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Because the half parallel dLRK wind doubles the Kv of the dLRK wind, I don't think anyone here has ever terminated one Delta. It would simply get the Kv way to high for any of our uses. Look at the different winds do to a motor that starts as a 750 Kv in the attached.
When we rewind a motor we are usually getting more power and may want a little bit higher Kv to take advantage of the extra power but never double it. At least that is how I see it... Jack |
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Thread OP
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iPower iBM 5208q 30t 20awg 361kv hpdLRK wye 52x8mm stator.35mm plates iflight-rc.com
Finally decided on the hpdLRK wye adjacent coil wind 30 turns of 20awg (11amps) motor 24 volts A123 -- 22 amps 528 watts max.
This power limit should be OK since I will be trying for best efficiency I wondered how to keep that adjacent crossover neat, hold it inside center with string to do the first layer. Here's more explanation of my wiring diagram and has almost all the winding guides we use. new diagram system LRK - dLRK - Evo dLRK - half parallel dLRK https://www.rcgroups.com/forums/show....php?t=2608773 Leonard ImagesView all Images in thread
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Last edited by leonard3k; Sep 15, 2016 at 03:32 AM.
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Was it clean and cool because he had not taken a pee it is yet?
Off topic but look at what I found: http://www.armstrongmetalcrafts.com/...SizeChart.aspx The info you'll see there is interesting and useful enough, but click on the References link to see how really useful that page is! And there are not any pop ups or advertising! That page is going to replace visits to about nine places I used to go to! Jack |
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Thread OP
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Finished winding 30t 20awg with the hpdLRK adjacent coil method.
I thought that crossover would crowd, but I determined to fix that. Holding the wire with string kept it mostly on bottom of the coil it started from. This pattern 13 + 10 + 7 meant no overlap inside. Try it this way for this hpdLRK adjacent coil wind, works very good. Has anyone made up one of those neat colored winding diagrams yet for THIS VERSION of the hpdLRK wind...adjacent coil wind? If yall get one I'll add it to my collection of all winding diagrams for everyone to use as reference. Each coil pair was epoxied when finished just in the middle. The wire end always comes out in the middle at the end after winding the pair, so only one wedge is needed to hold tight while epoxy cures. Sidney often lays in the litter box but only if it's clean. Leonard |
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Last edited by leonard3k; Sep 16, 2016 at 02:21 AM.
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Thread OP
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iPower iBM 5208q 30t 20awg 361kv hpdLRK wye 52x8mm stator.35mm plates iflight-rc.com
Terminated and tested
4485rpm / 11.91v = 376.57 kv Io = 0.6amps This is still good though I did a test wind to be accurate and neat and missed no turns but, looking at the chart it's OK I think I got 30 full turns on the six starting teeth of each strand and 29 turns on each tooth ending the strand. The problem is that tricky turn count on the crossovers just like a dLRK wind, I counted the wires I saw at the top on the first layer 13 like the other but one turn is only half and not closed or even thought about...till now. To make this right seems I should have done 13 + 10 + 7 first then 13 + 10 + 8 on the 2nd tooth... is this right? Yes I know I need those battery packs done for 24 volts (12 + 12) and test motor for kv then prop test too. Manuel V, you first showed us this hpdLRK variation, so when you wind it do you always put an extra turn on the 2nd tooth in the string to get the intended turn count you calculated for? Like I intended 30 turns to make it come out right should the 2nd tooth have 13 + 10 + 8 where it just looks like 31 but one is just the unclosed crossover, hardly a turn at all? I know this goes back to the turn counting issue many people have with dLRK. Would you strictly exactly say what's on the 2nd tooth each strand is 29.5 turns? There was no effort to even close a half turn in the slot. Counted as 29 or 29.25 or 29.5 ??? Leonard |
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Last edited by leonard3k; Sep 17, 2016 at 02:10 AM.
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As I wind I always choose the placement of the transit run to the side of the bearing tube that fully closes or most fully closes the starting turn on that arm. The difference it makes is some like 1/4 of a turn on so.
I know it is a time honored character trait for machinists to be very anal retentive about some details of their work. It is starting to look like maybe the man knitter community has inherited that. I think you'd find that if you removed the stator from the tube, put a handle in it, and used something like the 3rd hand accessory to put a little tension on your wire as the turns go on you'll get more compact winds. Of course, that is also the "my way is a better way to do it" trait, also inherited from my master machinist father... And if you were working in my shop the "do it my way or pack up your tools and leave" trait would be looming over you... Anyone else remember the old Bull of the Woods cartoons? I think those cartoons contributed to my work habits around and interactions with my Dad and Grandfather. They were humorous but they also often had a valid point about safety, harmony in the shop, and other important life skills in them. Jack I loved those |
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I count turns.
