Hi all,

I'm Kevin from the Netherlands, I live near Amsterdam and have been building and flying multirotors for around 2,5 years now.

Recently I finished my Shendrone Corgi build, it was not an easy build and I have redone it 2 times before I was happy. Now I'm in the process of tuning it (PIDS) and I feel it's too heavy.

With the gopro and Lipo it weighs 680 grams and I'm looking to shed some weight. The copter consists of the following components:

• Kiss FC: 5 gram
  
• 4 x Kiss ESC: 3.6 gram
  
• Shendrones Corgi 147 gram
  
• 4 x Cobra 2206 2400kv V2 32 gram
  
• gopro here session 4: 74 gram
  
• Sony HS1177: 12 gram
  
• FrSky naked X4R-SB LBT: 5.8g
  
• ImmersionRC TRAMP HV: 4g
  
• TBS TRIUMPH antenna: 10 gram
  
• Tattu 1550 gram Lipo 180 gram
  
• right-angle sma connector 3,5 gram
  
• propellors 4 x 5.9 23,6 gram
  
• polulu 5 volt 
  
• buzzer
  
• pdb 3,2 gram
  
• 2 x matek RGB leds
  
• wires, some hotglue etc
  

I know it's not the lightest frame out there, but I like because it's the only frame that you can insert a gopro session in, it's basically a tank .

Some notes: the reason I have a 1550 lipo is because the 1300 was not handling the cobra's very well, and I really like the power. I use the copter for freestyle.

I'm open for any suggestions .



Kevin

Welcome to the forum, nice looking quad. You could reduce a little weight by going to a 1300 mah lipo. It's not the mah rating that gives you power it's the C rating. What's the C rating on the Tattu you're currently using?

Hi Kevin and welcome to the forum!

There's not really any weight to lose there if you want to keep those motors. As you say, they are a bit thirsty to go down in battery size, but you like the power.

As the old saying goes, there ain't no such thing as a free lunch!

Hi,

Thanks for the feedback, I know it's the C rating that gives power but 65C on a 1550 gives more power than 65C on a 1300 .

Anyway, the tattu is rated at 75 C, while that MRP 1300 I have are rated at 65C.

The reason I feel it's too heavy, is that sometimes the quad flips over when trying to do some acro manoeuvres. But maybe I can fix that by some more tuning.

The reason for this post was that I saw someone else building the corgi with AUW of 619 grams (using the same lipo):

https://fpv-flightclub.com/shendrones-co...er-review/

I do have a polulu and leds on it. And I'm using some more wires on the esc's, but those don't weigh 60 grams..

Kevin

I'm not sure I believe that 619g weight. Sure, there's 4 x 4g saved with the lighter motors and as there are no props shown in any of the pictures, then maybe that weight doesn't include props. Even so, I can't see more than 40g difference.

You say it 'flips over'? I'm not quite sure what you mean there, but the only thing I find if a quad is heavy is that it's not as nimble in the air and can't turn or change direction as quickly as a lighter quad.

That frame is a tank and surely weights like one. But you want to stay with it. OK.

Calculating what is inside, going trough the points down to the props, we are at just under 600grams where pololu, buzzer, PDB, LEDs give you maybe 10 grams.
The rest of your weight is all the miscellaneous items like wires, glue, fasteners, heatshrink, insulation tape - this is the things that you can look into.

What I would get "rid of" is the antenna. Sure it is an exceptional piece of equipment, but in all seriousness thats heavy as hell and you probably also use the Tramps pigtail. Go on and get a linear antenna with ipex plug. You can even go as far as making your own 5.8mhz Vee antenna out of it - my Vees weight 0.5 gram and give me enough range to freestyle freely. 
If you want to go that route, those are great to work on: http://www.banggood.com/10X-150mm-2_4G-R...mds=search

Vee antenna is a veeeeery simple design:


Where red part is the insulated "active" wire and black one is (im my case) usually a soldered on piece of 28AWG wire. From what I've heard, design A is the most effective - also the only one I've tested

Thats 12g for the antenna + about 5-7g off on the pigtail. You are 17-19 grams off

What lipo wires are you using? Use the shortest lipo wire possible - keep it just as long as needed to conveniently plug the lipo in. On one of the builds I've saved 10g just by shortening that FAT wire. Also - if you followed AWG wire charts you've made it... too fat. Realistically a 14-16AWG wire is all you'll ever need. I'd go 14 in this case.

