tylerman

Let me start off by saying that I am fairly new to electrics, and I need to know some info from people that are experienced with the right combination of things.

First off- this is what I am flying right now---
Jeti 8 amp. ESC
Thunder power 3s. 730 mAH.
AXI 2208/34 brushless motor
APC 10x3.8
With this setup I am flying a Tensor 4D.

Here are a few of my questions:
This set-up seems to work fine, but I dont really know what fine is--
Is there a better prop selection for this combination of gear?
I want to make sure that I am not overloading my gear with too much prop-
If I move to a smaller diameter prop. and less pitch(or more pitch?) Is it possible to in a way over-rev my motor?

I know that there are formula's to calculate these kinds of things--
If anybody knows of such a formula-please share.

I just want to get the most out of my model without bad consequences-
Thanx

Matt Kirsch

My Feedback: (21)

Fine is if the plane flies the way you want it to fly, responds the way you want it to respond... Right now, you can tell if you're overloading your gear at the end of a flight. If the gear is uncomfortably hot, you're pushing it too hard. A little warm is okay. Cool as a cucumber is great.

With AXi motors, you can go to their website, and look up your motor in their products section. Each of their motors has an application table showing typical battery/prop combinations. If you can't find yours, you can extrapolate from the existing data and get a rough idea of how your setup is working.

Reducing the prop diameter or pitch will reduce load on the motor, and reduce the amount of power you have in flight. That might not be the ideal situation, if you're not pushing the system now.

tylerman

I want to experiment with how my plane performs with different pitches and diameters without hurting my gear.

Matt Kirsch

My Feedback: (21)

The best thing for that is an Astro Whattmeter or similar device. Being able to actually measure the effects of a prop size change on the power system is by far the most accurate way to make sure you're not going to overload the setup.

You can develop a "feel" for how a certain prop size change will affect the current draw too. Things like, "An inch bigger prop will draw a little more current. I'm at 12A now, and everything can handle 20A, so a measly inch can't possibly put me over the top."

tylerman

I have no idea how many amps I am pulling with my gear--Maybe I should look into one of those toys.

theHarpmanDan

hello tyler,


I ran the numbers for your settup...MOtocalc claims you are drawing 10 amps, 16.7 oz. thrust. You do Not want a bigger prop with that speed controller!

try a 9x4.7 ...the added prop speed will help the climb rate. Although for that plane, you probly allready have unlimimited vertical? They look fun. What is the all up weight? I am curious abouth your Power to Weight ratio.

theharpmandan

If you need more numbers, just ask.

Or just use Motocalc, or similar.