Found One Motor for Logo XXtreme

[garfieldhummer]

New KDE Out Runner very very very powerful to wake up the huge heli

KDE Direct 700XF-495
Kv: 495 rpm/V
Maximum Power: 10,000+ W
Maximum Efficiency: 92%
Maximum Voltage: 67.2 V (16S)
Io (@10V): 1.7 A
Rm (Winding Resistance): 0.014 Ω
Maximum Speed: 35,000 rpm
Rotor Poles: 8 (12 Pole Stator)
Bearings: Quad, 698ZZ/MR148ZZ
Mount Pattern: M4 x 30mm, M3 x 25mm
Shaft Diameter: 6 mm (8 mm Internal)
Shaft Length: 41 mm
Motor Diameter: 55 mm
Motor Length: 75 mm
Motor Weight: 670 g
Cooling System: High-Volume Radial Fan
ESC PWM Rate: 8-12 KHz (Outrunner Mode)

[int2str]

I thought the XXtreme needed something like this:
http://www.f1fanatic.co.uk/wp-conten..._fo108t_f1.jpg

[dahld]

Specs look very impressive. But before you go out and get one for the XXtreme, note the kv of the motor at 495 is far to high for the XXtreme's gearing.

We have played with motors as high as 410kv on 14S, and although as the kv's get higher and the power goes up, the down side is flight times start to suffer.

I haven't done the math, (so this is just a WAG), but the motor might "technically" work on 12S with the higher kv, but performance on 12S in a 800 class heli just doesn't hack it.

(-: Dave Dahl

[garfieldhummer]

Thanks a lot, buddy

What motor tooth do u use?

KV 495 * 14T * 3.7V * 14S / 175T = 2051

and this is a good number for someone who want to governor at 1900rpm, isn't it?

[dahld]

"KV 495 * 14T * 3.7V * 14S / 175T = 2051"

Kyle is running a 380kv motor, which I suspect will be available from Scorpion in the future.

The pinion in use is an 18T. This large pinion / large main gear set-up is intentional, as part of what makes the gear train of the XXtreme so tough. A 14T I doubt is in the works.

Also, even if you had a 14T, 2000+ head speed is not really doable, as the power to push an 800 class disc at those head speeds makes flight time too short. The mechanics are fine @ 2000 (we've tested that), but the short flight times makes it not a viable option.

Remember, 2000ish head speeds are what 700 class helis use for hot 3D (-: You can't think of an XXtreme as a "700 class", and transfer data, equipment, and "what works" over from one to the other (which I think many guys still do unintentionally). It's a whole new deal.

(-: dave

[garfieldhummer]

Thanks A lot, the 18T does make sense

haha, seems there is something hasn;t been shown to people now， like the motor from scorpion, hope it is a powerhouse as the HK45 series.

One more question, what is the head speed on XFC ? 1700 or 1900 rpm ?

Because some guys might thought it still has some head room for enhancing performence.

[dahld]

Head speed at the XFC was 1800, swinging 813 blades.

Kyle will be flying a different set-up at the Masters. Smaller disc, higher head speeds, and more collective pitch.

(-: Dave

[GimpyGolden]

Smaller like 700's?

[Nko15]

Maybe 753's or 793.. edge is working on those blades.

[GimpyGolden]

753 cool, may be hope for a 12S setup yet.

[marcosp]

Are 813s similar to what 713s would fly like in a 700?

[jhheli]

He has said any other post this is not a 12s heli. It is a 14s helicopter. When I first learned about the XXtreme I had planed to do 14s 753s 2050 headspeed with 115mm tail 12.5 degrees pitch, this is what I thought he would've competed with at xfc.

Hey Dave, you said in one post that there isn't a whiplash effect on the tail, is it because of the disk size on the tail, or do you think it is because of the dampened tail system, also with the smaller main blades, are you using smaller tail and is the whiplash effect still not present?

Originally Posted by marcosp

Are 813s similar to what 713s would fly like in a 700?

I highly doubt it, because from 610s to 710s on the same heli would drastic.

[garfieldhummer]

Originally Posted by Nko15

Maybe 753's or 793.. edge is working on those blades.

I guess 793, if it is 753 well which is like you cut one 700 class heli from 710 to 650, the flight would be greatly different.

And Mikado said just cut down the HS a little bit, so 793 has more possibility.

Haha, can;t wait to see Kyle ' s XXtreme on 3D master

[dahld]

@ jhheli,

Quote, "...you said in one post that there isn't a whiplash effect on the tail, is it because of the disk size on the tail..."

I'm thinking it's the "total package" of the design, but the size of the disc I'm sure plays a big role. The 115mm tail blades have a wider chord as compared to 105's (they're not just longer), and the spacing on the blade bolts is pretty far apart...so the tail disc is big, as well as the blades having a lot of surface area. Combine that with a 5:1 head-to-tail ratio, a large diameter well supported boom, strong drive system, and the V-Bar's tail control, all add-up to a very strong and consistent tail.

Kyle is using the same set-up on the tail with the smaller disc. The only changes on the heli from the XFC to now, are the disc size, head speed, collective range, and some "V-Bar tweaking" to accommodate the changes.

(-: Dave

[Nko15]

Originally Posted by dahld

Kyle is using the same set-up on the tail with the smaller disc. The only changes on the heli from the XFC to now, are the disc size, head speed, collective range, and some "V-Bar tweaking" to accommodate the changes.

(-: Dave

So what blades is he gonna run?


@jnheli, are you coming to 3dmasters?

[jhheli]

Thanks Dave, I am not coming to the masters, I wish it would come to the states, looking at all the competition, this will be one of the best events.

[Joe90]

I dont like the Poles/Slots combination, 8 poles/12 slots.
Why ? because the bemf and winding factor are not that good.
Kontronik, Xera, Scorpion, Neu have better combinations.

This suggest the designer overlooked something or chose the save on magnets. and compensate somewhere else

[dahld]

@ Nko 15

Q: "So what blades is he gonna run?"

A: Edge FBL 753mm's.

(-: Dave

[Nko15]

Originally Posted by dahld

@ Nko 15

Q: "So what blades is he gonna run?"

A: Edge FBL 753mm's.

(-: Dave

Thanks, I'll measure them at the 3dmasters to make sure he is not cheating..

Originally Posted by Joe90

I dont like the Poles/Slots combination, 8 poles/12 slots.
Why ? because the bemf and winding factor are not that good.
Kontronik, Xera, Scorpion, Neu have better combinations.

All the 50- series have that.. you are forgetting that its a large diameter motor.. i think they used wide magnets to counteract what you are describing..

Maybe Dave can confirm if the motor used suffers from cogging?(cogging is the sideeffect of less efficient magnet/slot count)