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View Full Version : 25mm 12arm 14p 18t 26awg 4x10x2 LRK AacCBbaACcbB


swatson144
01-20-2005, 08:37 PM
just tested my 1st distributed LRK. I am astonished! I want to point out that all wires are about 4" to long as I figured I'd want this thing Delta in the end but testing it wye was free. I am used to about 1.75 thrust to amps drawn. with the 9 arm 22.7mm, well maybe a little sweater with the right prop, or sour side with the wrong one, but pretty much right there. trying the 25mm 9 arms I started seeing around 2.3 t/a (thrust/current dc at the speed controller I like t/a pardon me if I continue to use it, please substitue any term that is more correct) which is much better for flying longer. Flying longer is fun as long as the motor exceeds min acceptable standards (whatever they may be) for the application. This motor produced a low thrust, which was expected (high turn wye), and was under propped with my biggest. A 10x7 APC SF, I didn't test anything smaller.

10x7 APC SF 160G thrust 1.9A 7.14V 1710rpm
160g 1.83A 7.14V 1710rpm

several more tests same same

no load .33A 7.81v 3500rpm

2.9 t/a

I don't know if the huge difference in rpm light load / no load is normal. Until JayC mentioned it, it never occured . Then :idea: . I should measure that! I'm slow but I am stupid!

I used leftover GB 4x10x2 magnets. the stator was a 5 stack 25mmx12arm GB. The can was made from the fluxring material thread, sans broaching (still working on that). The cogging with this setup is amazing. It feels like the tuning knob on a side control RCA television!

Somewhere around here I have some like 12x8 etc GWS eps props, that came with kits, and I'd like to test with them then configure the thing Delta and see how it goes from there.

If I'm fundamentally screwed up please point it out that others may learn, and me too. Questions? I'll try. suggestions I'll likely get there in time, but I'd like to hear them. Next is 10 mags same setup wye then delta. Gotta buy more mags and stators,

swatson144
01-26-2005, 09:37 PM
finished testing it in wye configuration.

GWS 12x6 (which is the biggest prop I'd consider using for my purposes)

255g 2.65A 7.8v 2640 rpm
3.4 t/a

It seems this motor should handle 10A easy. at 10A I'd get somewhere around 25oz thrust. I don't want a lawnmower blade on it though :(
My schedule is full for tomorrow, but I'll switch it over to Delta and test it, soon. I like it.

swatson144
02-01-2005, 07:27 AM
It's a delta now. I only tested it no load to see that it worked before potting.

7.8v .77amp 5910 rpm


Will test fully after potting hardens.

hubgar
02-02-2005, 04:51 PM
With less winds and larger wire, this motor could swing a lawnmower blade!. Your results look promising. hopfully, delta should give you the RPM you need.
I think 14 or 15 turns of 0.5 or 0.6mm, (aprox. 24-22g), wire would also help if you are going to use 2S li-poly.
I would like to start a 10mm thick LRK, as you have, but still working on the 5mm one.
HUBERT

swatson144
02-02-2005, 05:25 PM
5mm stack good! you post results and I'll continue with the 10mm. I intended to do some good things in the garage today but caught service call, coupled with the fact I found out my QC toolpost should arrive tomorrow. It kinda removed my motivation for any machining today. Sure will be nice to have a working parting tool! I have intentions of testing the motor after supper. Bought kero to feed the heater though so I got no real 'cuses.

I ntend to go to 3 cell sometime but magnets seem to attract all my $ for that.

swatson144
02-02-2005, 09:52 PM
got some testing done, this motor delta

GWS EP 8040
170g 2.1A 7.63V 5700 rpm

APC SF 10x7
365g 7.1A 6.7V 3780 rpm

GWS 12x8
480g 8.2A 6.65v 3510 rpm

The last one was fun! it kept trying to twist and pull out of my mounts on the test rig. Couldn't run it for more than about 30 secs before having to re-mount it. I see where this is going so I'll need to rethink my mounting methods. I've built a full symetrical aileron wing for an arrow shaft fuz (from a '60s plan for 049 called "the scorcher" and modified from flat bottom) looks like I'll need to finish that plane and use it for windy days, with this motor. Since I have rec'd an order of GB stators I am going to agree with Hubgar and make a new stator and bearing tube ***'y with multi strands of 28g I got in my last order ~14-15t. Tests to follow.
.,.,.,.,.,.,.,.,.,.,.,.,.,..,.,.,.,.,^^^^^
Thats amusing... the cursing was an abreviation for assembly :)