finally i can begin my first attempt at melting lead on a 5in lightweight build. its based on the alfarc grasshopper 5in LR frame. i shall not drop names but it looks like a child out of wedlock from some very popular celebrities in the fpv community. frame is quickly assembled for completeness and proper fitting. fortunately everything checked out and the arms are wobble free despite the usual DC format. i may sandwich a layer of thin double sided tape between the arms and frame plates for good measure in the final build. it weighs 66 grams using only the tpu prints for vtx antenna and gps module platform.



photo below shows the other components to complete the build. only thing missing is the happymodel EP1 dual diversity receiver.

Nice looking frame

Glad to see you're starting 
And nice frame, I think I've seen it before...  

yes i finally took the plunge into DIY! the bnf options are beginning to cost dearly and have limited choices for my use case preference(s).

BTW i plan to flash the ESC with Bluejay via web based ESC configurator. is it safe to flash the latest and greatest firmware? would hate to brick a new build!

No, only put 0.19.2 on. 0.20.0 kills motors and ESC's. There is a note on the esc-configurator front page about it.

Hi Hawk,

I have a philosophy of NOT updating any firmware until the build 
is complete and the quad is flown with all defaults; both firmware 
and configuration. Until the craft is flown, one has no baseline for 
its behavior.

1) Build,   
2)  Fly,   
3) Only configure as needed,  
4) Only update if absolutely necessary.

From my perspective, it does not make sense to update or even
tune something without knowing the craft's initial flight characteristics
and behavior.

Later, iFly  

yes!

i shall fly on stock BF firmware and see where it goes. since the board is relatively new, it should at least come with BF4.3.X which already have adequate features for gps rescue, etc.

the build encountered a slight delay. i had to decide in favor of a suitable motor with M5 prop mounting in favor of Tmount. i got BH VY1507 1550kv replacements coming soon. these have a bigger motor volume compared to the Emax Eco2 2004 1600kv it replaces. although both weigh almost identical. would there be any benefit to the larger motor volume?

https://www.brotherhobbystore.com/products/vy-1507

i call it a myth, there are many swear about more efficiency on more wide stator.
i believe in a bit of difference about inertia and therefor i like high stator.
the motor volume priority and hight and wideness gain less attantion when i choose.

as an example against the actual trend for more wide motors in fpv foe efficiency, dji arial video drones with their endurance does use hgh staors.

(do you plan to fly it on liion battery? if yes i would choose a higher kv motor. there is lower average voltage with liion and they can be flown to lower voltage.
i would choose at least 1800kv for the use on a liion 6s, i would maby choose 2800kv and scale it down to the max rpms matches well.
a 300g 6s liion might be to heavy for suchs small motors anyway to stay in an efficiency level.)

oh i see!

i plan to fly it on both li-ion and lipo at the same time. now i have 6S 18650 for use with this quad. will see how it goes… if this pack proves too heavy then i could split it and make two 4S 18650 packs. just buy another two cells extra to make another 4S.

For tall vs wide, I have heard that taller motors are actually more efficient at higher speeds and also yields more surface area for the magnets. But the problem is tall motors tend to have poor cooling, and when motors heat up they will lose both power and efficiency.

In terms of larger stator volume, you will get more torque/power in flight, but also consume more battery, but it will depend on the motors. And 2004s actually have slightly more stator volume than 1507s.

given the 1550kv running on 6S hopefully in the mid-throttle region this thing will not be having overheat issues.

Hi Hawk,

I agree with Mstc. 

Well, the 2004 motors have 1256.56 stator volume compared to the 
1507's 1236.93, however, that is an insignificant difference.

Although I have not tried to do this comparison, the thinner/taller motors 
are said to have more acceleration and top end while the short/wide motors 
have better cooling due to a larger "air" intake area and tend to be better 
on the low end side. However, there might actually not be any noticeable 
difference for an endurance quad. 

You know, I have not heard of an endurance pilot having heat issues. Plus, 
I have done all sorts of "over" propping with no issues. Even the 1103's 
spinning 4-inch props did not heat up. By conventional wisdom, they should
have, but did not. It would be really hard to say, one way or the other, but
cruising at half throttle or less will likely not stress the motors.

Now, let's think about this. A motor does not normally heat up when running
within the operational parameters. Motors heat up under the stress of loading
close to or beyond their normal running capacity; things like extra heavy 
payloads or a heavy throttle. Plus, some folks "tweak" things to get a bit more 
performance which might push a motor beyond normal operating parameters. 
Most endurance craft likely don't tend to have hot motors as the craft are flown 
well within the operational parameters of the motors. If anything, my "over" 
propping should produce hot motors, but, so far, has not. Hmm. 

So, you will have both motors, right? You might consider using one set,
use different batteries, maybe even different flying styles, log the data, 
check the motors for heat; then try the other ones and compare the 
data. If neither motor gets hot (my money says they will not), then
you could use the ones that get the best Fly Time. 

Since I use motor plugs, swapping motors would be a relatively easy
thing for me to do without the need to solder anything; plug and play.

Even though both motors are smaller than the hi-performance folks
would consider, I will bet that either one will be fine. Although the 
300 gram battery might be a little bit heavy, I would give it try
anyway since you have it. Just start with small, short, close, flights
and check the motors. As long as the motors don't get hot, then it
should be fine. Well, I probably would not try fancy stunts with it.

Edit: I forgot about the T-Mount vs 5mm concerns; 
       so maybe stick with the 1507s with the 5mm 
       prop mounting.

Later, iFly  



 

I have noticed on several vendor sites, that they are beginning to sell stacks
with MR30 connector pigtails and the battery leads already soldered to the 
ESC board. 

Such as shown below on what looks like a SpeedyBee stack:


I have these MR30s on my Rescue Quad build. Now, I am thinking about using them 
instead of the servo connectors for more of my builds. Yes sir, these are heavier than
the servo connectors, however, likely have less "resistance". 

As those who follow me know, I use connectors for almost everything including the
motors. They sure make swapping out motors a whole lot easier and simpler. 

Now, if a digital system is used and just plugs into the FC board, then the burden of 
soldering is greatly reduced. Plus, soldering connectors on the motor pigtails is likely 
ess stressful than soldering tiny pads for those new to soldering. 

excellent way to ease the newbie into the hobby. as we discussed before, this is so convenient for those times when you want to migrate gear over several quads. for an HD system this translates to significant cost savings by moving vtx and all among several quads.