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Old Nov 01, 2012, 02:14 AM
More coffee, please!
sir_clive's Avatar
Austria, Wien, Vienna
Joined Jul 2011
658 Posts
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Originally Posted by ajbaker View Post
I agree with all of the above. But, there is one thing that I have never worked out. When you use brake, there is less overall drag. That is the easy part. There is a cost in amps(milli) to hold the prop from spinning. Therefore, if I set the brake on, will there be more or less flying time compared to the prop that is freewheeling in the wind with no current draw (technically, the motor becomes a generator-disregard for this perponderance)? The drag is greater and the plane will not glide as far. I am sure some tech head has the exact answer for this one. Hmmmm...
AJ
As far as I know, the brake does not use any battery power. Brake on setting only shorts two of the three motor wires, which leads to electromagnetic force oposed to the direction in which the prop would freely spin. In other words, the motor becomes a generator and the current generated stops it from spinning. If you try to spin the prop by hand, you won't notice a difference between brake on and brake off, it takes quite some spinning speed to generate enough current to oppose the spin in a noticeable way.

Brake force is enough to fold the prop, but it's nowhere nearly strong enough to "block" the prop (as a car brake would do).

On my other plane with a folding prop, the prop does not fold if brake is set to off.
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Old Nov 01, 2012, 02:41 AM
Argue for your limitations
ajbaker's Avatar
Lincoln, CA
Joined Oct 2006
8,422 Posts
Quote:
Originally Posted by sir_clive View Post
As far as I know, the brake does not use any battery power. Brake on setting only shorts two of the three motor wires, which leads to electromagnetic force oposed to the direction in which the prop would freely spin. In other words, the motor becomes a generator and the current generated stops it from spinning. If you try to spin the prop by hand, you won't notice a difference between brake on and brake off, it takes quite some spinning speed to generate enough current to oppose the spin in a noticeable way.

Brake force is enough to fold the prop, but it's nowhere nearly strong enough to "block" the prop (as a car brake would do).

On my other plane with a folding prop, the prop does not fold if brake is set to off.
IIRC, I did notice more holding force when the brake was set on another plane. I will put together a couple of setups and measure "brake on" / "brake off" current and see if there is any difference. Sounds like "wax on"/ "wax off" huh?

On my Radian, it does not matter whether the brake is on or off. The prop will fold back and stop spinning.
AJ
Update: It would seem that both of our perspectives are eminently correct. Read this: http://www.rccrawler.com/forum/elect...principle.html
It sure cleared up what is going on for me. Especially the soft, medium, and hard brake settings.
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Old Nov 01, 2012, 02:52 AM
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JLT_GTI's Avatar
Oviedo
Joined Jun 2010
2,322 Posts
Quote:
Originally Posted by ajbaker View Post
On a pusher, I can see that. On my Radian, the blades fold whether I have the brake on or not. But, maybe that is just because of the Park motor that it comes with. I don't have enough test samples to make an "in general" conclusion.
AJ
On my Phoenix 2000 the first day i forgot to enable the brake and when you usd the motor, the propeller kept spinning in the air despite being a folder prop and i had to actually slow it down quite a lot (by climbing with no power) to stop it
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Old Nov 01, 2012, 05:59 AM
More coffee, please!
sir_clive's Avatar
Austria, Wien, Vienna
Joined Jul 2011
658 Posts
same here, it just went on spinning. I guess it will also depend on the motor (some spin easier than others when no throttle is applied)

the last time on slope, I had a few WOT climbs, the rest was just thermals. After 45 minutes in air, I still had 88% of my 1600 mah battery full, which was hillarious. so if the brake on setting does draw battery, it would be minimal. but a measurement would be a very interesting experiment to prove it one way or another. at least for the given ESC.
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Old Nov 01, 2012, 07:21 AM
Just thumbing through...
victapilot's Avatar
United States, SC, Simpsonville
Joined Feb 2009
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It probably does depend on the setup. My sailplanes have big props, 14x10 on my Bird of Time, no way will it stop spinning without brake. I also use brake on a hotliner and a Shrike with fixed props to prevent prop spinning and breaking on landing. For my AXN with inrunner, brake is not as effective as with outrunners.

