Electric powered free flight

[woundedbear]

I know I have posted this before But I still have an entrust in doing an electric powered free flight model airplane. I have looked high and low for a count-down timing device for an electric powered free flight model and nobody sells such a thing I have owned several wrist watches that were very light that had this feature. I am not very well schooled in electronics," but who is?" When you buy the latest computer or cell phone the newer and improved models are being unloaded off the trucks at the back of the store The world of electronics is changing so fast I don't think anybody can keep up with it all However it seems to me that an adjustable count-down timer for a brushless electric motor powered system could be easy to designed and manufactured for free flight model airplanes. But why doesn't anyone produce such a thing A small light weight brushless DC electric motor with a Li-Po battery power source and a electronic speed controller would make for some fun free flight model airplane builds. So why doesn't any manufacture make a timing device for free flight model airplane builders With such a device building a free flight model airplane could be so versatile, you could adjust the run time of the electric brushless motor to fit the size of the flying field and could build a much lighter model. This would create a whole new class of free flight model airplane building and it would be fun thing to do Why doesn't a company (like the Timex digital watch company) make such a device The company that would make such a count-down timing device for model airplane builders could sponsor a free flight contest to promote their other products Of course such a device could be used by some "kooky terrorist group" to hurt a lot of innocent folks, but they,"the kooky terrorist groups", are already doing this sort of thing. I am sure if you gave one of these, "kooky terrorist groups", a tube of toothpaste they could come up with a way to cause harm. So why can't I, "who is of no threat to anybody", have an adjustable count-down timing device for making my hobby of building and flying model airplanes a little more fun? I don't understand why such a device isn't available for building a power system for model aviation

[tom arnold]

That device has been around for years and is used by about all the electric flyers at the FAC Nats. You can set the timer from zero to 120 seconds, set the power level, and even adjust it to slowly take off the power such that the model doesn't seem to hit a wall when the propeller stops. The Hippocket Aeronautics site has an entire section devoted to electric flight for more information.

[woundedbear]

thank you Mr. Arnold I'll look into it.

[scigs30]

You can build your own pretty cheap, much cheaper than buying one. There used to be capacitor brushed motors that were pretty easy and cheap. If I was going to go brushless might as well just make it RC.

[Bill Gaylord]

You can build your own pretty cheap, much cheaper than buying one. There used to be capacitor brushed motors that were pretty easy and cheap. If I was going to go brushless might as well just make it RC.

That's where I'm at.
There's not much to these other than a pot, resistor, cap, timer, momentary switch, and fet. All cheap parts, where I'd be building my own before paying what they want for them. There's not much there, and compared with mass production BL ESCs, they would probably be $2-$3 if mass produced, or basically the cost of shipping. With the remainder of R/C gear eliminated, brushed power is quite practical. With BL as you stated, may as well just build an R/C aircraft.

[woundedbear]

Bill Gaylord thanks for your reply. Could you post or send me a personal e-mail with detailed instructions on how to build my own count down timing device for a brushed electric motor set up? And if you could send me a link where I could buy the electronic parts and a brushed electric motor for an electric powered free flight model airplane it would be a big help. I have been picking everyone's brains here of the Guillow's forum for a long time now and I have learned a lot. However my present skill level as a builder is still limited so, I am now building rubber powered planes only. I have thought about it and this is the logical place to start. I had the idea that I could start out doing Guillow's RC conversions but I can now see first you have to crawl before you can walk and I was wanting to start out running, "big mistake" on my part. "I will", one day do a Guillow's RC conversion, but first I will have to do what everyone else on this forum has done, start out building rubber powered free flight model airplanes. Then work my way up to the difficult stuff WOW! that was something I should have been thinking about the whole time Start with the simplest builds and work my up to the more advanced building projects. I wish I knew more about computers too but I don't there was a video I would have liked to have posted here on the forum. In this video which was filmed at a free flight contest in the UK. Some guy had an electric powered free flight model airplane, I'm not sure, but it looked to be a small 1/24th scale Piper Cub, this little thing just kept flying around in a large circle, must have flown for over 4 minuets I was very impressed to say the least That video put the whole of electric powered free flight into my head, I guess you could say it put a "bee in my bonnet". I've just got to build one to get it out of my system, but the simple rubber powered models come first One more thing I would like to do is thank each and everyone of you guys who have given me advice here on the Guillow's forum, all of you have helped me a lot, thank you

[Bill Gaylord]

If you search, you can probably find a simple timer circuit online. I don't have any onhand, but this is probably a good 7555 timer circuit example:
https://encrypted-tbn1.gstatic.com/imag ... HSLy6qLi_q

Again there's not much to these circuits. I built a lipo cutoff before they started selling them as an add on for the older brushed ESCs some years ago. It was lacking in that it didn't have restart, but all there was to it was a simple gate resistor chosen to work with a specific cell count lipo, which would drop out at around 3.7V per cell.

[woundedbear]

Gs' Bill could you have posted this schematic any smaller And what is a gate resistor

[Bill Gaylord]

Gs' Bill could you have posted this schematic any smaller And what is a gate resistor

Yeah they're schematic could be a bit larger. The gate resistor mentioned wasn't for a timer circuit. It was simply used to calibrate the voltage point at which the FET drops out, and stops running the motor, used in conjunction with a speed control. Completely different subject there, but similar along the lines of experimenting with circuits for models.

[dirk gently]

DSCN0849.JPG

Here's my attempt.
Built roughly according to the schematic for the Peterborough FET timer: http://www.peterboroughmfc.org/technica ... Ttimer.pdf
It has, however, an onboard variable resistor, and therefore doesn't need a zapper, can be zapped using a 9V battery. The FET is a D16NF, the same size as the D12NF, but good to 16 amps of current draw.

This is a quick-and-dirty prototype, but despite that, it weight next to nothing. I haven't made any flights with this one yet, but made stationary tests and it appears to work great.

[WIDDOG]

This site sells excellent FF Timers..http://microflierradio.com/

[WIDDOG]

here's a vid of a Micro Fliers Timer in action. I once had one set on 30 seconds and it flew away on me. https://youtu.be/2IPc3XwTAz8

[scigs30]

Heck this would be cheaper.
http://www.banggood.com/ZhongTian-Assem ... 21583.html

[WIDDOG]

The toy plane is probably like the Air Hogs Wind Chaser. It doesn't even have aTimer. It charges a small battery in the model. The model flies and de charges the battery in about two minutes.

Now the Hobby Grade Timer from microflierradio.com can set the time and throttle control.


https://youtu.be/e6HIQq5eZ6o

[WIDDOG]

I have been having problems with the gear drive motors. They are expensive and don't hold up well. I have been having better luck with direct drive units.