jmir

My Feedback: (1)

I'm using an E-flite 450 motor with my E-flite Tribune FX with a 25 amp ESC and TP 2100 mah batteries.

The E-flite 450 specs call for props up to 12 X 6 E. Using that prop, the motor and battery get very hot, to the point that I think I have ruined one of my li-po batteries because of the overheating.

I no longer use the 12 X 6 prop, however, I have similar problems with the following props:

12 X 3.8 -- at full throttle, wattmeter shows 218W which exceeds the 175W limit for the E-flite 450.

11 X 4.7 -- at full throttle, wattmeter shows 210W which also exceeds the 175W limit.

I have used the E-flite 450 motor with my E-flite Mini Ultra Stick, using a 10 X 3.8 prop and never had any motor/battery overheating problems. However, I think the 10 X 3.8 prop would be too small for my E-flite Tribune FX, although I have yet to try that.

Any suggestions?

jmir

My Feedback: (1)

I just read in the specs for this motor that it can take up to a 10 X 3.8 (slow flyer prop) or up to a 12 X 6 (electric prop)

How can you tell the difference between a slow flyer prop and a prop for electrics? Any experts out there?

Slo-V Flyer

Those types of props are more specifically designed by APC. An APC "Slow Flyer" will have a broader end, an APC "Electric" or "E" prop will be slightly narrow at the tips. I can't remember which one is more angled at the center, but one is more angled (pitched) at the center and one is more flatter at the center. The packing for these props usually as it marked as SF or E. From what I understand, E props are designed for speed, while SF props give more thrust and lesser speed.

I've used that Park 450 outrunner, and I wouldn't recommend over 10 or 11" prop with 3 cell lipo. that 12x6 is probably for using a 2-cell where the lower voltage requires a larger prop to get power (it draws more amps to get the watts). Also, instead of looking at wattage, look at how many AMPS the motor is pulling from your setup to make sure you don't over stress and heat your battery, motor and ESC. That motor is rated for I think 14-16 amps at maximum throttle. You should be no higher than that amp draw whether using a 2-cell or 3-cell lipo, so go down in pitch or prop size to correct the issue.

The TP 2100 battery I understand is rated for 30 amps continuous, so you must have really pulled some amps outta that thing with that motor and 12 inch prop for it to go bad. Remember Watts = Volts x Amps. I think the instructions meant that you should use a 12x6 prop for 2-cell lipo operation (which according to my numbers means 16 amps x 7.4v = 118.4 watts), and something smaller for 3-cell setup (again should at most be at 16 amps x 11.1 v = 177.6 watts). Key is to not draw more amps than the lowest limit of any of the components in your system, motor (14-16 amps in this case), ESC (25 amps?) or battery (30 amps?), you would want to prop your motor to draw no more than 16 amps in this case, since it has the lowest capability to handle amps.

Good luck.

airraptor

My Feedback: (66)

i use a 12x6 apc E prop on mine all the time with common sense batts with no problems at all. does your esc auto program?

i use the eflight 20 amp speed control on mine i will go and do a quick amp pull with the 12x6 to see if your close to mine. i will re post in 10 minutes

airraptor

My Feedback: (66)

well i tested mine on the tribute with 12x6E and got 217-220 watts at 11.5 - 11.6 volts

i fly the tribute with a 11x4.7Sf - 4.8 with a 3s1p 1100 dont know why your over heating but maybe your fly at WOT for to long. if so then you need to get a bigger batt and run the 11x5.5E prop or the 10x4.7 SF prop i have flown it with the 450 and the 480. the 480 and 2100 for windy days just to have extra planes at the field because with the 480 and 2100 is just to heavy for low and slow 3D stuff

jmir

My Feedback: (1)

Thanks for all the information. It is all very helpful.

I looked at the specs shown by atlantahobby.com and I am definetely working the motor/battery way too hard. It shows I the maximum prop to use would be a 10 X 3.8 Slow Flyer.

I checked the amps on the 11 X 4.7 and at full throttle is 18.8 amps. Way too much! I guess I will be ordering some 11 X 3.8 today.

