It looks like this will be one of the easiest builds for me to date. The main reason is it is all plug and play... The only soldering I should have to do is the XT30 power connector.

Here is the list of parts.

Frame - URUAV UR85/UR85HD 85mm - 8.5g
Flight Controller - Happymodel X12 5-in-1 F4 12A ELRS w/400mW VTX - 5.1g
Motors - RCINPOWER 1003 10000kv - 3.45g ea
Props - HQ Prop Durable T2x2x3 Tri-Blade 2" - .75g ea
Camera - Caddx Baby Ratel 2 Nano - 3g
Canopy - HappyModel Crux3 - 1.2g
VTX Antenna - HGLRC Mini Hammer 5.8GHz U.FL Antenna RHCP - 2g
Battery Connector - XT30

Weight - 41.23 grams
Weight with 2S 450mAh battery - 67.18 grams

                                                    

One of the things I really like about this frame is that the duct strut that goes to the FC has a channel in it that you can press the motor wires into which keeps it nice and clean...

Those are 1003 and not 1103 motors? Looks like it will be a light agile flyer. Are you planning rubber bands for the battery? The Mobula8 and Meteor 85 frames have a larger battery bay for 2S packs so that might be an option.

Edit: Meteor85 frame only has 4 hole motor mounts

(01-Dec-2023, 12:22 AM)mstc Wrote: Those are 1003 and not 1103 motors? Looks like it will be a light agile flyer. Are you planning rubber bands for the battery? The Mobula8 and Meteor 85 frames have a larger battery bay for 2S packs so that might be an option.

Looks like I made an error in my listing (fixed)....
They are 1003 motors...

These motors will work with either 3 or 4 bolt mount options. I wish more of the smaller motors came like this.
This frame fits a 2S 450mAh battery perfectly.

Those props in the 2" and 2.5" are my current favourite, go to props. Not to aggressive, but still give a lot of lift. They also take a licking and keep on. i have managed to bend them a few times and they are a real pain to bend back, but they will and it will still generally fly ok afterwards.

We got to talk.
How did you get the weight so low!

I have same RCinPower 1003 but 2023 props. I used 4.5g light JHEMCU Rubit F4 12A FC. Its Cub 88mm frame.

(01-Dec-2023, 06:58 AM)romangpro Wrote: We got to talk.
How did you get the weight so low!

I have same RCinPower 1003 but 2023 props. I used 4.5g light JHEMCU Rubit F4 12A FC. Its Cub 88mm frame.

I updated the original post of the parts list to include the weight (as listed by the manufacturers). 

My FC is actually heavier than yours...

I just looked up your frame, and it's listed at 14 grams. That's 5.5 grams heavier there.

EDIT:
I just looked up your FC and it looks like you are using an external VTX. The FC in this build has both RX and VTX built in. Depending on the VTX you are using, that may be another weight gain area...

Mine building a whoop on a Mobula 8 frame. FC Happymodel Crazy F405 HD AIO ELRS. Motors HGLRC 1003 kv10000. EMAX Avan blur 2" props. I'm waiting for Avatar 1S Lite to arrive. Already flown in LOS mode.

AFAIK, based on flying 2" 1003, 2.5" 1202.5 and 2.5" 1203..
by far the 2.5" HM1203 is the most fun. Feels MUCH more responsive.

Sonebody did HUGE comparison of 20+ micro motors, and pretty much same conclusion. HM1203 is great.

Ok, I got a new problem here. I got the binding figured out in another thread, but now when I arm the quad two of the motors spin fine and two of them spin a bit, stop, spin a bit again, stop  and keep repeating. If I give it some throttle, it will take off and I have hovered for a few moments, but land right away in case there is a problem, I do not want to burn anything out.

I have a slightly older version of the FC in an identical quad except the other one has 1102 10000kv motors where this one has 1003 10000kv motors. I have tried to use the settings from the older quad but I see that the newer FC has a different gyro and that seems to change things. The older FC has a gyro update frequency of 3.20 kHz with the pid loop at 1.60kHz. The new one has a different gyro as it is a 8 kHz update frequency so the pid loop should be 4 kHz? That is where it is set now but I still have the issue.

The other thing I noticed that was different between the two was the older FC in Blheli has a startup power of 0.50 where the new FC was set at 1.0. I have no idea what that does, just noticed that it was different. I have tried 0.5, 1.0, and 1.5 with the same result.

Both FC's have Bluejay on them at 48kHz with bi-directional dshot set at 300.

I am guessing that the different gyro is what is causing the problem trying to use the same settings as the older FC.

Can anyone clue me in on what I am missing?

It's possible that you have an issue with the ESC's or the motors. Raising the idle speed usually fixes the problem, but if you raise it too high you will end up with a floaty quad that won't descend very quickly when you drop the throttle to zero.

If you spin the motors up in the Motors tab of Betaflight Configurator using the single slider to spin all 4 motors, do they behave the same way with 2 of them stopping and starting? Doing that will eliminate the PID controller because it's not active when spinning motors using those sliders.

If its the 42688 gyro, I've seen a lot of threads about it being really shakey and needing very clean power, although how you get that is anyone's guess. You could run a big cap to try and remove the ripples, or maybe two smaller caps in parallel. Seems like most of the TDK gyros seems to have some issue with power. My 20689 did and adding a 330uf cap solved probably 80-90% of the gyro quirks, but not all.

If it's the BMI270, I don't know. I know there are some settings that need applying to the config. I have one, but it's not operational yet.

There was recent thread concerning your FC and the gyro issue. Hopefully you find a solution.

(16-Dec-2023, 01:35 PM)SnowLeopardFPV Wrote: It's possible that you have an issue with the ESC's or the motors. Raising the idle speed usually fixes the problem, but if you raise it too high you will end up with a floaty quad that won't descend very quickly when you drop the throttle to zero.

If you spin the motors up in the Motors tab of Betaflight Configurator using the single slider to spin all 4 motors, do they behave the same way with 2 of them stopping and starting? Doing that will eliminate the PID controller because it's not active when spinning motors using those sliders.

Just spun the motors up in betaflight and all motors are fine...

That pretty much proves that the motors and ESCs are fine then. So it might be something to do with the gyro. Run the "status" command in the CLI and it will tell you what gyro you have. IF it's one of the ICM gyros then as Pathfinder already mentioned, it's a known fact that gyro can be problematic which is why a lot of people steer clear of them.

You can check to see how if there is any excessive gyro noise by placing the quad on a surface that has no known vibrations running through it so that it's perfectly still, then connect the FC to Betaflight Configurator and go to the Sensors tab. Untick everything at the top except the "Gyrocope" and "Accelerometer" and check the graph to see how close to flatlining it is, or isn't. The default scale for the gyro is 100 but you can reduce that to a lower value to see more sensitivity. If you see lots of random erratic spikes then you could have a problem with the gyro, or a filtering issue with it.

I ran the status and it has the ICM42688P gyro. The other one just like it that I was trying to use the settings from has a BMI270 gyro in it.

I searched the forum for the ICM42688P gyro and can't find any posts that have any info on how to tune it. I don't know anything about tuning or filters so I am not sure what to try next...

Here is a pic of the noise with the scale set to 10.

   

Just for comparison sake, here is the same test using the BMI270 gyro and it has more noise and the motors spin fine.

   

Well Googling the problem I found the thread here that may help, but I don't really understand most of what they are talking about.

https://intofpv.com/t-hakrc-f722d-40a-aio-gyro-issue