C Ratings and my bad batteries

danwholio · Posted: Fri Dec 03, 2010 6:41 am Post subject: C Ratings and my bad batteries

Ok, I've got some issues going on with my T-rex 450 and my batteries. I just bought a 450 se v2 off of Ebay and received it in the mail about a week ago. It came with 4 batteries, a huge amount of spare parts, and a JR xp9303 radio. The guy said it was all "ready-to-fly", but it was about as ready to fly as a hunk of rock.

The tail servo was burned out when it got here. Two batteries were swollen and one of them blew up on me right after I disconnected it from the heli ( it wouldn't provide enough power to get off the ground and I noticed it swelling). So, I was left with 2 batteries that would actually charge and work. I used both batteries on Sunday and on Tuesday. I went to fly today again with both batteries, but one of them became swollen after about 8 minutes of flight. Before, that same battery gave me about 12 minutes of flight and never swelled up. The hobby shop says that no one uses batteries with a 25C rating anymore and my T-rex is probably draining the battery too much.

I'm using Thunder Power 11.1V, 3 cell, 2070 mAH, 25C batteries. They recommend that I buy a couple of 45C 2200 mAH batteries. They said the 45C would most likely not puff up and blow up like my older 25C Thunder Power batteries. Thing is though they want like $70 for one battery and in my opinion that's a fairly steep price to throw down on a battery that may or may not puff up and explode as well.

For Crashagain and Trouble... I might never fly my 120 sr again, or any other bird that's of lesser quality than my 450. I never new what helicopter flying was about until I got this awesome set up. I am practicing back flips now and I am able to fly out up to 200 meters with great control. Winds today were 30 mph and the 450 did great... didn't blow around or anything, just sliced the air like butter!! All I need now are some dependable batteries, but man they are expensive!

tombo242 · Posted: Fri Dec 03, 2010 6:51 am Post subject:

Hi Dan,

If you don't mind waiting a while these batteries will save you quite a lot. They are in the USA warehouse so delivery should be pretty quick.

I can't see that you really need 40C but at this price ($21.99) try a couple and see. I'm using these at $11.44 in my EXI 450 with great success but at 20C may not be enough for you.

Tom.

P.S. know how you feel about the tiddlers but when it's wet and windy it's good to have an indoor heli. Cool

sbobby · Posted: Fri Dec 03, 2010 7:40 am Post subject:

I bought 4 Turnigy batteries 2200mah, 20C for my 450 Trex clone from HobbyKing as well.
They are pretty good (to my standard anyway) but I don't fly 3D. They hardly get warm after flying nore than 10 mins.

oldmanflyer · Posted: Fri Dec 03, 2010 7:43 am Post subject:

Hi dawholio, How did you pay for the ebay heli, if you paid by paypal and the desription said that everything was in good condistion, you can get the seller to pay you back for the cost of the deffective parts. I did it and the seller had to put money back in my paypal acct. so figure out the cost and do it through ebay because paypal is part of ebay.

Dumb Thumbs · Posted: Fri Dec 03, 2010 11:17 am Post subject:

Dan, you are flying WAY too long on the packs, that's why they are craping out on ya. Never take out more then 80% of the mA total cap of the LiPo.

Crashagain · Posted: Sun Dec 05, 2010 5:41 am Post subject:

Look at http://www.hobbypartz.com/
They are on the west coast so you should get your stuff pretty fast.
They have a 2650mah 40C battery for 21 bucks that I use and it works great.
The "C" rating has nothing to do with your battery puffing, as DT stated, and I agree with, your flying to long. Once you start flipping the heli around you start using more juice and need to watch your flight time. I get about 5 minutes and use 70% of my pack with my 450.
What I do and it has never failed me, Set your timer for say 4 minutes, Land and recharge, and look at how many mah's you put back into the pack. If it's a 2500mah pack and you put back 1200mah, then your usage was half. Add another minute to your timer and go fly again. Do this untill you hit about 70%. Then you know how long you can really fly without guessing and ruining batteries.

Trouble · Posted: Sun Dec 05, 2010 12:13 pm Post subject:

Hiya Dan,
Sounds like things are going pretty good for ya in the flying dept., I am totally impressed that you can just jump into a 450 from a SR and can fly all over the place and even do stunts,

I am still on hover Embarassed

, Today was my first day to actually fly after a month and a half off of flying due to a tree growing right in the path of my heli... Shocked

Went thru 4 batteries today, no crashes!!!!!

I guess I just am not a RC heli pilot, but..too bad, I have spent too much money to quit now . I know very little about batteries but I do know that the mah part gives you the amount of time you can fly, more mah, more time flying, The "C" gives you the power. From everything I have read the "avarage" fly time on average batts. is around 7 minutes, some a lil' more, some quite a bit less depending on what they do, I have never heard of anyone doin' 12 minutes flights Shocked

, your batts are prolly cussin' you to their graves, lol. I have set my timer for 6 min. that way I have happy batteries that I won't have to replace for a long time hopefully. All my money has to go for repairs.... Rolling Eyes

Even though today I have no repairs to do....I am at a loss, what do I do now?
Anyway Gratz on your phenominal flying abilities!!!!!!

