I see this was your first post, WELCOME to Stunt Hanger welcome back to control line & welcome to ECL.

It sounds like you have a pretty good set-up there, hope you can post some pictures.   Which E-FLite motor is that?

Forgot to answer your question. The motor is an E-Flite 46, 670 kV, 40 A continuous.  The whole ship weighs 2.8 lbs, but will probably gain another few ounces when finished.

John

John,

Looks really great!!! I am wondering if you are going to be a bit tail heavy with the battery that far back? Anyway, I bet you have that "potential" problem covered. (no pun intended)

John

John Witt wrote: "My hope is that it is like riding a bike and there are still a few reflexes left to help the first time out. It is really not a trainer, so I'm concerned about over controlling and PIOs. I plan to keep a stiff wrist and elbow for the first bit for sure."

John, Set your timer for a reasonably short time!!! If you are not planning on any maneuvers (loops, lazy eights etc.) on your first flight after a long long layoff from C/L flying you may get dizzy!! (don't ask how I know this) The timers that I am using have about a 2 minute minimum and that can seem like a very long time!!!!

John

Thanks guys. I wasn't sure about how the motor ratings translated to glo-engine equivalents, and I thought I might move the motor eventually into a bigger/heavier pattern type ship. I plan to set it at 70-75% power and yes, just a couple of minutes duration for the first bit. Definitely no triangle 8s until at least the second flight  .  You know the old hot rod adage about no substitute for cubic inches.  I was figuring the Panther would be about 4 lbs, so it's lighter than I thought. Not the way my stuff usually comes out.

My wife came into the man-cave where is build models and I was in the middle of the room turning around and around (5-sec/rev). I got the strange look, but she didn't say anything.

Thanks for the good info. I should have found this forum before buying any gear, but I don't think I'm in real bad trouble yet.

JW

I have zero experience with this, so tell me what you think. I have a APC 11-5.5 prop, so at 13.5 V loaded, that should spin about 9000 rpm.  Does the ESC work by voltage or current limiting? I would expect it to limit the current by reducing the on-time of each phase to control the power output and reduce rpm. 70% would only be 6300 rpm, 75% would be 6750. 

Can you tell me what the approx no-slip speed would be for that prop pitch? How does the 9K RPM compare with a Fox 35 stunt swinging a 10-6 prop?

Lastly, would you point me to some info about the way the motor/controller combo works. I was thinking that the setup looked like permanent magnet, with a multi-phase circulating field.

JW

I have zero experience with this, so tell me what you think. I have a APC 11-5.5 prop, so at 13.5 V loaded, that should spin about 9000 rpm.  Does the ESC work by voltage or current limiting? I would expect it to limit the current by reducing the on-time of each phase to control the power output and reduce rpm. 70% would only be 6300 rpm, 75% would be 6750. 

Can you tell me what the approx no-slip speed would be for that prop pitch? How does the 9K RPM compare with a Fox 35 stunt swinging a 10-6 prop?

Lastly, would you point me to some info about the way the motor/controller combo works. I was thinking that the setup looked like permanent magnet, with a multi-phase circulating field.

JW

Well to get you in the ballpark, my Nobler flies 5.0-5.1 sec laps (~63 foot center to center) with an APC12-6 Thin Eectric running at just less than 8000 rpm. As I recall, when I first flew the Nobler with the APC11-5.5, I was running over 9000 rpm. I am not familiar with the Panther, but others flying larger planes, (like the Brodak P40) are running the APC12-6 prop in the 9000 rpm range for acceptable times.

I also think your kV is too low for a 4s pack. Last year I ran the Nobler with a 730kV motor (Scorpion 3014--admittedly a lot smaller than yours), and I was running out of voltage at the end of the flight with a 4s2100 mAHr pack and the 12-6 prop. My guess is that you would need a prop at least as large as the APC 12-6, and probably larger.

The ESC tries to get the rpm by increasing the width of the current going into the motor. Roughly speaking, this is "sort of" equivalent to having a variable voltage battery (it would be equivalent if the rep rate was high compared to the motor inductance/resistance time constant).

We typically claim you should shoot for 75% of the kV*battery voltage, which should give you the extra power needed for the overhead maneuvers.

Yes.  We'll be there in the morning.  I hope to see you then.