THE MAIN POINT: I am looking for the full electric setup for a Twister. My end goal is to electrify a Twister and have a battery that can fly the full PAMPA pattern.

THE FULL STORY: I am just a year into Control Line flying/building. My son and I are still very green in the sport. We just got beyond the crashing phase with our trainers and are looking towards our next plane(s). We fly electric. My hope was to find a plane that could compete in "Profile," "Nostalgia," and "PAMPA" stunt competitions. I commonly find these three events available at a flying competition, so I wanted to go with a "one size fits all approach" so that we could redundantly fly the same type of plane and hone our still developing skills. I settled on a Twister and have already bought several kits. No use recommending a different plane, I already have the kits.

Before I talk electric setup, I have noticed talk about Fancherized or Francherized Twisters. Is this an acceptable design that fits the Nostalgia 30 general rules? I would hate to think I am in the clear only build the plane and find it is disqualified. I haven't settled on a specific modified Twister style, so if you have thoughts, toss them in. However, I have found many Twister threads discussing modifications, so don't bog me down here. My real goal is identifying an electric setup.

As for the electric setup on the Twister. I need a setup that can get us through the full pattern mindful of battery and motor weight. I am an electric setup novice, but my current experience is with a Cobra C-2814/12, KV 1390 on my trainer planes (see full specs here https://innov8tivedesigns.com/cobra-c-2814-12-brushless-motor-kv-1390). I mounted this motor on a Twister and can get about 2.5 minutes on a  Turnigy 2200MAH battery running at 10,500RPMs on a 9x6e prop. The motor was practically cool to the touch after the run. It would be great if I can continue using a motor I already have, however, I would rather get the overall system right.

Please share any and all thoughts on this process. I need as much input as possible as I take on this task. Even for those that are not electric knowledgeable, chiming in on overall plane weight and CG would be helpful. It's okay to respond like I know nothing, because I'm not far removed from knowing nothing :-)  Thanks for the help!

You can't just tell us the cell capacity -- that's like telling us that each of your gas tanks holds a gallon, without telling us how many you have.

So -- how many cells?

If Ken's getting a full pattern out of a 4s 2200mAh setup, and you're only getting 2.5 minutes, then unless you're only using two cells something's wrong.  Either you're using three cells and running out of voltage overhead (in which case it should limp through a lot more), or there's something that's making your setup pull more juice than Ken's.

Ken, that’s nearly identical to my setup in the Primary Force. I’m using the 10x5.8 F2B prop, and I happen to have a KR timers on that one. Don’t get me wrong, I use Hubin timers too. I like ‘em both.

Brendan, copy Ken’s setup. It’s a good one.

Just a note on dates.  The Fancherized Twister article was published in August of 1987.  32 years ago. 
Should be just fine for N-30 with the rolling 30 year cutoff date.

http://www.marinaru.ro/forum/planuri/Planuri/zbor-captiv/F2B-Acrobatie,%20Trainere,%20Semimachete/Fancher%20Twister%20Plan%20Article.pdf

I ran the Cobra 2820 970kv, APC 11x5.5e, Thunder Power 2800/4s on my 45 oz Gieseke Nobler (RIP).  It had 30+% left in reserve after a 6 minute flight.  66ft (total) .015" lines.  It was very strong in all maneuvers.  Not lacking for thrust, at all.  Perhaps the high elevation (4500 ft) here contributes to the low battery draw, but I am puzzled why the similarly sized planes mentioned in this thread are chewing through so much battery on shorter lines and shorter flight times.

I forgot to ask as well.  If you are flying 2.5 minutes because that is what the timer is set at or is the motor slowing down?  Never let it get so low that the motor slows down.  Really bad for the battery.
What is your remaining voltage % after the flight?

One point that is not directly related but will help in the long run.  Learn to fly from between 5 and 6 minutes even if you are not flying the pattern.  A lot of things are easier if you have an internal clock that is set right.  When the motor is about to quit, the ESC will give you some warning.  It is very subtle and easy to miss.  Anticipating it can really disturb your thought process when you are wrapped up in the overhead stuff. It is not IC, you can be thinking intersections, shape etc. instead of will my engine keep running because you know when it Will quit, not when it is supposed to quit.

Another good clarity question. We've only flown the Twister 3 or 4 times just for the feel and to see if the motor is getting hot after flights. The 2.5 minute setting is self-inflicted since our Trainer planes get about 3 minutes of flight before hitting 20% capacity. I did not want to push our batteries, so I set them for a shorter time. I did not check capacity % after our Twister flights (probably would have been a good idea).

