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Mar 25, 2018, 06:36 PM
Registered User
Data

Multirotors 4008q and 3508q, charts, methods, wind n power system planning

Hi, finally got something up here as blog
First blog and will add and edit, like a living document, please don't be offended if I delete something, will try to keep this short and neat like a manual

Fun flier 3 cell 12v power using LIFE batteries, thrust for fav 3508q and similar is 2 to 3 pounds
Here the first chart 3508q planned for wind either using 12x8 bush plane, 10x7 faster warbird, or 8x6 for a quiet prop jet

The charts say it all too, text cannot be shifted in a pic! See how you like this idea, the chart is for HPdLRK wye only, 2x wire current spec

Easy way to figure new turns for a new kv using old wind of same type, you can also use turn calculator, and see on the bottom of wind diagram, how each wind type relates by what multiples or numbers

An earlier wind HPdLRK wye 14 turns 1105 kv
14 x 1105 = 15470 product
divide product by desired kv and see what's close and divide by turns to zero in on predicted kv from turns
15470 product / 22 turns = 703 kv

motor wound w 22awg hpdlrk wye good for 256 watts or a bit over 3 pounds thrust (10.668amps x 2 = 21.336tot amps x 12v = 256 watts)

The low kv winds will likely need 22awg, stuffed it full on 26.5 turns and missed 5 turns on a 586 wind, so we can guess about increasing size as turns decrease

I really like the diagram system I use, think about it, circled numbers are counter clockwise

https://www.rcgroups.com/forums/show...-parallel-dLRK

Third a chart on flight test FT Mustang scaled up with wire charts etc

Now here's why I keep on trying to get the most thrust for the least amount of power, my 12v LIFE packs only come in limited capacity, but when tested with 586kv motor and gws 12x8, ran wot for 10 minutes continuous pulling about 10 amps!!! That's 2 pounds of thrust for 10 minutes load about 110 watts

Next time I wind one of these, 22 turns 22 awg 703kv est 3# thrust 50mph apc e 12x8 from flybrushless thrust calc, definitely using the adjacent coil wind, yes!

Leonard

Images

Last edited by leonard3k; Apr 24, 2018 at 01:03 PM.
Mar 26, 2018, 05:37 AM
Registered User

how much power for how much thrust, etc

I still like referring back to this gws 9x5 thrust chart, now even more

With a rewound motor at low 600 to 700kv and a 12x8 prop, 2# thrust takes 110 watts, 3# 209 watts

Look at this 9x5 prop/thrust chart... appears to take just a little more power for the same thrust, see the motor that was tested too

Am I doing any good, or is this persuit of more thrust for less power trivial?
I get 3# for 210 watts with a 728kv hextronic d4023 and a gws 12x8 dd at 6.48 g/w
Cobra 3520 -- 820 kv 12x8 apc e gets 52oz thrust for 332.3 watts 4.46 g/w
that's an almost even comparison, but with a 12x6 they get 57oz 266 watts 6.13 g/w

So I get 3# for 100 watts cheaper than commercial deltas, but, that extra kv you don't need, cost more in watts!

change in pwr expected on the above ft mustang chart, (820kv/728kv)^3= 1.429
1.429 x 210 watts = 300 watts for higher kv

If I plan on using 12v and 12x8 props for 3# then 703 kv is all I need and all over 703kv is wastefull

The larger stator motors give 3# thrust at lower kv, the scorpion 3020 at 624.6kv LRKy 0.84nls!!! nice numbers for 45.43oz see below pic

Leonard

Images

Last edited by leonard3k; Mar 28, 2018 at 05:36 PM.
Apr 11, 2018, 11:34 PM
Registered User
I've been wanting to make a better looking wind of the iFlight 3508q, the last effort for more thrust-less power was wound with half turns and 5 missing turns. No more half turns, those bird nests on top look bad and prevent heat dissipation.

The limit how much wire can fit was reached 27 in slot of 22awg doubled is 54 x 22awg area...
54 x 0.326907397215mm^2= 17.653mm^3 (26.5t)
52 ....... = 17mm^3 (26t)

The simplicity of the dLRK wye wind is beautiful, after some guesswork
13t 20awg for 595kv (26 in slot 13.5mm^3) 13.653a (75cm/a) x 12v = 164w about 41 oz thrust
13t 19awg for 595kv (26 in slot 16.9mm^2) 17.184a(75cm/a) x 12v = 206w about 48 oz thrust

595kv with 12v would yield 40oz thrust w 12x8 prop, so that would be the limit, the motor would
probably only use 150 watts or less, been wanting to try another that gives 32oz thrust on low power

I have some more 3508q motors ordered from iFlight and just got some green wire, hope to maybe wind
some with two colors, hp dlrk wye adj coil wind

You may really like this new AWG wire chart I made up with Luciens pdf

Leonard

Images

Last edited by leonard3k; Apr 24, 2018 at 01:05 PM.
Apr 21, 2018, 10:08 AM
Registered User

Lowest powered 3s motor wind for 2# thrust

I wanted to experiment at the lowest kv that would still give at least 32oz thrust with either APC or GWS 12x8 props.

