690sx - Adding weights for proper CG.

[acidla]

Hi Guys,

With my setup, stock motor, Edge 160 esc and 2x6s 5000mAh packs the 690sx is nose heavy.
I pushed the packs all the way back and the nose drops fast.

Where i have to put the weights, on the tail fin?

Cheers!

[acidla]

Ok, i got some lead weights and added 58g on the tail fin, now it balances fine.

[rcflyerheli]

With the light weight of the 690, it was recommended by Ron at Mikado to drop down to a 120a ESC and 4500mah packs.

I looked at the logs on my 160 and the most amps I have pulled is 127, so a 120 with the lighter weight ought to do the trick. I haven't had a chance to test fly the 120 yet, but will do so when the weather clears.

[acidla]

After the CG issue i thought exactly the same combo of esc and packs as you mentioned it

On a side note; with an Edge 120A and 5000mAh packs it will balance ok.

[mahbouni]

A metal tail box e.g Lynx or Hawk helps a little bit

[acidla]

Lynx got metal tail box? I only knew about the Hawk one.
Cheers

[Laughingstill]

Yeah, you overbuilt that one with the 160, just too much esc and batteries.

[mahbouni]

Originally Posted by acidla

Lynx got metal tail box? I only knew about the Hawk one.
Cheers

http://www.world-of-heli.de/en/lynx/...-logo-600.html

[doubletap]

Originally Posted by acidla

After the CG issue i thought exactly the same combo of esc and packs as you mentioned it

On a side note; with an Edge 120A and 5000mAh packs it will balance ok.

This is going to be my setup, so good to know that it will be fine, i have 5000mah packs which im using with my other heli, the the 60c eco power i am alittle worried about the weight of the 2 pack, the pulse is just 45c so its fine, but maybe in the future i will get some 4500 or 4400... Im just looking for a longer flight time....thanks

[acidla]

I can't wait to maiden this heli!

I am curious to see my amp draws from the Vbc logs.

[KevinB]

No need to add useless weight. Check out my thread in the other forum regarding cutting out the rear bulkhead from the battery compartment.
I'm flying with 5000mah packs, use a YGE160 w/heat sink, and have perfect balance with no extra weights on the tail.

I've had two crashes so far since removing the bulkhead and my frames are still fine. That was the one worry I had about removing that material....whether it would weaken the frames back there. Apparently not.

KevinB

[acidla]

Hey Kevin,

Will check it out. Cheers!