Crashagain · Posted: Sun Dec 05, 2010 12:30 pm Post subject:

YEAH Trouble!!!!! 4 flights???? Awsome...
You know what I do when I come home with no crashes??
I give my heli's a once over, check the screws, clean them and caress them and tell them how good they did... Tuck them in for the night so they are ready for tomorrow..

Trouble · Posted: Sun Dec 05, 2010 2:03 pm Post subject:

LMAO Crash.....
Yep, 4 whole Batts and no crash, world record for me!!!! Wink

And I am going to do exactly as you say, gonna check 'er over real good and give 'er anything she desires! Too bad it was just hovering, wish I could say I at least flew it in a circle or anything similar.... Embarassed

tombo242 · Posted: Sun Dec 05, 2010 5:52 pm Post subject:

Hey Trouble, you did great.

Don't demean the humble hover, ALL flights must end with either a hover or a crash. If you can't hover you can't land and if you think about it most repairs come from a crash not a successful landing.

I have had 3 "in flight failures" over the last 59 years, one servo and two tails but all other repairs were down to lack of good judgment in some way or other. Keep the hovering going, it keeps the flying time up and the repair time (and costs) down. Just like Crash says "Gives you time for maintenance."

Tom.

Trouble · Posted: Sun Dec 05, 2010 10:34 pm Post subject:

I know you are right Tom, I really should not complain, when I think about it, with these 4 Batts I just flew that gives me a total of just around 50-55 minutes of flight time in all, I know that some guys, they fly all day a few times a week, or even one day, one day would prolly give 'em 5-6 hours, I guess... Question

to be perfectly honest, it kinda gets my goat sometimes, like this guy on youtube, has a buncha vids, his first shows him in a gym hovering his 450 for the 1st time w/o TG, then 2 weeks later he has one where he is doing flips and flyin' all over the dang place Shocked

...how the heck does that happen? the only thing I can think of is ...he has ppl that are pros right there helpin' him out, cuz i'm tellin' ya, it is plenty dang hard to even learn how to lvl the whole head or get the pitch in the main blades, or even learn thr/pitch curves when all you have is the forums to rely on, 'course I have been lucky to have found this Forum with all of you guys on it, but when I read the other forums, man, some ppl don't even get answer..at all, and when they do, sometimes it is a smart-aleck remark by someone who has 4gotten what it is like to be a newb, or someone who doesn't even fly but wants to pretend he does, or an answer by a pro that doesn't realize that the guy prolly doesn't understand a word he is saying and his eyes just glaze over, lol. Not always, I have read some nice and helpful answers also,
but not like here though, I would not even be flying yet if it wasn't for the ppl on here! Very Happy

Agg, another wall of text..drat, oh well, had to vent, had to get it off my chest. Wink

Crashagain · Posted: Tue Dec 07, 2010 9:28 am Post subject:

I hear you Trouble. I went thru that when I was first learning to hover.
I must have had 40 packs thru my heli just starting to get a little at ease about my take off. I go online and read some guys blog about how on his 10th battery pack he was hovering nose in....????.. WHAT????
How is this possible. It's not fair. there are a couple of kids that I fly with that are amazing to watch and I just think, I have been flying RC longer then you have been alive, how come your so good and I still suck!! Life is not fair.
Maybe we need a new sub forum called
" You know what grinds my gears?"
Then we can just log in and vent..LOL

Trouble · Posted: Tue Dec 07, 2010 9:43 am Post subject:

Heh, heh, it be ok Crash Wink

I have a quick temper, but..the good thing is ..it goes almost as fast, I am fine now, I wouldn't trade...mmmm...well...MOST of what I have been through, I still do not know alot...but on the same token I DO know alot, and it has been one helluva ride, Dang near could write a comedy of errors book and make a fortune, hmm, pay for my heli habit...but then I would have to take time away from flyin'....nah, not worth it, lol.

( the one thing I can hope for is that these ppl online saying they can do or have done this or that, maybe they are lyin', one thing about the internet, it allows wannabes to make ppl think they are for real....Know anybody who plays WoW?)

solentlife · Posted: Sat Jan 01, 2011 12:47 am Post subject:

I buy mine of ebay and I got a couple of 2800 mAH LiPos ... 3S, 30C... for approx $20 the pair ...

The weight is slightly less than the standard 2280 mAH that is recc'd for 450's .. and has greater capacity.

Battery brand label says :

RC ModelPart

Basically all my gear comes via online as Latvia is very poorly served for RC gear as there are very few pilots here ... total population of Latvia is 2.2 million people ....