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B400flyer
09-24-2009, 03:28 PM
I would like to run my blade 400 ok a123 batterys but first want to know if anyone has tried it yet?

I'm thinking allready that I'll have to cut/mod the frame for it to work?

Thanks:)

meatbob
09-25-2009, 08:21 AM
I thought about it, but decided against it because I would need to hack up the main frame
or run a split pack. 4S would be a very heavy heli. 3S would be okay, provided that you run a motor over 4000 kV, like the Scorpion 2221-6 or the E-flite 440H, and gear it appropriately. Also, you'd need to set your LVC much lower so that you can handle the lower voltages. This rules out the stock ESC, as the LVC on that is too high.

A123 cells are rather large, so you will need to get creative when mounting them. I have not tried it, but the promise of fast recharges is tempting. Since the Hyperion G3s came out, A123s lost some of their luster.

B400flyer
09-25-2009, 02:35 PM
well right now I'm running a scorpion 90amp esc with a Scorpion 2221-12 motor(2500kv?)

This would be to weak on 3 cell right? So should I use 4 cell


I also hacked up my frame a little and now I should be able to get 3-4 cell a123 bats in there pretty good.

Starcraft-IX
09-25-2009, 04:08 PM
a 90amp ESC??? Wow

With the lower voltage of the A123, you would definately want to run 4S, but it will be nose heavy unless you mount the battery differently.

meatbob
09-25-2009, 04:24 PM
4S is going to be heavy, especially with a 2500 kV motor. If you split the pack to two duals, and mount them on either side of the frame, you might be okay. However, I'd get a higher kV motor.

B400flyer
09-25-2009, 05:08 PM
Ok let's say I go with 4 cell with my current motor what pinion should I use? Right now I'm useing a 11 tooth and it's about 2000 rpm?

Thanks

meatbob
09-25-2009, 05:56 PM
Using the readyheli headspeed calculator:

140 tooth main, 11T pinion, 2500 kV, 20C LiPo

3S LiPo - Avg Headspeed 100% Throttle = 1957 RPM

4S A123 - Same Pinion, Avg Headspeed, 100% Throttle = 2593 RPM

Since you are running a 11T on a lower kV motor (higher torque, btw), you'll probably be okay on battery life, but I really don't know.

ingrahal
09-25-2009, 09:53 PM
Do some searches on it. I found quite a bit of info some time ago but didn't save any of the info. Sorry. There were a couple of guys doing it though.

Tode
10-02-2009, 03:22 PM
I run 3s1p a123, 40amp esc, turnigy 3700kv motor rewound 5t (same as factory but more copper),13 tooth pinion. Dont know my exact flight time max timer set at 5 min never notice drop during flight. Can fly full throttle curcuits for all five min or soft 3d (pilot cant do the hard stuff yet) zip charge at 10-12 amps can fly almost non stop with 2 packs.

everydayflyer
10-02-2009, 04:09 PM
My son uses 4S 1100 A123s with stock motor and pinion, CC Phenix 25 ESC ,fixed governor mode 2550 HS , CF baldes,4 min. flights FFF and is learning 3D.

We data logged a flight yesterday, hard punch outs, kinda tick tocks, FFF, flips,flips to inverted and punch outs. .

Charles

B400flyer
10-02-2009, 04:55 PM
I'd like to use the 2300mah a123 cells but is there a big difference in size from the 1100?

Thanks

Starcraft-IX
10-02-2009, 05:11 PM
yes, significant size difference. Just over twice as big

everydayflyer
10-02-2009, 06:00 PM
I'd like to use the 2300mah a123 cells but is there a big difference in size from the 1100?

Thanks

Understood but the 1100s are so simple and weigh less than a 3S 2200 LiPoly. Charge at 5A in less than 15 minutes, last 500 plus cycles, no special care required.


Charles

meatbob
10-02-2009, 06:34 PM
The 1100s will sag quite a bit under load. You averaged 11V under load, which is interesting for 4S. Thanks for the data! I did not see the crash in voltage towards the end of the pack, which suggests that you were flying conservatively at the end. That's been my fear with A123 is the fast crash at the end of the pack.

How many mAh went in at the recharge? Also, it would be interesting to see a 2221-6 with this setup. I suspect the voltage sag would be more remarkable.

everydayflyer
10-02-2009, 06:56 PM
That flight was only 3 min.My son normaley flys 4 min. but there is no voltage drop till the cells are empty. In a 4 min. flight he uses 800 to 850 mAh. Set and use a timer. Capacity used is in the legend on left . That flight 646 mAh used. Last minute was FFF and Blade 4oo just does not pull that much then.

