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[rathikrishna]

friends..modellers..Colleagues..when we looks for a good motor for our craft, the craft may be in any segment, we instantly looks around shops..and purchases some motors all, its specifications up to the manufacturer..and the final result become, like, slicing our feets to a newly purchased chappals..in some cases there is not an option, but to suit the purchased materials for our craft..but, if we have a little interest in some self research, we can rework some brushless motors all up to our specs.here i am reworked on some motors, for my new crafts, as a 3D plane, a working boat, and a huge tug boat.
          The main criteria in using a brushless motor, is all related to the current consumption..in aero modeling, it is not much possible to control the Amps consumption, as it need a full power in need..but in boat and ship modeling, it is very clear that after a particular RPM, the Cavitation will start to play, and the power will wasted..i was expirimenting a lots on this..and found we were wasting a lots of battery power in the form of cavitation, and inapropriate prop size and angle of attack..this prop related problem can be easily eliminated by, adding a self made prop, so can adjust the pich and size to all by trial and error methods..i usually gets ample of running time because of this..
        when we consider the brushless motor set up, its clear that the out runner motor is far superior to any brushed motors, in size to power ratio..so, we can choose any outrunner motors to our needs. so, we do not need a high current consuming motors..one of the great source of brushless motors are, yes the old faithfull VHS VCRs..but such motors can be fitted only on big crafts because of it's Gyroscopic effects. but, can add a reduction gear, to opposite side of rotation, thus eliminate the thrust effect of such huge out runners.but a craft like Tug boat, Tow boat, or on a working boat, its a great choice..after reworking, such motors drops within a 1.5 Amps, and a mere 6 volts is far enough for a big craft..

[rathikrishna]

                      another source of a good brushless motor for our crafts is..yes..the CD Drive of a PC..it is a very very versatile piece of engineering, and can be used in small aero models, and to me it is a greatly proven one in medium sized boats up to 3 feets,  and scaled warships..about 1:300..we can get a CD drive from many source, at free of cost, as many shops are keeping it as a waste..in boats we can use a simple reduction gears on it's shaft, so can avoid prop cavitation and it also generates immense torque to crafts..because of its compact size can add three or more in a craft..a carefuly reworked CD drive motor,drops only about 2 to 3 amps in load, so, two similarly wound motor can driven by a single ESC rated at theoratically 25 Amps.. cool..and my self research proved it works nicely for hours..
                     another positive criteria using a CD drive motor is it's mounting..we can simply drill a hole on a heat sink, so can simply fix the motor base on the heat sink..so, can add water cooling easily..
                     Here you can see , that a best source of huge immensly powerful motors are old VHS VCRs..here in my place many shops owners and home owners are too happy to give their old unused VHS, to me as there is no any source of VHS cassetes..so, i wonder, because, once a G10 ES from National panasonic was rated here as 18,000/- Rs once..but such machines can be found as a good scarp in scrapyards..usually i never ask scrap dealer for motors, because, if i ask for a motor alone, they ask me a lots of money for it..intead, i simply weighs the whole VCR, as a scrap, and they took the money in ratio as Rs 5/- for a Kilogram..hi..hi..

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[rathikrishna]

another good aspect , related to dismantelling a VCR or a CD drive is lots of useful stuffs like high quality silicon/nylon gears, heavy and light, rubber grommets,linkages, bearings, and many useful electroniccomponents, some good brushed motors, and yes..un imaginably extra ordinay screws..

now, i revomed the main head, from an old VCR, for my new Harbor tug boat. in my mind, the criteria about the motor is very torque, with less RPM, while with a very little current consumption..
so, i removed the original winding and can see the bare stator..

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[rathikrishna]

after ensuring every thing is in shape and ok, start winding..here i used 30 SWG HD copper wire, costs about 30 Rs/- here for 50 gramms in weight..
as the STAR (WYE) configuration gives us more torque, with less Amps, i choose the STAR..can also go for DELTA..for high k/V yes with high current..so, can see three folded ends and three starting ends..

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[rathikrishna]

winding in close up..see how simple it is..to do..
and reinstalled back on hub..

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[rathikrishna]

usually, we think that the original magnetic rings are too feable to copwith..its all wrong..we can add more powerful Strontium or rare Earth magnets, but, here we do not need any modifications..on magnets..
the out runner is back..later i churned out about 2 mm from main shaft, to drive a bicycle spoke nipple on the shaft to incorporate the drive shaft..
Now..time for check out..it is too easy to make an own ESC for brushless with reverse, but here i used a commercially avialable ESC, to save time..but at the time of installation will add a specific ESC, with reverse..