The last 3508 wound for efficiency g/w thrust Io = 0.65 amps, was 26.5t with about 5 missed turns

28t 23awg HP dLRK y for 553kv at first estimating .82nls (I like this term Manuel V shared)

Wound n tested Io looked so good at 0.4 amps, so I'm using and guessing wot load estimation of 0.84nls instead of 0.82

7260rpm/13.10 volts = 554.2kv 13.6a(75cm) - 17a(60cm) --- 163w - 204w 60 inches of wire p-p = 0.10151ohms

0.84nls x 12v x 554.2kv = 5586rpm 12x8 props 42mph
APCe 951g 33.5oz
GWShd 999g 35.2oz

APCsf 5k 42oz 38mph

prop adapters in order coming from iFlight

Leonard

Images

Last edited by leonard3k; Apr 24, 2018 at 01:05 PM.
Apr 22, 2018, 01:00 PM
Registered User

Low KV motor poor wire fill runs hot... running too close to wire's current limit

This idea was a flop, might have worked with an odd size between 23 and 22awg, this one was just too close to the limits of the wire

Just tested at 5340 rpm (2# thrust) gws 12x8 ep 12.38v 9.3amps 115.134watts and runs hot

APC 10x6 ...6300rpm 12.6v 6.2a 78.12w 23.12oz 36mph 655.4g 8.39g/w

I would have made a much better motor with 23 or 24t of 22awg like I was planning above

This one should be easy to strip, didn't put too much epoxy on wires

I'm going to check wot nls figure and add here later

Leonard

Images

Last edited by leonard3k; Apr 22, 2018 at 02:38 PM.
Apr 24, 2018, 08:50 AM
Registered User

Problem with 28t 23awg motor solved

It's not poor wire fill, I kept on thinking about this; I used the 75cm/a rating and it ran hot ------ So it's best to use the standard 100 cm/a rating or plan your wind and motor load around the 100 cm/a ratings for cool running motors

All my 2# thrust tests run 12v with 12x8 props and use about 9 to 10 amps, this motor tested at 12.38v 9.3amps ran hot, so I think using the 75cm/a rating is a bad idea

Wire fill? No. This 23awg motor was 99.3g AND the new motor I just wound same way with 22awg IS 101.3g --- Same wire fill --- Same motor gram weight.... What was different, the wire capacity, not the gram weight capacity(100g x 3w = 300w)

22awg 100cma = 7a hpy 14a ......... 75cma 8.53a hpy17a limit ---- cool running to 168w or about 43oz thrust 14a hpy 100cma

23awg 100cma = 4.7a hpy 9.4a ..... 75cma 6.81a hpy13.6a limit ---- runs hot just at 115 watts 32oz thrust

hpy = half parallel wye

Best to use wire charts for 100 cm/a for better cooler running motors

Leonard

Images

Last edited by leonard3k; Apr 24, 2018 at 01:07 PM.
Jul 20, 2020, 04:30 PM
Registered User

Best improved HPdLRK wind yet get more wire on stator

Hi, this gets the most wire on the stator winding HP 12n14p or any similar, wind first coil the odd #1 let #2 hang while you wind #3 nice and neat like #1, then fill in #2 even however you can get it to fit.

The original one Manual V and Trug came up with was nice, it eliminated some stator crossings but it always put the two strands BIG FAT ending coil winds next to each other, so my idea is to just alternate fat and skinny winds aka strand starts and ends evenly by pointing all arrows around the stator so they go start, end, start, end....... the starts always are wound first and evens are stuffed between, still leaving you the option to finish your motor even if you have to short the even winds by 1 turn to make it. As always stated before, circled #s are counter-clockwise wound.

Images

Feb 17, 2021, 11:17 PM
Registered User

Greetings from a Madonna fan hahaha

Hello! This is Tom Cross! I checked your work here and looks really awesome and great! Congratulations and keep up the good work!
And many thanks for your advices! I will definitely start rc flying and building!