Best source fro the 1100 cells is from DeWalt 18 V packs from E Bay.

This is the one and has 12 cells in it.

http://www.rcgroups.com/forums/showpost.php?p=9999992&postcount=1

xspare
10-02-2009, 10:17 PM
Wow, do you like 2000 RPM? Does the tail hold? Any vids?

I ask about the tail because I accidentally ended up running 2150 RPM last month and the arse end of the heli was drifting all over the place, back up to 2600 RPM and the tail is locked in.

Ok let's say I go with 4 cell with my current motor what pinion should I use? Right now I'm useing a 11 tooth and it's about 2000 rpm?

Thanks

B400flyer
10-05-2009, 09:47 PM
Wow, do you like 2000 RPM? Does the tail hold? Any vids?

I ask about the tail because I accidentally ended up running 2150 RPM last month and the arse end of the heli was drifting all over the place, back up to 2600 RPM and the tail is locked in.
I don't really like 2000 rpm mostly because the tail does not hold that great but at least the battery life is good (7-8 minute flights)

Also I do have some vids on you tube just search my name (B400flyer)

Epoweredrc
10-06-2009, 12:09 AM
Here is a video of mine on the 4 cell 1100mah packs my father posted about. I am doing full flying, loops,rolls, stalls,figere 8's and what i call mild 3D flips, sort of tick tocs, flip inverted with hard punch out while doing peros. I am quite happy with the set up sure I could fly a 3 cell lipo and get 6-7 minutes but why, 4 minutes is plenty and with two packs i can fly back to back ( it takes a few mins walk to and from flight line, and take canopy off and on. I get wore out fly back to back as in no resting plus i take turns with my father when I fly with him.

I have 150 cycles and 110 real flights with mild 3D

YouTube - B400 june 24th

last video I posted.. check out my others on youtube.

B400flyer
10-06-2009, 02:38 PM
Thanks for the great info to all who have posted, I now have it down to 4 cell a123 1100mah. So I then was looking for places to buy the cell and I stumbled upon Hobby King and they have the 1100mah a123 cell for around $7-8 per cell. Does this sound decent? Also for those of you that are running a123 cells did you buy it premade or was I custom?

And lastly can everyone post there pics of there a123 blade 400?

Thanks so much:)

Epoweredrc
10-06-2009, 09:13 PM
Thanks for the great info to all who have posted, I now have it down to 4 cell a123 1100mah. So I then was looking for places to buy the cell and I stumbled upon Hobby King and they have the 1100mah a123 cell for around $7-8 per cell. Does this sound decent? Also for those of you that are running a123 cells did you buy it premade or was I custom?

And lastly can everyone post there pics of there a123 blade 400?

Thanks so much:)

No problem, here is my B400 only thing I had to do was move the gromlets on the canopy back just a little ( my canopy is updated with magnets hate the gromlets)
but not issue. It blances just perfect. My father (Everydayflyer) builds all mine. there lots of threads on building your own packs.

B400flyer
10-06-2009, 09:20 PM
No problem, here is my B400 only thing I had to do was move the gromlets on the canopy back just a little ( my canopy is updated with magnets hate the gromlets)
but not issue. It blances just perfect. My father (Everydayflyer) builds all mine. there lots of threads on building your own packs.
No offence but you said "here is my......." and there is no pics?

Tode
10-09-2009, 06:44 AM
No problem, here is my B400 only thing I had to do was move the gromlets on the canopy back just a little ( my canopy is updated with magnets hate the gromlets)
but not issue. It blances just perfect. My father (Everydayflyer) builds all mine. there lots of threads on building your own packs.
Magnets? Got pics? I am using a Thunder tiger canopy. It's roomier and fits nice over the 3s pack but it needs some mod to fit the B400.

Epoweredrc
10-11-2009, 11:54 PM
No offence but you said "here is my......." and there is no pics?

Sorry I don't know where they went. lets try again.well wont let me post here cause there posted in another thread here is a link to it
http://helifreak.com/showpost.php?p=1376925&postcount=9

ingrahal
10-12-2009, 12:21 AM
The magnet thing is cool. How did you mount them on the canopy?

Epoweredrc
10-12-2009, 09:34 PM
The magnet thing is cool. How did you mount them on the canopy?

Well we tryed CA but it didn't hold long, so then used Goop (shoe goo) and it holds pretty well. I used small wood dials on the carbon rods drilled a hole in the dail slid it on the carbon rod and glue the magnets to the dail. works great I hated the gromlets they fall out and all also.

my dad came up with the idea.. i have had the magnets come loose after a while but only twice I belive over long pd time.