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[rathikrishna]

another good motor is from the direct drive of a VCR..this one is for my new Harbor tug, is more than a 3.5 feet long..yes, this one is massive, with it's 3.5 inch out runner cup. for this motor, we must use a good reduction gear, that the prop must turn in opposite direction to the motor, because of it's Gyroscopic effect..the prop also must be in big size..
can see the original winding is too light..

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[rathikrishna]

after removing all older winding, and started new winding in phases..with 26 SWG HD copper wires..this time also i choose STAR, as it can gives us a great torque with less Amps..

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[rathikrishna]

now..winding is complete..it took about 20 minutes to wind all poles with a song..and a cofee..
i removed bulky back plate from motor and can see the hub, is attached to motor stator, so it became so easy to fix on a craft..and this one need not a water cooling or so, because all time it will be it's under power ratio, as this RPM and torque is far enough to pump out the massive craft in to a nose up drive..with a 3 inch hand made prop..

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[rathikrishna]

we all know, to get a high torque and RPM, we always need a huge, or extra ordinary battery packs like Li Ion, or LI Poly..here can see i am using a simple 3.2 Amps SLA, battery at 6 Volts, then can see the motor rises up in a high RPM, while droping only about 200 m Amps..
and its too hard to sto it..even at 6 volts it is not possible to hold the drive shaft once..but i tried to give some load with my fingers..then can see it drops onle about 900 mAmps max..at 12 Volts this one is dangerous to hold in hand..while testing i used the full face cover helmet..and jacket..

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[rathikrishna]

this one can be used in big planes like gliders, and FPVs..as it is 50 Gramms less than the motor i used in my FPV once..and it is sure, this one can spin a 12 inch prop at ease..   up to this time we saw big motors..
now, one of my favourite series..once tried..addiction guaranteed..yes..is all CD drive motors..it is far capable, in the role of aero modeling and boat/ship modeling..it is very suitable for scaled ships, especially a craft with narrow hull..and is also suitable to make thrust pumps, and water pumps..when rewind with 24/26 SWG HD copper, it can out run a speed 400..!!! but still looks tiny..and shy one..at 7.2 volts it is far capable to spin a 9X6 slow fly prop at ease..to me..it is a piece of chiese..yummy..very powerful for boats..un imaginable..witha size of a coin..it is a true monster in performance..and yes all with a very less current handling..yes..very..very..less..
source of all CD drive motors are..yes..CD drive itself..if you have two or four same Cd drives..your boat or aircraft will dance in water or in air..
can see a good motor here..i always beggs for these unused/burnt drives to all known outlets..friends..any way..
remove it from base..

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[rathikrishna]

we can rewind these motors up to our specs..it will work from 6 volts to 12 volts..can alter RPM,Wattage, Torque all up to our needs..to me its all for my boats and ships..so, my motors will be within 3 to 4 Amps max..but within this max limit it is un imaginably powerful..so, it is clear that this motor set up need a reduction gears on boats..
we can rewind it all up to our specs..and can use as it is..

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[rathikrishna]

despite it's size..it is too capable..i will add all test and running videos of all motors..but not now..my connection speed is too low..but will add later..and hope it is not need to add all rewinding steps here as all of us are know about the rewinding proses..see once..how easy to rework on a motor..it is too easier than rewinding on a brushed motor..and ultimately powerrful..and we do not need any complicated machines..or a strict rules..just rework it all..fix it forget it..this tiny motor is far capable than a commercially available 1000 RPM/Volt motor, on my boats..still drops very less current from battery, to a same given speed of the craft with same prop..so..?  long live battery..ample of running time..hours of RCying..

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[rathikrishna]

adding some videos..

http://www.youtube.com/watch?v=FZ7ip-PxFsg

[Martin (Admin)]

Sorry krishna , I've accidentally deleted some photos, please can you repost them and I'll move back to the right place.   

[Circlip]

 Some (?)

     Moderation taken to the extreme ????   

  Regards   Ian

[rathikrishna]

sure Martin sir..its a painstaking proses..with poor speed connection..still try..thank you..

[rathikrishna]

Martin Sir..once again adding the photographs..

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