Derek's ZMR250 Build

[Derek]

Well, I imagine that moving the bec forward will only help me because I'm sure it was slightly tail heavy. I'll put the ZMR into Horizon Mode and I'll play with those adjustments.

Besides that, the hover test was great! It was not hard to control at all. It was awesome to hear the smoothness of the props...as if the entire system was speaking to itself in the same language. Give hard throttle and all 4 props would zing...all at the same time. I'm gonna get a few batteries charged up and head to the field for a bit today. I have a wedding to go to this afternoon but I should be able to fly a bit before hand.

[Graham Lawrie]

Betaflight is the way to go Derek and Luxfloat:)

[Derek]

I don't remember what version, but I am running Betaflight. In Cleanflight, I know that I have it set for the Re-write...I think. I may mess with the Luxfloat. I'm just happy that the darn thing flies, lmao

[Graham Lawrie]

If you go to CLI and type "DUMP" and scroll to the top of the page you will see what version you are running:)

[Derek]

lol...I didn't know that, Graham! Thanks for that! I'll do that and check.

[Derek]

Oh WOW! I was just outside running my 250 around my yard a bit....LOS. This thing is so so super smooth and predictable. The roll and pitch may be a bit more sensitive than I prefer (I haven't decided yet, lol) but it definitely jumps around quite quickly and very agile. Hearing the smoothness of the hum of the props, in synch, is just amazing. I'm actually quite happy with the "punch" that the quad seems to have with my 3S 1550mah pack. I do have a 4S 1400mah pack but I've not even taken it out of the box yet. I'm running 5x4 props right now. I think they are HQ props but they are definitely hopping the 250 around with ease. I may just leave my 6x4 props (about 30 of them, lol) in my "spare props box" for the time being.

[DOG]

Sounds like you finally got it together and your happy with it. Maybe now you can enjoy flying it for awhile. Good luck with future flights!

[Derek]

Thanks Dog! Yeah, it's definitely behaving very well. I'm hoping for some FPV next week.

[Stambo]

Good to hear Derek.
It's not difficult to tame it down in the naze32, if you post up some screenshots of your settings we can soon tell you what to adjust.
Look for roll and pitch rate and drop them a little, on the same page as PIDs if I remember correctly.

As far as I am concerned the HQ props are the best.
I have tried Dal and Gemfan and although they are a lot less likely to break when you hit something, they don't seem to feel as good.
And if you hit something and bend them, you still have to replace a prop because they vibrate so much.

Save that 4s pack until you are real comfortable FPVing it.
Once you run it, the 3s will never be good enough.

[Derek]

Thanks Stambo! Yeah man...I'm stoked that the quad is flying as well as it is. It's just awesome to be quad-flying again. It's something that I can play around with in my own yard (within safe and realistic limits, of course). I'll get a screen shot posted soon.

I've got some GemFam props but the HQ props just feel better in my hands. Because I do have the GemFams, I will surely use them. No sense in letting them just sit around. Then I'll get on to the HQ props.

As for your suggestion on saving the 4S pack....that makes sense and I rarely argue with something that makes sense, lol.

Let me ask you this though...I have many many 5x4 props and many 6x4 props. Now, my ZMR is seemingly flying very well with the 5x4's. Will I ever be able to use the 6x4 props or should I just sell them off?

[Stambo]

The 6x4s will probably give more top speed and a longer flight time at the expense of a bit of punch and crispness.
A bit like the difference between 4th and 5th gear in a manual gearbox.
In theory they should be better for smooth gentle flight however I found they needed to be balanced where a 5x4 you can get away without it.
They should be better for scenic video with rates dialed back but I haven't tried it yet, I have some as well which may end up on Jacobs quad.

[Derek]

ok, I understand all that. Let me ask you this...

You pretty much know my ZMR setup. If not, here is a reminder:

SunnySky 2217-2100kv motors
Little Bee 20amp esc's

Would I be ok to use the 6x4 HQ's without burning up the motors and esc's? Or, let me ask this....how can I test this? I do have a watt meter that I can use. It just scares me a bit (ok, quite a bit) to be anywhere near the quad while running the props at full throttle on the bench. It really concerns me because....picture this....

...strapping the quad to my work bench would be easy enough....I know I can secure it. Add the watt meter....power up everything...point my video camera at the display on the watt meter (because I won't be anywhere near it)....and it just concerns me that a prop, or props, could break during the test. Who knows what direction the prop bits would go?

What kinds of thoughts can you share here?

[Stambo]

I would just fly it for a minute, bring it down and test the motor temp.
Fly it for another minute and test again etc.
I have the same motors and props and with 5x4 they hardly get warm.

As for bench testing, you should not need full throttle for very long, I would only test between half and 3/4 for any sustained period.
If you think about it, how often do you fly a quad at full throttle for any length of time.

I just checked the specs and with 6040 on 3s max current is around 15 amps.
Thrust is around 560 grams at 165 watts and temp is only 41 deg.

[Derek]

Sounds good

[KevG]

Derek I'm running dal 6045 bn on my gravity 280 with cobra 2206 2100kv and little bee 20a and have not had any issues, it's not like your gonna be flying it like you stole it are you

[Derek]

Lol...I don't fly anything "like I stole it" lol

[Derek]

I also discovered something at yesterday's FPV Event. I have mentioned, in this thread, a few times that I am running 5x4 props on my ZMR250. That's not the case at all, lol. When one of my props came off yesterday and I had to search my stuff for a replacement...I found that I have been flying 5x3 props. I still have some 5x3 props left over from a previous build and apparently I put them on the ZMR and didn't realize it. Funny!

[Stambo]

You will be amazed at how much better the 5x4s will be, especially on those 2100kv motors.
I recommend 5x3 as a starter prop, I still have some left from when I got started.
I am sure Jacob will use them up though.

[Derek]

I have no problem running the 5x3 props right now. As you could see from yesterday's video, the ZMR seems to do real well with the 5x3's. I'm happy with it. Once I tear up the rest of my 5x3 props (two more full sets), I'll get into the 5x4's and 5x4.5's that I have.

[Derek]

Two days from when I ordered....I check my mailbox expecting junkmail.....no junkmail but these arrived.....VERY COOL!!!

20160721_215609.jpg (83.92 KiB) Viewed 4319 times

No, they aren't Pulse nor Tattu packs, but for me....these will give me more stick time. My other 3S 1550 packs are 30C....these are 45C, so there has to be some improvement.