I guess someone could test with a wattmeter and a big fan in front of the plane??
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Old Nov 01, 2012, 08:50 PM
BGR
Foam Junkie
United States, CA, Oceanside
Joined Dec 2003
1,656 Posts
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Originally Posted by Beanz View Post
Oh- by the way, I've just ordered my THIRD AXN. My first one's a bit tatty now after it went in hard whilst I was teaching my mrs to fly (or crash, really) and my second ones the one I shoved an overpowered motor in. That one flies fast now but is a bit of a handful at the moment but I'm sure when I can get some decent time to spare, I'll iron out it's faults.

The third one's because my mrs wanted to buy me a present. I spent ages looking at all sorts of planes before going back to the good old AXN because I know I'll still have this plane for years to come (as opposed to some of the slightly more risky planes I was drooling over). Nothing worse than wrecking a plane that came as a present.
I just got my second AXN in the mail today. I too looked for something else but went for another AXN.
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Old Nov 01, 2012, 11:52 PM
Argue for your limitations
ajbaker's Avatar
Lincoln, CA
Joined Oct 2006
8,422 Posts
Choices

Quote:
Originally Posted by BGR View Post
I just got my second AXN in the mail today. I too looked for something else but went for another AXN.
Yeah. Got it. You are the type of guy that if you had a chance to go for a new woman, you would choose the same one....
AJ
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Old Nov 02, 2012, 06:18 AM
RC Airplane (Recently Crashed)
mutha's Avatar
Australia, VIC, Melbourne
Joined Jan 2011
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Originally Posted by ajbaker View Post
Yeah. Got it. You are the type of guy that if you had a chance to go for a new woman, you would choose the same one....
AJ
AJ that is such a bad analogy!
1. There is no such thing as a new woman
3. However there are always new problems.
2. Even the same one is not the same one - (I get up in the morning and think ... who am I married to today? The evil wife or the bad one?)

At least with the floater jet you know when it is a new one, you have already sorted the problems and the whole time you have it up your going to enjoy it

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Old Nov 02, 2012, 06:26 AM
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United Kingdom, England, Consett
Joined Feb 2012
113 Posts
Quote:
Originally Posted by mutha View Post
2. Even the same one is not the same one - (I get up in the morning and think ... who am I married to today? The evil wife or the bad one?)
I can relate on that point.

However
Quote:
Originally Posted by mutha View Post
At least with the floater jet you know when it is a new one, you have already sorted the problems and the whole time you have it up your going to enjoy it
This also applies to the wife analogy.
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Old Nov 02, 2012, 06:28 AM
More coffee, please!
sir_clive's Avatar
Austria, Wien, Vienna
Joined Jul 2011
658 Posts
Rotfl
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Old Nov 02, 2012, 12:58 PM
Just thumbing through...
victapilot's Avatar
United States, SC, Simpsonville
Joined Feb 2009
4,430 Posts
Quote:
Originally Posted by ajbaker View Post
IIRC, I did notice more holding force when the brake was set on another plane. I will put together a couple of setups and measure "brake on" / "brake off" current and see if there is any difference. Sounds like "wax on"/ "wax off" huh?

On my Radian, it does not matter whether the brake is on or off. The prop will fold back and stop spinning.
AJ
Update: It would seem that both of our perspectives are eminently correct. Read this: http://www.rccrawler.com/forum/elect...principle.html
It sure cleared up what is going on for me. Especially the soft, medium, and hard brake settings.

I did a quick test, using my hotliner (click my avatar to see it). Held it in front of an electric leaf blower set at mid range, claimed to be 150mph. The prop spins like a banshee with no radio on. With radio on and throttle off the brake is effective, but the wattmeter shows 0.0 watts. On wot that plane goes close to 400watts.

Good news for long flight times!!
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Old Nov 02, 2012, 04:15 PM
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Joined Jun 2012
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Originally Posted by mutha View Post
AJ that is such a bad analogy!
1. There is no such thing as a new woman
3. However there are always new problems.
2. Even the same one is not the same one - (I get up in the morning and think ... who am I married to today? The evil wife or the bad one?)

