Ok, like most of you I get tired of the short flight times, even with my lipo (GP 910) it seems too short. I have two of the GP 910s and I keep them both charged so when one runs out I can just swap them, but I was wondering if I could use them both at the same time to double my flight time. I got to looking around and found this site (from an RCU ad no doubt)
http://www.smart-fly.com/Products/BatShare/batshare.htm
Scroll down to the "BatShareUltra"
I know it seems silly, but I am thinking about trying it out, the weight of two lipos shouldnt be that much extra, heck I bet it weighs less than the stock pack. I am thinking I could strap one underneath where the stock pack goes.

You can run 2 batteries of equal voltage and Mah in parallel. Matter of fact, thats what a 3s2p battery is. 2p = 2 parallel. Weight might kill your flight time, but it is possible and lots of folks run them in all kinds of applications.

Just make yourself a Y connector and you're good to go.

Michael

yeah, you probably will be ok as far as the weight, although you will loose some performance. I wouldn't worry about that battshare thing though, it's $30 bucks for something you wont need. Basically it switches the load if one of the batteries fails in a short open-short or whatever else. You just want a parallel wiring harness like Michael was sayin =)

Good luck

Ok, I just bought this
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNKY8

I was going to make my own, but it was just as cheap to buy that. I'll keep everyone updated on how the AXE flys with 2 lipo packs. This should give me 1820mah

Well I just did a test flight with two batterys attached to the AXE to see how she would handle. IT WAS BETTER! I couldnt belive it, the AXE flew better with the extra weight. I had to add a flew clicks of right cyclic because it wanted to drift left for somereaon but that was all. It flew so much better in fact that I decided to attemt nose in hovering in my garage, somthing I hadnt done before, it was fine. I cant wait until I get that adapter now so I can see what kind of flight time I get from two packs.

Kenny,

Please let us know how it goes when you wire in the two lipo batteries. Does it improve performance/flying time?

Ted

Kenny,
I noticed in the pics your posted that your heat-sink is covering the vent holes on your OEM main motor. You ARE gonna want to remove your motor, unsnap the HS, and look inside the HS, you'll see the heat/carbon dust marks on the inside with the thin film of HS compound.
Use a hacksaw, file &/or Dremel tool and remove the HS material that covers the vents on the motor. This will SAVE your motor from a meltdown, (although the effect at 30' is pretty cool). Be SURE to add more "HS compound" (Radio Shack #276-1372A, silicone based) to the inside of the HS, BEFORE snapping it back on (a little goes a long way). Wipe off excess that oozes out, or you'll have white stuff everywhere!
You may want to do this before you HOT wire in 2 Lipo's, to your "10 pounds of --it, in a 1 pound can, flying machine!"

Rick

yeah, I would second what shadow said. sounds like you've got it all figured out and are on your way =) Good luck =)

you may want to just monitor the motor temps with the extra weight on there and see how it does.

You can snap the heat sink off without removing the motor to cut the notch - that's the first mod I did when I got mine back!

I just notched my heat sink out this morning and it's running much much cooler. I need to swing by radio shack for the heat lube stuff.

PS. By the way, I got my lil guy back last night. I'm back to comming in an hour early and staying an hour late to get some fly time in.

You go, Ted! At least when we refer to our "lil guy" in here we all know which "lil guy" we're referring to! (I hope!)

Bet your wife likes that

Well I didnt get my order in from Tower today like I was hopping too, but I did some prep work to get the AXE ready for her two pack flight. You guys were right about the heatsink, easy mod with a dremel cutting wheel. Didnt even have to take the motor off, just poped the heatsink off and went at it.
Maybe the mail man will make me happy tomorrow

Looks Good Kenny! Your motor will be much, much happier now!

Did you remember to add more HS compound, to the Heat-Sink before snapping it back on? Without it, the motor could still get hot spots, cause the HS doesn't fit perfectly against the motor-can, so the compound fill in the gaps so the heat can be pulled away.

Rick

Mike,

The wife is in Baltimore for the next three weeks. It's just me, two kids, three dogs, three cats and one fish. The second fish died last weekend.

I have been building my new aquarium stand the last couple of nights, so I'm not staying as late as I used to. Also, I have three lipo packs. When one pack is done, I put it on the charger and grab another pack. This week I've averaged 5 flights per day. I love my life!

By the way, I'm placing an order for my RC Tek 450 tomorrow unless I talk myself out of it. I'll get the radio, servo and batteries later. I got a killer deal that I can't pass up.

