Century 650A 545kv to low of a Kv rating for a HK600 in a scale application with 2 bl

[jimm]

Is a 650 545Kv motor to low of a Kv rating for this application? Looking to use in a Smartmodel AH-1 Cobra with a HK 600GT.

Thanks

[nightflyr]

What power do you plan on using?.....6,8,10,12S
And what target HS are you looking for?

[jimm]

I am open as to what C rating as I really am not commited to anything for electronics yet other than I do have the motor (Century 650A 545Kv). I would like to keep the cost of the ESC down to a reasonable level.

As it is going to be used for a scale application the Head Speed will only probably be in the 1500 to 1800 range.

Thanks

[nightflyr]

Ok figuring on a 6S setup..

545Kv X 22.2V = 12099 RPM
ALIGN 700 main gear 164T
20T pinion
164 / 20 = 8.2 GR

12099RPM / 8.2 GR = 1475 X 85% = 1254 HS
That may be a bit low for you

Even using a 21 T pinion you can only get to 1316 HS

So upping the batteries to 8S

545 X 29.6 = 16132 RPM

16132 / 8.2 = 1967 X 85% = 1672 HS

If your set to use a 545 Kv motor you will need to power it on 8S minimum for your desired HS.

As to a ESC Might look at something like this to save $$$

HobbyWing FLYFUN Brushless ESC 100A-HV (Version 4.1)



SKU: FLYFUN-100A-HV4

2 Reviews



Our Price: $165.99 $114.99

HobbyWing ESC Program Card for Flyfun & Skywalker



SKU: HW-PC

3 Reviews



Our Price: $12.00

[WildBird22]

For what its worth, I have an HK600GT in a Jet Ranger fuselage. Here are my specs on it:

Turnigy Typhoon motor with an 13T pinion turning around 1490 for a head speed at 80% flat throttle
Hobbywing 120amp ESC
Running 2 6S Turnigy (40-50C rating) 2650mAh batteries in parallel
Futaba S9551 low profile servos
Futaba gy520 gyro
Spektrum AR6210 receiver
Hobbywing 5-7 amp UBEC
Align Main Shaft, Main Gear, Auto-rotation Gear, Tail Blades, Torque Tube Assembly w/ tail box
Hobbyking Pro 3D CF main Blades
Dimension Engineering DELight kit
Flight time is 8 minutes but I try to keep it down to 6 minutes
Flying weight 10.6lbs.

Also, look into Low Profile Servos if your going to install it in a fuselage. Non Low Profile Servos can make the helicopter too wide to fit in a fuselage!

[jimm]

Wildbird22,

Which Typhoon motor are you using?

nightflyr,

Do you think a 1100 to 1300Kv motor would work better in it?

Maybe I should use the 545Kv motor in another application? Thought if I could not use it in my HK 600 then maybe in my Century Hawk mechanics with a 4 blade head to go in an Apache?

[nightflyr]

Originally Posted by jimm

Wildbird22,

Which Typhoon motor are you using?

nightflyr,

Do you think a 1100 to 1300Kv motor would work better in it?

Maybe I should use the 545Kv motor in another application? Thought if I could not use it in my HK 600 then maybe in my Century Hawk mechanics with a 4 blade head to go in an Apache?

If you work the math...
Say 1100Kv on 6S = 24420

Using stock 600 main gear..
170T / 14T pinion = 12.14 GR

24420 / 12.14 = 2011 * 85% = 1709

Which will get you your desired HS

A 4 blade head will require a slower HS so yes that would be a viable option

[WildBird22]

Originally Posted by jimm

Wildbird22,

Which Typhoon motor are you using?

nightflyr,

Do you think a 1100 to 1300Kv motor would work better in it?

Maybe I should use the 545Kv motor in another application? Thought if I could not use it in my HK 600 then maybe in my Century Hawk mechanics with a 4 blade head to go in an Apache?

The Typhoon motor I'm refering to is the Turnigy Typhoon 600H Heli Motor 1100kv

https://www.hobbyking.com/hobbyking/...00_class_.html

Your 545Kv motor would be better on a multi-blade rotor....with the right pinion.

You can see some of my test flight with the HK600GT in the Jet Ranger fuselage, and in pod-and-boom setup on my youtube page http://www.youtube.com/user/WildBird202