Derek's New 290mm Quad Custom Build

[Derek]

There is definitely a lot of weight. 5" props just want suit this quad.

As for the voltage after landing, I've honestly never checked. I'll go for 3 minutes or so and land it. Next time, I will fly it and be sure to check voltages after landing.

[Stambo]

I've seen those as well I was thinking of building one for the kids but the other half thinks they are a bit young yet.
so I've got myself all worked up for another build and have seen this http://miniquadfpv.com/product-category/thugframes/
thinking 4s 2000kv'ish

How old are your kids Dan?
My 6yo flies a nano quite happily.
He flies my little V911 helis too.
It won't be too long before I will let him loose with a V949 outside.
Then I will buddy box the Miniquad and let him fly FPV on a screen. (Goggles are too big for him.)

[Derek]

Ok you quad copter pros out there, I've been thinking. I've just been doing some "thinking" not "over-thinking", lol.

My ECHO 290 quad is a boat anchor, weighing in at 862.8 grams. That's with the Mobius cam and a 3S 1550mah 30C pack....basically in it's flyable condition, it weighs that much. That's quite a bit more than any of your quads. I've begun to think that, because of the weight, my motor/esc/prop combination is simply inefficient because I have my timer set for 3.5 minutes and the pack comes down, habitually, around 3.75-3.80 volts per cell. In my flight videos, I'm sure you've heard the LVM beep when I try to give full throttle. I'm thinking that the Sunnysky 2207-2100kv motors just aren't suitable for this quad.

I've built the quad to accept up to 6" props, maybe 6.25". Are there other motors, that are 4S capable and can function well with 6" props, that I can look at for my quad to get a few more minutes of flight time without getting a lot of voltage sag? I don't remember the exact number but Sunnysky makes a 1500kv motor (that would give more torque) but I'm not sure that they would suffice with 6" props.

What are your throughts?

[KevG]

Derek that's quite heavy and you probably have the best motors for the job at the moment, going lower on the kv as I understand it you would need to go up on the props, as they will be spinning slower so less lift/power,

Have you left the carbon sheet for your frame solid or did you cut away lightening holes, maybe that would be an option to lower your weight first,

post up a couple of pics as it is now se we could comment oon how to lower the weight a bit, if you could drop 150g you would prob gain loads from it.

[Derek]

Yes the carbon plates are solid. I understand what you are saying about a lower kv would mean bigger props. Bummer.

I'll post some pics this weekend. I really need to head to bed.

[KevG]

No probs mate, speak soon

[Stambo]

That is definitely a bit heavy for a little quad, what props are you running Derek.
If you can put it on a bit of a diet it will certainly increase your flight time.
Also putting a higher capacity battery will increase it a bit too.
I use 1800 25c batteries on my 250 and they are not enough to give me decent performance.
They were fine when I started but I cannot maintain full throttle for more than a second or 2, I just cannot afford better ones at the moment.
Your 3s 1550 30c battery gives you a maximum amp draw of 46.5. That is 11.6 amps per motor.
However this is calculated with a full battery.
Once you get a bit of sag from running 4 motors off that poor little battery and carrying a portly 862.8 grams I'll almost bet that will be more like 8 or 9 amps before you hit low voltage warning.
You need a higher C or higher capacity battery, or both.
Or maybe a 4s.
Your basic answer is more power or less weight.
The motors are capable if you supply them enough amps and the right props.
Perhaps try 6045 props if you have not already and monitor the motor and ESC temps.
Basically though I think you need better batteries.

[Graham Lawrie]

Its a hard balance to get when trying to keep the weight down:)

[Derek]

After a bit of thought and tinkering....my crashed ECHO 290 quad will be reborn. It's going on a diet to shed some grams.

More to come..

[danhampson]

Is this the machine we spoke about on Skype Derek?

Your secrets safe with me.

[Derek]

No, this is a lighter version of my previous echo 290 fpv quad. I crashed it many months ago and I just put it on my workbench in the back corner. Then I decided that I was gonna move away from quads for a bit. Then... You guys keep posting your quad experiences and I got thinking. I decided to try that custom project that I was talking to you about and build a new 250 quad. I've been drawing up dimensions for the big quad and I got the 250 quad done. However, there are a few parts of the 250 quad that I seriously don't like. So... I've decided to strip down my previous echo 290 FPV quad, to bare bones, and remove some of "this" and a little of "that". I'm confident that the reborn ECHO 290 quad will be lighter than the original build.

More to come and I have been taking pics to display progress.

[KevG]

nice Derek, looking forward to see the Mk 2 version

[Derek]

Curious question...how are you guys mounting your GoPro's to the nose of your quads? I have a front ledge on my quad that an ActionCam can sit there but it would have to sit there without the protective case. If the protective case were to be used, I wouldn't be able to get the camera in nor out of case. So, I'm wondering, are you guys just using a Velcro strap or something similar to hold the ActionCam in place?

[Graham Lawrie]

Havent seen anyone use the case Derek:) but have seen a few broken Gopros:)

Its quite easy to use the mount as normal, but wedge the front up slightly, then just velcro strap it

[Derek]

OK Graham. Thanks! I'll see what I can come up with. I should be able to post some pics of the "reborn" ECHO 290 quad this weekend.

[danhampson]

ive been using high density foam and some thick zip ties. It works for me, i have had velcro straps let go on a couple of crashes and spent quite a while looking for the camera that was thrown quite a distance from the quad.

[Derek]

That sounds like a good way to go, Dan. Thanks for that.