my "hot rod" LOL.

Chris Rosser on his AOS 3.5:

https://youtu.be/6EF0rQuiL_U?si=0Czg_yQUBAN51eNB

More power than 1404 does depend on the buildweight.
Recrusionlabs example posted by mtsc does show the peak, there is no more power by bigger motors if you stay low in weight.

For voltage, its not just more is better.
For low weight builds with low current draw, 6s is worse.
When higher cellcount-voltage doesnt give benefits, its allways worse: noise, failrate, weight, costs...

For a 3.5inch build under 300g takeoff weight, 6s doesnt give benefits. I would suggest to choose 4s.

Sadly there are no 5s lipos, they would fill a gap for micros on the edge of possible.

GNB do 5S Lipos, but the 5S ones are hard to find in the 450, 550 and 650 sizes. But they do exist.

https://www.gaoneng.shop/products/gaonen...quare-type
https://www.gaoneng.shop/products/gaonen...quare-type
https://www.gaoneng.shop/products/gaonen...po-battery

(02-May-2024, 02:15 AM)mintjberry Wrote: Hi all,

Looking to get into FPV. I have no other RC gear. I have a heavily modified diy 3d printer and have built dcircuit boards so am very comfortable with soldering.

Have been sim training on Xbox controller while I wait for my RadioMaster Pocket ELRS to arrive.

I would like to build a 3.5' FPV drone. I live in New Zealand, and will probably buy from GetFPV as they have reasonable shipping rates internationally.

I don't think I'll get into racing. Maybe some tricks in the future, but mostly cruising. I live rurally so have wide open areas to explore. That being said I do have a couple of neighbors within around 50 - 100 metres away so don't want anything too loud, hence the 3.5' size.

The budget is around $250 USD. Can go up if really worth it. I want to get a fairly decent setup and not have the itch to upgrade for a while. For now, I think I just want to focus on the drone minus the camera system/googles. Will work that out later, however this is for hobby, I don't need to be mounting a GoPro to it. So the $250 is just for the Frame, Motors, ESC, props etc.

I want a fairly decent flying time, ideally around 7-8mins + when not pushing it hard (which I def won't be at the start).

For the frame, the Grinderino looks decent, though a bit heavy (but durable), will the extra weight limit the flight time a lot? I will purchase some extra arms.
Can anyone recommend decent motors, ESC and props etc? Everything for the drone itself required minus the camera system, batteries and goggles.
I have read that the Aerolite 2004s motors are really nice, but am having trouble deciding on 4s or 6s cell battery, and matching the motor to that size.
Have no idea about recommended props.
For the ESC, I was thinking something like SpeedyBee F405 V4. Is that a good option?

Thanks

Looking to get into FPV. I have no other RC gear.
Would recommend learning to walk before run unless being chased by a tiger. Believe more "learning" could be had with a more forgiving platform = proven formula = lightweight toothpick. Seriously, even with experience under your belt, a toothpick remains fun because they are so light and not prone to destruction when you hit things. You will hit things... even with experience...

I don't think I'll get into racing. Maybe some tricks in the future, but mostly cruising. I live rurally so have wide open areas to explore. That being said I do have a couple of neighbors within around 50 - 100 metres away so don't want anything too loud, hence the 3.5' size.


Again, 3" toothpick or even a light 2.5"er like this:

GEPRC GEP-PT 2.5" Frame Kit
https://www.getfpv.com/geprc-gep-pt-2-5-frame-kit.html

...would serve you well for both learning and future enjoyment. 

It's about managing expectations which gets kerfuzzled from watching utubes with no hands on experience.

The Grinderino with 2004-ish sized motors will scratch an itch that you can't reach right now.

Enjoy the journey, coz it's a really fun ride!...

(03-May-2024, 10:01 AM)Pathfinder075 Wrote: GNB do 5S Lipos, but the 5S ones are hard to find in the 450, 550 and 650 sizes.  But they do exist.

https://www.gaoneng.shop/products/gaonen...quare-type
https://www.gaoneng.shop/products/gaonen...quare-type
https://www.gaoneng.shop/products/gaonen...po-battery

Ya, just saw this:

GAONENG GNB 850MAH 19V 5S HV 120C LIPO BATTERY - XT30
Regular price$20.99
https://pyrodrone.com/collections/gnb-ga...ttery-xt30

...problem for me is the "Karens" who are attracted to shrieking banshee kwardkarpters like mosquitoes to blood.

"Karens" LOL, I have been flying my really small stuff in the park, beautiful place to fly but when I see women (in goggles) I do a 180 and slink away as quietly as I can to another part of the park. Meanwhile all the guys are coming over to me where I'm sitting to ask a million questions while their dogs sniff around
I am in full agreement with skywanderer. If you are just starting out the smaller the better and even BNF whoops are great for learning. But if you decide to fly Digital you may need a fairly substantial quad to carry the FPV equipment.
You said "For now, I think I just want to focus on the drone minus the camera system/googles." Which really stopped me because I think that is the FIRST question that needs to be answered in this hobby. Actual motor specifications for a build is the LAST question that needs to be answered
If you are planning to fly LOS initially I find that almost impossible to do with a small quad beyond about 7m. Since you are on the sim then your focus is FPV and that is a different skill set than LOS.