Ted

So I got my adapter today and was so excited to give this a try that I stayed up to 1am. Well first off, I think you need a Phd in Electronics to solder a Deans connnector correctly. Good God someone please tell me the magic words that most be recited prior to putting that thing on. I could not get the solder to stick to the gold part of the connector at all. I had to solder it 3 times before I finally got it on there nice and tight. So with all that behind me I finally got both Lipos hooked up and started off nice and easy, just hovering in my garage. The Axe flew great with the weight of both packs and I still maintain that it flys better, I dont know why it just seems more balanced. I was keeping an eye on the clock so I could report back to you guys about the increase.... well about 10 min into the flight I start looseing power... I am like this cant be right... so I sit her down and all of a sudden I see fire! I quickly checked to see if it was one of the lipos (Luckly it wasnt) it was the ESC, so I yanked both batterys out as quick as I could. I had bought a fire extenisher a few nights ago but luckly I didnt need it either, as soon as I unhooked the batterys it wasnt a problem....now my whole garage has that sweet smell of fried circuit board.... In a way I wished it would have fried the RX because I just bought a new one of those and could have replaced it.... instead I am grounded until I get a new ESC... I was looking for a reason to upgrade to a gyro anyway so I guess my next Tower order will be for two ESC and a Gyro.
Long story short, I dont recomend trying two batterys at least not on the stock ESC, although I dont understand what the problem was because it should have not been pulling any more amps then normal.

PS. Sorry about all the typos, its late...I tried to edit the ones I could find
PPS. Just checked tower to see what the stock 3-1 was going for.... $85 freaking dollars, dont know what crack they are smoking. I dont plan to use the stock one anyway, I just wanted to see if it said what AMP it was...and it doenst. I am thinking 25 amp ElectriFly for the main... sound about right?

Kenny,

Man I'm so sorry to hear about your luck. If I remember my electronics training right, batteries hooked in series increase the amps, batteries hooked paralel increase volts. Either way, something cooked the 3in1.
Hope your able to get up and running asap.

Ted

man, that sucks =(

yeah, if you are running them in parallel then you should be good, if you were running them in series, I wouldn't think that you would even get 10 min out of them. I bet the extra weight might have done it to ya, just because the motor has to draw more amps to maintain the hover with a heavier weight load. No idea what the stock ESC is rated at, but I imagine that it isn't rated over 20A with a heatsink, which it doesn't have, probably much over about 12 to 15 would toast it. If the batts were completely dead when you finished, the max average you could have drawn is 10.92A.

anyways, yeah I would say 25 is probably a good size. CC makes a better esc than electrifly, but costs a good deal more. If it's not worth it to ya, then go with the cheaper one. I usually size an ESC just over what the max amp draw for the motor is. In a 370 for example the resistance of the stock motor as measured from one commuator lead to the other is 0.6 ohms, so if you take 12v and divide that by 0.6 ohms, you get a max current draw of 20A, so a 25A ESC could take the full brunt of the motor in a stall. Not sure where the 380 rates though.

Sorry about your bad luck =( on the upside, you get to get all new parts that are half way decent instead of the stock stuff

mrasmm, I bet you are right about the weight making the stock motor draw more amps. The thing is I had just got done reading on RCU about installing a fuse between the ESC and motor... I should have done it...it would have saved me in this case... You can bet I will be putting a fuse on the new one

Well, you didn't Batteries hooked in parallel increase AMPS - batteries hooked in series increase VOLTS (you know, sums!!)

Anyone tried installing a heatsink on the ESC???

Sorry about your meltdown Kenny.
Normally battery packs wired in paralell increase amperage, voltage stays the same, so if you took your 2 910mah batteries would give you 1820mah 11.1v pack. Wired in series would increase voltage but the amperage stays the same, so you would have a 22.2v 910mah pack, that would give the stock ESC about 20 seconds or less til it was toast.
I almost sure the stock ESC for the main is rated at 12 amps & the tail 4amps. Hooked up to an ampmeter the main motor draws between 9-11 amps at full load, be sure to clamp heli down before testing! Tail motor drew 3.6 amps at full load. As I've spoken about in other posts, fuse protection to the motors in a must for protecting the stock ESC from meltdown. It's also good to have on purpose built ESC's as well, better a 50 cent fuse than a $30 dollar ESC.

Rick

=) yeah unfortunately hind sight is 20/20. If you get an ESC with current limiting then you wont need a fuse because the ESC will not put out more amps than it is rated for. That can be quite a handy feature sometimes and save you some dough =)

Hey Mike,

That's why I'm not in Crypto Electronics anymore. I couldn't get past the color bands on the resistors.
Thanks for bustin my chops and settin me straight.[>:] LOL!

By the way, my "new heli" should be delivered on Wed. I'm pretty fired up (in a good way).

Ted

Looking at your photos, if that thing ever goes up in flames, it's going to be something! So much for guessing. I wrote this coment before reading the rest of it as it did blow eh?

Cool, Strat - let us know how it flies!!