AXI 2808/24 - what prop for 3D?

[bigbrain]

I have mounted AXI 2808/24 in my Micro Show Flyer Graupner
https://shop.graupner.de/webuerp/servlet/AI?ARTN=9551

What prop do you suggest me for 3D?

Thank you

[Spaz]

i run the 11x5.5E APC with polyqest 20c 1800mAh 11.1v i get 30amps.
it is propably the most prop you can run, make sure to have good cooling holes (air-in and exit) and use the throttle carefully

[bigbrain]

That plane is my first electric.

Should I give it any degrees down and right?

Thank you

[Diablo2006]

about 3 degrees down, 5 degrees right

[bigbrain]

	Quote: Originally Posted by Diablo2006
	about 3 degrees down, 5 degrees right

Are you sure 3 degrees down and 5 degrees right work well?

Thank you

[Diablo2006]

I had this motor on a large shock and it flew as straight as an arrow on all throttle settings.

Obviously, this changes with prop size (i had a 8X3.4) and aircraft weight and design

[bigbrain]

I have a LIPO battery 3 cell 2100 10C and another 3 cell 2100 18C.

Which time of charge and how many Ampere should I give to the two batteries?

Thank you

[Uncle Brett]

Charge each battery at no more than 2.1 amps untill done.

[bigbrain]

Is this a good charger for lipo batteries?

http://www2.towerhobbies.com/cgi-bin...&I=LXKAU0&P=ML

Thank you

[Uncle Brett]

The PolyCharge 4 works great for small batteries up to 3000mAh. I think for the money, it's tough to beat. There are a few drawbacks to it compared to some single battery chargers in this price range. It doesn't have a digital readout that gives you charging info and it doesn't charge to the battery's full capacity (98-99%). But hey, being able to charge 4 batteries at once on a single $100 charger is well worth not being able to see how many mAh you're putting into the battery IMO. I have 5 chargers; 2 Tritons, a Schulze, a TP 1010C and the PolyCharge 4, and without a doubt the PolyCharge gets the most workout.

[bigbrain]

Do you use lipo balancer like this?
http://www2.towerhobbies.com/cgi-bin...?&I=LXMGS7&P=7

Is it really important to use balancer?

Thank you

[bigbrain]

Perhaps who sells balancers says they are important and instead they aren't.
What do you think about?

Thank you

[Uncle Brett]

Balanced cells in lipos are very important for the longevity of the battery. Here is an explanation by BEC on RC Groups that I have copied without his permission, I don't think he'll mind.
Balancing your LiPolys – why??


Well, as we all know by now (or should, if we’re using them), lithium batteries are much less forgiving than nickel types when they’re operated outside of a certain voltage range. Also, when they ARE operated outside that range, bad things happen. If you’re lucky, all you do is shorten the life of the battery. But either ruining the battery itself or even those much-discussed fires are possible results of going outside each cell’s voltage limits.
But we don’t, except for our Aero Aces and other very small models (and in our cellular phones), use these cells individually. Instead we typically use them in series of anywhere from two to four, or even ten or twelve cells. So, unless the cells in the battery are perfectly matched for voltage and capacity when the battery is built and they stay that way, as long as we both charge and discharge them as a whole battery (and not individually), there is a danger that sooner or later individual cells will be driven outside their safe voltage range even if the pack, as a whole, stays within it.
It has been my experience in about three years of lithium-polymer battery use that quality packs, when used well within their rated limits (especially for discharge rates), will start out balanced and tend to stay that way. From that one could conclude that I don’t really need to worry about pack balance and that I don’t need any devices that are designed to help me balance my packs.
But things are changing now. First of all, cells are available which can deliver much higher currents, both in absolute terms and in terms of multiples of their rated capacity (so-called “C” ratings). Packs made from these cells seem to tend to drift further out of balance while being used within these higher stated limits than the older lower-current types. Second, there are less-expensive cells and packs available now, and these also seem to be a bit less consistent or vary more in capacity from cell to cell within a given battery pack. Both of these situations can set up the conditions for individual cells being driven to too high a voltage when a pack is charged with an ordinary series charger.
Regardless the type of cells you are using, to be safe, it is best to periodically check the voltages of the individual cells. This is best done when the packs are charged or nearly charged. If, when checked, the packs are out of balance, you need to do whatever is necessary to bring them to the point where they match closely (within a couple of hundredths of a volt, hopefully).



I hope this explains to you why it's important to keep the battery balanced. You don't have to balance with every charge, about every 8-10 cycles on the battery will do the trick.