Help, thinking of defecting to electric
|alex nicol||09/01/2018 18:33:53|
285 forum posts
Im thinking of converting a model to electric. I'm looking for advice on motor, batteries, speed controllers etc. ideally something equivalent to .40 glow power.
Also I'm flying on 35mhz, are there any interference issues.
All advice gratefully received
|Brian Hammond||09/01/2018 18:50:20|
|295 forum posts|
Hi Alex, don,t even think of using 35 mhz equipment with electric flight as it will end in tears and the use of binbags!
As to equipment the easiest route is to start with a complete plane with the motor and speed controller already fitted then fit really good lipo,s like graphene by Turnigy.Good Luck,Brian.
|RC Plane Flyer||09/01/2018 18:59:07|
|624 forum posts|
An electric motor equivilant to a 40 is a powerfull unit near to a 1000 watts can causes various problems with electronic systems,
Fear not though if you use a seperate battery to power the radio equipment in the plane you may get away with it
Edited By RC Plane Flyer on 09/01/2018 19:01:54
|alex nicol||09/01/2018 19:13:29|
285 forum posts
Thanks gents, up until now I've been a dyed in the wool ic guy. I think I might regard this as a moment of weakness and postpone until I upgrade to 2.4
|John Stainforth||09/01/2018 19:25:12|
|303 forum posts|
Wise move Alex. We can forgive the moment of weakness!
|Geoff Sleath||09/01/2018 20:00:22|
3300 forum posts
That's not true at all. I flew electric models with 35Mhz radio long before I converted to 2.4gHz but I used good quality receivers with digital signal processing eg Multiplex IPD or Hyperion. In fact my Multiplex Blizzard is still on 35Mhz. Like everything else you need to make a good job of the installation whether operating on 35Mhz or 2.4 gHz.
It's faff converting either way. In a moment of madness I've just changed a model intended for glow but built for electric as a test bed for an old Laser 62. I've had to go through the 'pain' of fuel proofing and mounting everything that can suffer from vibration on soft mounts, as well as fitting a fuel tank, a receiver battery and switch, none of which I needed when it was electrically powered. It's just a matter of accepting the differences, which, in this case, I do.
Edited By Geoff Sleath on 09/01/2018 20:01:16
|alex nicol||09/01/2018 20:59:38|
285 forum posts
I guess careful setup is the key. Although I need to get my head around the correct motor rating, esc and battery pack combo
544 forum posts
I bought a Wot4 a few years back, the IC version. When I got round to building it I converted it to electric.
It goes pretty well unlimited vertical on 840W with an 80A ESC and using 4s 4000mhr lipos. It weighs 85oz with battery.
Make sure you've always got some headroom on your spec. For batteries I like to use low lower C ratings of 20 to 25C, they seem to last longer, I make sure the current is OK by keeping the capacity high. For ESC I personally prefer to have 20 to 30% headroom above the planned amperage. For motor I pick something that will be rated about 10% more than I'm going to use, although it is only about 5% on my Wot 4,but I use full power sparingly. A wattmeter is essential. For props use what is recommended for the motor, starting at the lower end and increasing to get the watts I planned and it 'feels right'. In my experience the maximum size recommended has always overloaded the motor so definitely unsatisfactory. You'll feel for this with your IC experience. Yes it is crude and may not be the best way but it works for me.
I flew a few brushless electric models with 35MHz without trouble, keeping the receiver several inches away from the 'electrics' and careful aerial routing but when I built a Baronette I got a few 'unexplained moves' so I changed to 2.4GHz. However the model had the same odd moves now and then so I don't think they were glitches. My Baronette was nice in the air but so difficult to take off, after the second time of breaking wing spars it found its way to the local tip.
|Chris Walby||09/01/2018 22:41:34|
954 forum posts
Having only been flying 4 years hence brought through the electric route and have just converted to the dark side (well for me electric must be the light side).
I have a very well worn BH Speed Air 40 which was electric and now converted to laser 70.
Apart from fuel proofing, throttle servo, RX battery and UBEC the install was really hassle free, oh and removing the unwanted 1/2 lb of lead. Don't see any need for a switch (just another thing to go wrong) as I have the canopy off to fill the tank, then connect the RX battery using its plug and pop the canopy on. Usual control checks, and start the engine, final checks and go fly!
The electric set up was 900KV 60 A 700W motor with 60A ESC and 4S5000 lipp on a 11x8 prop, AUW 2.8kg
I'll get controversial here and say I think it flies better IC than electric, perhaps due to the engine mass being a bit further forward? Having said that BH did design it for IC so electric was just a retrofit solution to sell more and sometimes modifications never quite work as well as the original.
|Simon Chaddock||09/01/2018 22:54:27|
5419 forum posts
I use 35 mHz with 'modest' electric no problem but then I fly alone most of the time.