As for being aware of the time, Mike Alimov (who responds later) has worked a lot on getting us flying. He put us on to having a stopwatch and the non-flyer calls "time" with about 15 seconds to go.  You are correct that the shutoff notice is "subtle" at times.

That's a 40 amp motor, and at 10,500 RPM you're putting about 9 volts to it.  On a 48 ounce plane you need about 340 watts continuous (48 ounce * 7W/oz).  That means you're pushing about 37 amps through the motor.

That's pretty close to the current rating of the motor.  It'll probably work, but if you change anything, go one size bigger.

There is a reason so many people are recommending the Cobra 2820/12.  It is a work horse.

I left something out earlier which probably doesn't mean much in this discussion but I fly my Twister on 63' lined because that is what I fly my PA ship on.  I also duplicate the lap times as close as possible.  I fly slower than some (around 5.5) and I wanted to keep the pattern rhythm as close as possible.  Yours will probably be fine, or even better on 58-60' lines.

FYI - I am able to get the 5.5 lap time using a 3 blade Master Airscrew at 8750 rpm and I use 80% of a Turnegy 2800 4s battery timed to 5:30.  I have flown mine on 58' lines and I was able to back the rpm's all the way down to about 8400.  You are going to want to use a larger prop.  Most likely an 11-5 to 11-6 and the rotation does not mean much as you are starting out.  All the talk about left vs right rotation really only changes how the plane responds at the top of the hourglass and where it is weaker in squares.  You get a little better tension on takeoff and level flight but none of that is worth the hassle of finding props at anywhere other than the upper levels and even they are split.  The motors will run equally well both ways and it is a simple swapping of the red and black wires to change.  Your ESC may even have a setting.

Ken

"Any two motor wires", which are whatever colors the ESC manufacturer and the motor manufacturer want them to be.  Definitely not the red & black wires from the battery (in case any electric flight newbies are reading this).

Where were you when I first started in electric.   That is where my "dummy" ESC that I use for building came from .  Glad you reminded him.  I got it wrong and Castle was kind enough to sell me a new one.

Remember that smell.  Translated it says - "Open your wallet"

Ken

Hi Brendan,

Some good advice from Ken. I have modified a few of the popular profiles similar to the Twister for e-power, and my method is really simple and works very well. You build the nose with two strips of 1/16" plywood something like really thin engine bearers. You can check this out in the pics below. Then I close in this hole with a thin nose doubler on the inside of the nose which supports the esc and timer. Two Velcro straps hold the battery in place and also all of the electrickery. I use my own timers, KR Governor Timer (obviously!  ) because they are dirt cheap (to me! ) and don't require any expensive esc's with their own governors and expensive programmer's etc. It keeps everything simple and when you are getting stunt, or in your case, electric stunt, this is a bonus.

RSM stocks the timers and also some nice motors called Black Tiger. The motors for a Twister can be anything similar to that Cobra 2820. You basically need a motor that weighs around 140 to 150 grams with a Kv of around 920 to 985. The Arrowind 2820 from Brodaks is also good, and I've used quite a few of the Black Tiger 3542C-950 motors as well. The esc can be a 40 amp type like most of the better ones from Hobbyking. The ZTW range from RSM are very good as well. You just need an esc with it's own voltage regulator (BEC) and it will be fine. The magic prop is as mentioned above, the APC 11 x 5.5 E, and the battery should be a 4S 2450 mAh 25~35C. Up at high altitude where I fly here in Johannesburg South Africa, we get by with 2200 mAh for the 5 minute flights.

If you want some detailed photo's of how to make this simple e-nose for profile models then just send me a PM and I'll mail you more detail.

Keith R

Hi Mike,
Yes, it is exactly the same system, and it works really well. There are many other motors in that size which give us a nice wide range of choices. E-Max also makes the GT2820 with 985 Kv. E-Max dropped their old BL series like the one in my picture but they still supply Arrowind which is available from Brodaks. The GT version is a little smaller in diameter and has better bearings in it. I see that E-Max USA sells the GT for around $26.00. Just make sure to select the 985 Kv version.

The wing is my own and not the Tutor II and is a foam core with cut-outs and 10 mm wide "ribs", similar to Christ Rigotti's wings. It was my attempt at making a take-apart profile. If I made another one though I would not split the fuselage as it's not that long. I've added a photo of all of the parts. The name came from making a profile version of my Electron model, hence Protron and not Proton.  I've also added the plan of my very successful Eze-Pro model which has been made plenty of times out here. It shows the nose construction which I find easy to make and also works very well.

Keith R

You're moat welcome Brendan.