3d nate

My Feedback: (12)

Hello everyone,

I know you all are E-power experts. I have a question on powering a larger model. My father and I are manufacturing some new 3D biplanes (3dbiplanes.com). We are making two sizes and I want to know if I can E-power them.

I am wanting to convert the smaller one for price reasons. I have been looking at a few options and I like the AXI 4130-16? Will this work on our plane? My big question is what Li-po do I need? Do I have to go with a 8 cell or can I use a 5 cell? What size (mah) 4000? How do I figure the amps? I am new to this e-stuff. We want hover power but also to keep it as light as possible.

The specs on the smaller plane are 6.5 lds. 900 sq. 44" wing. We are using the Saito 82 for power now. I would like to keep the weight the same as it is now if possible. The Engine, tank w-fuel, thr. servo weigh about 31 oz. wet.

Please let me know if you have any ideas.

Thanks,
Nate
3D Biplanes.com

luc-RCU

6.5lb is light for the 4130/16, I would go for a 4120 and 5S 2000 is fine
I use the 4130/16 on 8lbs planes (H9 AT66, P-51 miss america and WM spit)

Greg Covey

I think the key issues here are 3D and biplane which means you'll want much more power than usually seen in a scale warbird. For good 3D power level, use 150w-200w/lb. This means that with your AUW of 6.5lbs, multiply it by 100-150 to get 650w-975w which is right in the operating range of the AXI 4130 motor.

The choice of an AXI 4130/16 is quite reasonable then for the power level needed. I would use a 6-cell configuration (typically made from two 3-cell packs in series) and a 15x8 or 16x8 APC e-prop.

Matt Kirsch

My Feedback: (21)

Good 3D definitely needs 150 Watts per pound, minimum, and with AXis, the whole thing is easy:

1. Multiply the anticipated weight by 150.
2. Look up AXi motors at www.modelmotors.cz that can handle that many INPUT Watts.
3. For 3D, look for the motor that can spin the biggest prop on that number of Watts.
4. Take the battery, motor and prop size right off the chart and bolt it right to the nose of your plane.

Tweet

My Feedback: (1)

Matt,

I don't see on the Model Motors web site where it gives the value in watts directly. If gives the max current in a max current/seconds format. I always find I have to play around with various configurations of batteries, motors, and props to actually what input watts I will get to get to see if I am getting the 100 watts/pound or the 150/watts per pound of whatever I am looking for.

Am I missing a table on the Model Motors web site? It just seems like there are a few extra steps, either that or I'm missing something (always a possibility).

3d nate

My Feedback: (12)

Thanks to all for the info. It looks as if I am on the right track. I guess it will depend on batteries and props to fine tune the setup.

Are the Jeti controllers worth paying more for, or will the Phoenix 60? work OK?

Thanks,
Nate
3D Biplanes.com

jbflier

Hi tweet; I too am confused about this imput watts thing.......I converted a Funtana 40 and am using an AXI 4120/12 in it with (2) 3s2p 4200mAh batteries only because of what I've read others are doing. I'm looking at my motor manual and see nothing even close to 750-900 watts mentioned. My Funtana flies great, but I'd like to understand what I'm doing on my own.

Matt; Is there another way to figure this out, that I'm missing?

Thanks in advance..............

jbflier

Hi tweet; I too am confused about this imput watts thing.......I converted a Funtana 40 and am using an AXI 4120/12 in it with (2) 3s2p 4200mAh batteries only because of what I've read others are doing. I'm looking at my motor manual and see nothing even close to 750-900 watts mentioned. My Funtana flies great, but I'd like to understand what I'm doing on my own.

Matt; Is there another way to figure this out, that I'm missing?

Thanks in advance..............

Joacim

The Jeti controllers are much better than the Phoenix in my opinion. Axi motors are good for there price, but for maximum performance the Actro and Plettenberg outrunners are better, lighter, higher% and better quality! for this plane maby the new Orbit 30 or Actro 24-6 or 32-5 would work.

jbflier

I just went to the Actro page on Hobby Lobby's site and they do use output watts for their motors. That's nice if this is how we are to determine motor sizes, etc for or planes......

Greg Covey

Spoken like a true Swede, Joacim!

The Jeti controllers work great with the AXI motors and the new Advance PLUS line is the easiest controller in the industry to program.

As for watts in vs. watts out, you can only measure watts in with a wattmeter so forget about about using watts out. Unless you are pushing the motor limits, simply multiply watts in by .9 to get watts out.

Joacim

Yes i am a Viking

Actro Köhler always spec there motors in output watts, and eff% including controller and conections. Best way for us to calulate performance on a plane is INput watts, so on a good outrunner or DD motor i have these rules 300watt/kg for powerfull aerobatic, 350-400/kg 3D, all above is extreme


For 3D a big prop is good!

Here are some test data i have made on some Actro motors, soon also the 24-3 and 40-5 will be aded.
http://web.telia.com/~u15807174/TestmotorerActro.htm

Greg Covey

Don't get me wrong, I love the quality of the Actro Köhler motors. Here in the states, the AXI motors win the cost battle. In this thread, the vendor specifically stated he was looking at converting the smaller bipe "for price reasons".

Joacim

Yes, for its cost the Axi motors are very good, and the performance is often enough, but if one like even better motors and are willing to pay some more the Plettenberg or Actro outrunners are a better option, also some of the Torcman and Flywere motors are very good and has some nice torq for big 3D props.