Just remember that with 2.4 you really must have at least a diversity antennae or better still a satellite receiver.
2.4 with its tiny aerials is much more sensitive shielding and orientation unlike the long wires of 35!
4193 forum posts
I flew electric power on 35 MHz from the days of brushed with nicads through to brushess with lipo using a variety of different Rx's (including home constructed) without any problems. The level of power isn't a factor when considering interference, it's down to taking common sense precautions with the power & rf placement in the model.
|alex nicol||09/01/2018 23:48:02|
285 forum posts
I've just dug out an old bh home run airframe that had an Irvine 53 fitted. never being one to do things simply, I've a trike set of turnigy electric retracts I'm thinking of fitting as well. my thoughts are to use separate batteries for RX and motor with both as far apart as possible. ideally I'd like to turn an 11 or 12 inch prop and have a reasonable degree of vertical performance. how do I calculate, motor, esc and battery required
|Percy Verance||10/01/2018 06:45:44|
8109 forum posts
Like Geoff I flew electric on 35mhz using Multiplex IPD receivers. Never a problem if you take care with installation. I understand some other makes of radio gave problems though.
For a while I used a 35mhz Futaba FF9 tx which came into my posession. That also worked well with an Mpx IPD rx, and again no issues on electric.
As a starting point I'd look at the 4 Max (Purple Power) website. On there you will find a comprehensive list of recommendations for motor/battery/esc combinations for many popular models. It should give you a fair idea. George Worley is the man to speak to if you ring 4 Max for advice........
Edited By Percy Verance on 10/01/2018 06:50:36
|Brian Cooper||10/01/2018 08:31:19|
435 forum posts
I flew electric-powered models on 35Mhz but with Futaba PCM receivers. These gave 100% solid reliability and no hesitation whatsoever.
As has been stated, the cheaper PPM receivers were prone to glitching and twitching with electric motors. They also went "moody" with cheap servos.
2.4Ghz seems to have ironed out a lot of problems but beware, it isn't the Holy Grail -- a careless radio installation might cause some issues.
|bouncebounce crunch||10/01/2018 08:32:23|
1739 forum posts
|Nigel R||10/01/2018 09:23:41|
2985 forum posts
what bbc said!
Electric is cleaner and needs less setup time at the flying site, but needs more time at home. Total amount of faff doesn't seem to be much more or much less. Whether that's useful to you or not is up to you (it is for me). Your models don't fly better or worse at this kind of size, with either drivetrain (in my opinion).
"my thoughts are to use separate batteries for RX and motor with both as far apart as possible. ideally I'd like to turn an 11 or 12 inch prop and have a reasonable degree of vertical performance. how do I calculate, motor, esc and battery required"
Can of worms!
I wouldn't bother with separate battery. The regulators present in 99% of ESCs are as good or better a solution for RX/servo power.
I found 20 sized airframes are a (much) cheaper and easier route to getting used to the quirks of electric power.
Talk to the shop you're buying the kit from. Or your clubs electric whizz (there will be at least one).
For what its worth, 4max list a setup for the Sebart Katana 50 which is somewhat similar to your airframe:
Edited By Nigel R on 10/01/2018 09:29:17
|Mike Blandford||10/01/2018 11:20:54|
522 forum posts
If using 35MHz, do a range check (Tx aerial down) and make sure the controls work OK at various motor power levels. I flew electric on 27MHz (Astro 25 + 16 1Ah NiCds) perfectly OK, and flew a lot with 35MHz. The only problem I ever had was with a twin with long wires from the battery to the motors (in spite of extra capacitors near the ESCs.
The mode flew OK, but occasionally glitched. Changing to 2.4GHz did fix that.
|Piers Bowlan||10/01/2018 12:53:15|
1826 forum posts
I flew electric with 35mHz (Fleet and Futaba) for years with speed 400/600 and Astro Flite brushed motors. Far more chance of interference with a brushed motor sparking away, I would have thought, but never so much as a glitch. I was always careful to place the receiver (and aerial) well away from the motor and ESC.
|alex nicol||10/01/2018 23:20:17|
285 forum posts
I'm currently flying Futaba FF9 tx and GWS ppm receiver on 35 MHz and have never had a moments trouble with it on ic.
When ever I do a set up, I always keep the receiver/Arial away from battery and servo leads. also try and avoid coiling up excess cable where possible. in extreme cases I've extended or shortened cables to fit.
I must admit over the years I seen many so called 'glitches' that I'd put my mortgage on we're down to poor installation, or duff batteries, -ve lead corrosion etc.
Thanks for all your responses, I've certainly got plenty of food for thought
|ted hughes||11/01/2018 01:40:59|
466 forum posts
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