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Thread OP
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8 grams of thrust per gram of motor weight
5208 pancake motors take up a lot of space
So I'm thinking of trying EMP 4260 and or iFlight 4120 x motor Looking at it the way that highlights thrust obtained per gram weight of motor 3508q 586kv 114g rewound 907.2g thrust 32oz for 102 watts gws 12x8 ep How hard do you squeeze the motor for the thrust? 8 grams thrust per gram of motor, and this for about 9 grams thrust per watt. Apply to 4 # thrust says 2041g / 8 = 255 gram motor at least. 24v using apc 14 x 8.5e prop Scorpion 3520-700kv chart 5982 rpm 1915g thrust 67.55 oz 48.2 mph This gives a good approximate goal Using 24v to get more watt-hours 350 - 360 kv would work EMP 4260 is 267.5g stock n 280g 9.9oz after rewind 13t 22awg hpdLRK delta 516kv (Ronaldopn) and would easily rewind to 350kv and 250 watts / 24 volts 10.4 amps so I'd want to be able to rewind with a minimum of 21awg 9 amps x2 = 18 amps max hpdLRK wye EMP C 4260 step by step rewind https://www.rcgroups.com/forums/show....php?t=2728652 I know 250 watts seems low and might not get 4# thrust for 9 g/w or 220 watts or 10.5 amps at 24v BUT I'm sure going to try and see how cheap 4# can be had for (airplane speeds, not multirotor ) I want to try spinning a 14x8.5 to 5980 rpm for 220 watts on 24v. ...not expecting too much, huh? Iflight-rc 4120 is 336g stock 11.85oz quite a bit more than needed Most of you approach the other way around telling how much power throughput you achieved or other variations like 3g per watt Here's an analysis of the ratio of thrust to motor weight. Emphasis on getting 4# thrust at or close to the rate of 9 grams per watt and what minimum motor weight will do this easily. A smaller motor can be made to get the thrust but probably with a very low g/w ratio. Probably I'm adding more and have already got close to the motor that will do this with the 5208 but it doesn't fit the Hurricane so this new effort is for motors that will fit tighter places. Might use the 5208 for a fat nose WW1 airplane Leonard |
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Last edited by leonard3k; Nov 03, 2016 at 01:41 AM.
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Thread OP
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Earlier I didn't think about the motor circuit and that max current could be calculated so easily
Starting with the day I figured all the circuit types and current depending on wire rating, hpdLRK: delta 3x and wye 2x dLRK: Delta 1.5x and wye 1x So the Scorpion 2215 I wound 11.5t 24awg hpdLRK wye 962kv will only have max current rating of 7 amps, it gets hot easily with a gws 10x6 ep if driven wot Some low power motors I've wound are like this. ..close to the limit also creating losses from heat and increased resistance. Below I made another chart because so many times we have to consider current limit as well as what wire fits the motor. Now I'm working up slowly to the challenge of more thrust, double at 4#, and considered that power requirements for thrust may not be linear (2# 102w and 4# 204w). It may be easier to get closer with the 5208 at 376.57 kv weighs 228 grams (8 oz), after rewind hpdLRK wye, it's short 25g by the weight idea but the larger diameter stator may be best for this goal Iflight 5208 is 30t 20awg (11 amps) 376.57kv hpdLRK wye 22 amps max 528 watts max on 24v I only want to burn HALF of 528 watts for 4# of thrust! EMP C4260: 280g (9.9oz) 35x33.5mm stator iflight 4120: 336g (11.85oz) before rewind 41x20 stator This iFlight 4120 is like sticking a 12 oz can of soda on the nose of the airplane For comparison my 10cc 0.6 cu inch evolution 10gx weighs about 30 oz with battery. ....and I only thought it would be just a little heavier than my Saito 0.52 four stroke! !!!! Way over budget! The 10cc evo is for my Sig somethin extra The only 2 engines I've ever flown evo 0.40 and Saito 0.56 four stroke (11x7 props) Anybody have any links to engine thrust tests for comparison to electric Leonard |
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Last edited by leonard3k; Nov 03, 2016 at 12:25 PM.
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The value of amperes marked in this table is very conservative.
motors can use much more current marked on it by wire. LBMiller5 has its own table, contains 3 values and still remains conservative. for example. 19 awg wire supports 43A. Post 34. https://www.rcgroups.com/forums/show...=565590&page=3 |
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