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May 06, 2015, 05:44 PM
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Originally Posted by DeadstickDuck
... So, what do you find is the deepest we can go for a battery, with 34mm wide and 17mm high being the standard 2s brick maximum. Perhaps, if you want to spend the time to fashion a blank out of balsa or a quick cut of 2x4 lol.....that's what I do,.....that would be awesome. Let me get the TP 2s info off the web.
Sorry DSD .. can't be done simply, I'm afraid. My SB is fully configured (for sloping) and I have a servo tray ... with two servos .. and two rods ... and a ballast tube .. all blocking the way into the fuse. However, I'm pretty confident your battery mod will take care of it.
By the way, just as a check, how did you configure the balance lead? (I'm assuming a common ground and then each +ve wire from each consecutive cell goes to consecutive pins on the balance lead?

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May 06, 2015, 05:49 PM
Registered User
Originally Posted by DeadstickDuck
Sketched a top down view of the fuselage from nose to CG.
There simply is not enough room for anything but 28mm outrunner like the Cobra 2221-10 spinning a 30x4x8 10x12 prop on a 3s2250mA 45C.

The motor here is a Suppo 2217-7 laying around and used for reference only.
No room for the elevator servo? What about your split battery config for getting the battery underneath the wing saddle?
May 06, 2015, 06:30 PM
Ya, I think there will be room for both rudder and elevator servos if the ESC can slide up one side of the fuse, the Talon35 is pretty small considering.

Wiring the 2s packs for correct 4s balance connector is not too much trouble, no soldering needed. I will draw a wiring schematic....

Found one...

The main power lead between cell 2&3 is flexable.

DVM should show:

Pin 1&2= 3.7v
Pin 1&3 =7.2v
Pin 1&4=11.1v
Pin 1&4=14.4v
Last edited by DeadstickDuck; May 06, 2015 at 06:42 PM.
May 06, 2015, 11:34 PM
Registered User
Thanks for that.
Originally Posted by DeadstickDuck
... The main power lead between cell 2&3 is flexable.
... and needs to be a very solid connection! There's a lot of current going through there!
Did you solder the main power leads together .. or one lead directly onto the other's battery tab (opposite polarity)?

PS: Ok .. found your post on the Kunai thread which explains how you did it here. All cool.
Last edited by Flightplan; May 07, 2015 at 12:58 AM.
May 13, 2015, 10:13 PM
Still waiting on my order with no ETA from HK and holding off on 6x servo until I have the fuselage in hand.

Will she be overpowered if I can run her on a 14x9.5 and 2s5000 ....on the hyperion gs3025-04 1540kv
May 14, 2015, 03:12 AM
Registered User
Originally Posted by DeadstickDuck
Still waiting on my order with no ETA from HK and holding off on 6x servo until I have the fuselage in hand.
A 30x30x10 (mm) servo is a pretty tight fit in the wing pockets (ailerons and flaps). The newer, smaller, digital coreless metal geared ones 24x20x8 (mm) are ideal however, (if you have a choice, that is).

Originally Posted by DeadstickDuck
Will she be overpowered if I can run her on a 14x9.5 and 2s5000 ....on the hyperion gs3025-04 1540kv
What does "overpowered" mean?
May 14, 2015, 05:10 AM
All my eCalc estimates has me leaning towards my Hyperion Gs-3025-04 on 3s and AR10x12. With a 3s3300mA 70C it should be good for 99mph vertical and 125 level speeds at @135A. With the over-current set at Insensitive (170 amps 5 seconds) and a separate CC 10A BEC for the radio...the ICE 100 should work well on this setup....5 seconds of WOT the darn thing will be a dot.

My ICE100 has handled 120A many times with a Rimfire 1.20 @2300w......

It really is a mystery if the slope version fuse is going to be too narrow for an outrunner with the diameter of 37.5mm to fit, the tapered nose of the Hyperion GS motors is the only thing that might make it fit.
Last edited by DeadstickDuck; May 15, 2015 at 07:59 AM.
May 15, 2015, 01:38 AM
Registered User
Knew I should've kept away from this thread ..

Just took another 'plunge' and picked up a pre-loved E-Sunbird!

It comes with a GS 3025-08 867kV Hyperion and a 16x8 prop. (Gotta wait for a week or so before it arrives).

Wish me luck, eh?
May 15, 2015, 07:49 AM
Life is good!
strat1960s's Avatar
DSD and Flightplan,

You two sound like you're having a grand ole' time in here. Two mad scientist working together. You should call your SB Franken-birds! I call the 1965 Mustang in my profile picture Franken-stang.

Have you received your SBs yet? I'm sure you're chompin at the bit to get started.
Cant wait to read more.

May 15, 2015, 08:03 AM
Nope...still un-updated status of "Printed and in cue for pull".... That order went in and was paid May 2nd.... 13 days ago.

That's one slow a$$ order puller.
May 15, 2015, 08:06 AM
I'm sure my Sunbird will be better than a base Sunbird E setup. Maybe even lighter with more power. It's my thing.
May 15, 2015, 08:15 AM
Worse case scenario I split the front and add a few more mm in diameter.
May 15, 2015, 08:26 AM
Servo question: Just how much torque is good for this type of hotliner? Mine my hit 150mph in power-on dives.

My rule of thumb is a digital servo with torque in ounces equal to model weight..... So, 52oz means 50~55oz torque.

I have 3 MKS Ds480 @32oz each and 0.07sec speed. They might work for ailerons and rudder.
May 15, 2015, 11:46 AM
Well.... HK did not have an ETA for my Sunbird and I'm done waiting..... I ordered it 14 days ago.

I now have a Cyclone 2M bird on the way that is actually in stock ew and 17 miles away... Shipping better be under 2 days I tell you

So, sorry to bail but a 2M bird will be a good step upward. And no chopping off a nose.

Thank you for the help Strat1960s and Flightplan
Last edited by DeadstickDuck; May 17, 2015 at 07:42 AM.
May 15, 2015, 04:24 PM
Registered User
Whaa?? Abandonment?

Can't say I blame ya there, DSD.

Tell ya, its also a bit weird that during the HK sale, I had both a new SB sloper and a Cyclone in the shopping basket (at different times). I've also had a longer term idea of motorising the slope SB. Love to eventually get an E-Schwing too (if/when they ever become available).

Good luck with the Cyclone! I'm a bit worried about the CoG in the E-Sunbird .. it seems to always end up nose heavy(?) I think a lighter motor will ultimately be needed ...

PS: Oh .. I reject the 'Franken-bird' label for my E-SB! ... Sure works for the rest of my fleet ... but not the E-SB!

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