Thanks again!

Jmir

jmir

My Feedback: (1)

I meant to say I will be ordering some 10 X 3.8 today, not 11 X 3.8.

Slo-V Flyer

Hmm... 18 amps should not mess up that Thunder Power 2100mah 15C battery, unless I'm wrong and your's is lower than 15C discharge rate? Well anyway, good thing you checked the amp draw, because your motor would have died eventually.

Slo-V Flyer

Airraptor how many amps are you drawing with that 450 motor at 200+ watts? Definitely a lot more than 16 amps I'm sure. None of my business, but for your motor's sake you may want to prop it down from the 12x6 and stay within it's rated amp range. And don't think that by using lower throttle you wil be ok. Because of the way ESCs pulse width modulation throttle system works, your motor always receives "full" voltage from your ESC and therefore for that fraction of a second pulls the full amperate, meaning over the long run you will end up with a bad motor and possible battery if the battery isn't rated to handle more amps.

So basically to beat a dead horse, you should prop your motor to draw the maximum it can handle at 100% throttle. Don't prop it to draw more amps than run it at lower throttle. Someone else posted this exact information with more technical detail, but I can't remember who.

Good luck!

balsadustmaker

OK...what would happen if you 'underprop' the 450.....say prop it with a 8x6 and a TP2100? I know the amps would be less, but would you hurt the 450 or just have a lousy flying plane?

patnchris

Are you testing on a bench, static....If so you will pull a bunch of watts. A bench test is really not a good indicator as to how a motor/ESC/battery combo will work, in the air. My Mini Ultra Stik will toast an ESC and have the motor smoking, in less than a few minutes with a 10X7....However, in the air, things just bearly get warm, even when I fly it really hard. While I agree that a 12X6 is way too much prop for the E-Flight Park 450, an 11X4.7 should be fine. A lot depends on how large and how much drag the plane has, but I have 5 Park 450's in different planes, and have never had a problem using 20 amp E-Flight ESC's and Thunderpower 3s2100ma batts. The only time I've cooked one was when I did a bench test to see how many watts I could pull with an 11X4.7.....But the same combo in a plane, in the air has given me many trouble free flights....JMHO...Pat

Slo-V Flyer

Because of the inherently lower rpms outrunner motors like the Park 450 work at, it should not hurt the motor at all to run it with a smaller prop. Just make sure whatever prop you use, at full throttle it should not pull more than the motor's rated amps, in this case 16 amps.

So yes you can use a smaller prop, and as a result you will *possibly,* depending on the plane, get crummy performance.

dalelvn

I fly my 450 on a 10X8 slo fly (gws) on a nitro planes ultimate with a 20 amp e-flite esc and have No heat issues and on a fresh pack can hover that 28 oz plane tribute is much lighter than that so that set up should work fine

dabvid

hey guys,
im going to be using the park 450 in my new multiplex minmag( with the permax it is slower and less climb than a slug) i have a 1700mah 20-30c lipo3 cell and im getting a 25amp esc what prop should i use on the park 450, i was thinking either a 10x6e prop or a 10x4.9-3.8 slowflyer prop. all help appreciated.
regards,
dave

Slo-V Flyer

WOW! Hover a 28 oz? That means you're probably in the neighborhood of about 250-300 watts!! Jeez man, even on 3s lipo the 20 amp speed controller will only handle so much current.... never mind the motor which your lucky is still lasting. But I've heard of worse things. You'd have to be pulling over 23-25amps to get that much power from 3s lipo...

Again I will let you know that running at low throttle will NOT help things in the case. Every single pulse of power that the ESC sends to the motor at lower throttle settings still gives out full voltage and pulls maximum amps for that fraction of a second, except it does that thousands of times per second depending on the PWM frequency of the ESC. The only reason a watt meter displays lower amp draw at low throttle when you hook it up between your battery and ESC is because it is averaging out the power it sees and then displays it. So in reality if your battery/motor/ESC is not rated to handle the MAXIMUM current you pull at 100% throttle, you will eventually risk burning up something (hopefully not your fire-happy Lipo).