You are comparing your build to another one - keep in ming that he's using lighter motors - that's 16g difference.

We are already at 43-45g difference, so 680-45? ~635g AUW.

Other things to look at:

• what AWG size did you use on ESCs? I know that KISS don't come with any wire and you just use what you pick. I'd probably use 18-20AWG here.
  
• You didn't show us how you wired your FC - is it directly soldered (probably yes due to the frame used)? You will save a lot of space and some weight by not using pins and plugs.
  
• are you using aluminium or steel hardware? Using aluminum may give you some serious savings.
  
• take a look on how much heatshrink, insulation tape and zip-ties you use - those things add up.
  

You could save more than 12g by using lighter props, and you might like the faster response

But if you say it flips over, that sounds more like a de-sync where you would have to increase minimum throttle. Lighter props could help here too though.

I was going to say smaller gauge wires and aluminum or titanium hardware if steel is being used, but KonradS said things way better than I would have

Good lookin' quad though! Even if she is a big girl

Hi, thanks all! Will definately look into the antenna hack from Konrad! I already have those antenna's (spare rx antenna's ).

I'll take it apart and show some pictures of the insides later, will definitely look into shortening wires and use thinner wires when possible.

Standoffs are aluminium and everything is direct solder, except for the vtx, camera and the telemetry wire from the rx.

It looks like the prop change is already saving some weight! The red ones are Dal cyclones vs the green HQ 5040 triblades


The belly of the beast, the lipo wires do look bulky.


I decided to remove both the ground and telemetry wires from the esc, not sure if I'll be able to update the esc's without the telemetry wire but it's an easy solder if this is a requirement.

Anyway, my solder iron is heated so I'll get on with it. More pics when I'm done (hopefully it will still work afterwards).

12 AWG lipo wire with xt60 connector vs 16 AWG, 4 grams off.


Removed signal wires, 2 grams off.

Rewiring done, 18 awg vs 20 awg esc wires is about 1 gram off. I went as far as using a solder sucker to remove all exces solder, also done some better wire routing. Looks way cleaner now.


Next up, putting her back together again and see some results . Still pondering about the motors, I actually do have some emax redbottoms. But the cobra's run so much quieter/smoother and are more powerful..

So, what did I accomplish. I managed to shed off 16 grams by changing props and going back in wire thickness, not bad! This is without sacrificing much performance (only HQ props VS dal cyclones).

I'll be ordering a linear antenna, and still thinking about the motors. The redbottoms weigh 30 grams vs the 32 grams of the cobra's, that's 8 grams. Changing the antenna and removing the tramp pigtail will save me another 17 grams maybe? So then I'll be down to 640 grams. I'll just try it and see how it flies .

Thanks for all the suggestions.

Brotherhobby r3 or r4 is 28 gram each

I can't tell exactly where the power wires go here:



But it looks like you switched polarity here...



I just hope my interpretation is wrong...

PS: For a future build, there's a miniature version of the kiss24a coming.

PPS: On my latest builds i used simple cord and glue to replace any zip-ties (instant adhesive instead of knots, very easy to do, and so far lasts longer than zip-ties which break sooner or later). I don^t see any zip-ties on your build, so this is just a tip for anyone else reading through here.

Hi fftunes, nice find! But fortunately I have polarity right, I just used other pads for the lipo leads . I used the multimeter to verify this again.

Really looking forward to the mini kiss esc24a . Right now I don't think a motor swap to the emax will help much. I will probably sell my cobra's and buy lumenier 2206 2350's, that will save me another 20 grams and they have less amp draw so I can away with using 1300 mah lipo's (another weight saver ).

Anyway, right now I installed the linear antenna and I'm down to 644 grams . Really curious on how the linear antenna performs, hopefully my attitude v2's with the FS diversity RX mod will somewhat counter the loss of gain from the linear antenna.