At least with the floater jet you know when it is a new one, you have already sorted the problems and the whole time you have it up your going to enjoy it

True.
My first plane the EZ Hawk, got scraped when the motor fell of at full power.
Then got a stinger64 good plane but sold to get the zephyr v70 along with a 450 heli.
Now got the AXN (just like the EZ) mods up, selling the zephyr due to not having much luck even I am a good jet pilot.

AXN is the plane for life unlike the "Plane of the year".
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Old Nov 02, 2012, 06:43 PM
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The 'wife' analogy certainly sounds about right. Having gone through a divorce I know first hand that there are far better models out there. But then again, it could just as easily be the same for so many things; cars, TV's, other electrical equipment etc.

Having owned about 25 -30 different cars over many years, I gradually discovered what I would call 'crap' manufacturers and after that, avoided cars by that maker like the plague.

I also found cars that, for me, were well made, reliable and value for money. I'm not going to name any of those car manufacturers as it'll start a bun fight. But I've now had the same car(1991 model) for 12 years and it's never let me down, despite infrequent servicing. It still turns heads, has lots of go and gets me from A to B in comfort.

If one day, for whatever reason, this car finally died and couldn't be fixed I'd seriously look at getting another of these rather than try my luck at another make that I know little about.

So it is with my AXN.

I have about 7 or 8 other planes that I take to the flying field 9not all at the same time) so one weekend I'll take a warbird, another glider and my AXN, then the next weekend, a bipe, my ST360 and my AXN.

So often I come back home having had a less than joyful Sundays flying because, either the wind was too strong or too gusty, I had some hard 'landings' (we'll not call 'em 'crashes' eh?) or I just wasn't on song after a hard week.

But on virtually every occasion, as soon as I put my AXN up, it was back to full enjoyment.

So, for ME, the AXN is just about perfect, reliable and forgiving- just like my car. That doesn't mean it'll be so for everyone, just as my car wouldn't be the same for everyone. Each to his or her own.

Of course I'm always trying to squeeze a bit more out of my AXN and have tried different motors, pretty much without much improvement in performance. So with this, my third AXN I'm sticking with the stock motor.

However, I would like to improve the roll rate.

I cut the wing tips off my first AXN and really loved the improved roll rate and general flying abilities so will be doing the same with this one.

But I'm wondering whether I could also improve things by extending the ailerons both outwardly (towards the tips) and inwardly towards the fuse.

Has anyone got any idea's on whether this would improve things? Would there be any down sides?

Once again, I'm not trying to turn the AXN into a hotliner. I'm just trying to polish it up a bit.

Oh- and finally, just like I always keep an eye on the latest planes available on HobbyKing etc, and regularly appreciate the lines of a new model, so I still admire the lines of new cars or women I see. Doesn't mean I'm going to grab one though. No sirree, especially as my lady sometimes reads my posts on the AXN. Eek!.
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Old Nov 02, 2012, 10:06 PM
BGR
Foam Junkie
United States, CA, Oceanside
Joined Dec 2003
1,656 Posts
Quote:
Originally Posted by ajbaker View Post
Yeah. Got it. You are the type of guy that if you had a chance to go for a new woman, you would choose the same one....
AJ
Well I don't need a new Woman, but I do have room for another one, but since the law does not allow that I had to settle for 2 AXNs.
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Old Nov 03, 2012, 12:21 AM
Registered User
Huntington Beach, CA
Joined Jan 2011
236 Posts
My wife indicated she might want to try flying an RC plane (yippee). So, I immediately bought one of these, went to Home Depot and bought some pink duct tape and lined the belly and put some pink stripes on the underside of the wings. She love the way it looks ("it's so cute"). So far, this seems like a great little plane to serve as a trainer. The only gripe so far is the noise level from the prop at higher than 50% power settings. I have read some have had success using a 6 x 4 prop to quiet it down a bit. Anybody find a similar size prop with a thicker cord (i.e. a paddle prop) that is not quite as loud. I'm OK if it does not produce as much thrust. Thanks guys.
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