wake133

I have a Exceed j3 cub. I want to upgrade it to brushless so i can fly it with out using full throttle for the entire flight and i want it to have power enough power to do whatever i want. This is what I'm thinking of putting in it from an exceed Alpha 400 (920kv) brushless motor, 30A Electronic Brushless ESC Speed Controller [Volcano Series],Capacity:1750mAh Constant discharge: 20C Burst rate: 30C (15sec) Configuration : 3S 11.1v Pack size: 93x33x22mm Weight : 155g lipo battery. I know I will have to modify the plane to make the motor and battery to fit, but will the motor esc and battery configuration go together well? What prop should I go with for this set up? Let me know I want to get this stuff on order asap.

eccvets

I think in the end, you have to use a watts meter to check if your prop size is ok for your esc/motor/battery combo. Even if someone uses the same exact setup as the one you are thinking of does not gaurentee that the amps the motor will be using with that prop will be the same. I highly suggest either making your own or buying one. I oped to buy one cuz I dont have the time or patients to build/make my own and with a bought one like from wattsup meter, you can see 3 or 4 settings at the same time continously running all at the same time which gives you a lot better idea whats going on with your system.

How heavy is your plane? the stock mabuchi motor (I'm assuming its a 7.2v version) puts out about 2220 kv which is a lot more then the alpha 400 (920kv) brushless motor although it is probaly more efficient. Are you planning on using a prop which is a lot bigger?

I have been personnaly looking at the 2212-6 motor from suppo AKA the grayson hobby (ParkJet Combo) 2212-06 V2 (Super-Sonic) Brushless Combo [SuperSonic C] http://www.graysonhobby.com/catalog/...roducts_id=414 Although I have found it on ebay for 20 bucks for the motor and 30amp esc which is half the price as grayson. IDK how Grayson has upgraded theirs (I heard theirs are special) but idk whats so good about them. With a 6X4 prop with it, it seems to keep the amps below 30 and puts out 24 oz (perhaps more) of thrust for a pusher jet using a 3S Lipo. Takes about 2weeks or so to ship from China/Hong Kong though but the shipping is free.

What made you pick the Alpha 400 (920kv) brushless motor in the first place?

You can try a GraysonHobby Super MegaJet V2 & GH 50A ESC wtih 3Amp Ext BEC
[SuperMega -] http://www.graysonhobby.com/catalog/...roducts_id=645 . I'm pretty sure your piper cub will fly pretty quick with this motor and the below props... In fact the wings might rip off with all that thrust

Prop	Voltage	Current	Watts	Pitch Speed	RPM	Thrust (oz)
6 x 4 APC	11.1V	28A	316W	79.2 MPH	20910	32 oz
6 x 4 APC	14.8V	37A	491W	88 MPH	22110	38 oz

wake133

Thanks, Yeah from my recent research I seem to get the same answer, (get a meter) so I think thats what ill do. I was told by a guy at my local hobby shop to get a 450 870kv for the cub and he said that thinking I had a bigger cub than I do The Exceed j3 cub is a 1/5 smaller than the one he thought i had. When I told him how big mine was compared to that he said the 450 might be too much for it. So on nitroplanes i looked at motors and the 400 920kv was the next closest one, the others were sold out. I figured that it was worth a try being so cheap with great reviews. I also went with the 30amp esc. If this wont work on this plane I might just try and build a plane with all my spare parts laying around.

eccvets

one thing which is worth doing is trying to figure out how much thrust you might expect given a motor/esc/battery/prop combo on various rc forums or a website like this one http://www.flybrushless.com/search.


BTW: Ithink its always better to have more power then less, you don't need to use all of it all the time and its a lot easier on your equiptment when you dont gotta go full throttle the entire time. Plus you get longer flight times.

wake133

I think I will have enough power and then some. if not I can always upgrade