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brushed to brushless! Answered

If you have been flying your RC planes a lot and have found them getting a bit boring, go brushless and get lithium polymer cells.
brushless motors are lighter and twice as powerful as brushed. lithium polymer batteries hold the most electricity to weight ratio compared to standard Nicd and Nmh. Dont believe me look at your cell phone open the battery hatch and take out battery its probably a Lithium polymer or lithium ion notice how light it is and small it is now look at the volts/ mAH pretty amazing hu? Got a laptop it probably got a lipo to.
you want to make the switch but dont know what motor, battery, ESC (ESC-electronic speed control) to get, just ask and ill give you a hand! i will need to know the motor and battery that came with the plane/ or that u are using. Are you flying glow (gas powered) and wana go electric? i can help u out their too!
Their are 2 kinds of brushless motors outrunner and inrunner whats the difference? well outrunners spin slower with more power so it acts like it has a gear box (this eliminates the need for a gear box reducing weight and noise) it also has a different design (look at pics). inrunners have a brushed appearance but their much lighter and more powerful u might need a gear box through.

update 2/20/08 new image added (not all comment boxes are working)

Discussions

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abstract_genius

10 years ago

I have a couple Motorolla Razors each phone has a BR50 3.7V Lithium Ion battery in them. I would like to daisy chain them together and make it into a quickly chargeable 14.4V RC battery if possible, but I can't find the amperage on the batteries anywhere. I have an Off-Road Truck I would like to throw it on, but I would like to keep it on a minimum of 3000mA. I also am unsure about the number of pins on the battery (it has four). Above the leftmost pin it has a + sign, and the right most a - sign, but I'm not sure the importance of the middle two pins. Have you ever converted similarly available batteries with any success for such use, cause I would really like to keep my outrageous RC upgrade costs to a minimum. I currently am using an old Ni-Cd 7.2V that wont hold a charge. Nice topic :}

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killerjackalopeabstract_genius

Reply 10 years ago

Try this out, get seven or eight (eight is slightly over at 16V seven is slightly under at 14V) jessops AA size nimh camera batteries, it'll be cheaper than a commercial battery running about £40 altogether, buy the quick charger that they have in store and it's really fast, that mean two chargers and two four cell battery holders in series. the batteries are 2700mah.

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abstract_geniuskillerjackalope

Reply 10 years ago

Thanks for the suggestion. I know I would really like to keep the footprint of these things pretty small (I would really enjoy the size of the cell phone batteries), but at the very least I could run my radio on these. I'm currently running Ni-Cd AA's in my radio, but they don't charge so fast. I still think they would work alright cause of the bigger six-cell pack I'm using anyway.

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killerjackalopeabstract_genius

Reply 10 years ago

I suppose the other option would be lithium AAA's which provide about 1000mah and are far smaller... I suppose its all relative, for the AA's that adds up to a ridiculous mah value, the footprint would be small enough for a larger car and if made out of two packs then wight ditribution can be played with, then again power wise your motor may not be up to shifting that weight fast..

seems like it would be a little easier to get a normal battery. it will be much simpler to just buy a battery. You mean 3000mAh (milliAmp hours) right?
Thunder Power Prices:
7.4V 2100mAh 2-Cell 49.95
11.1V 2100mAh 3-Cell 69.95
14.8V 2100mAh 4-Cell 99.95

Flight Power Prices:
7.4V 2100mAh 2-Cell 41.99
11.1V 2100mAh 3-Cell 62.99
14.8V 2100mAh 4-Cell 83.99
Largest Lipo i have is a 4250 mAh 11.1v

I meant mAh, but I'm not sure how to determine that from voltage and amperage, and am only making an uneducated guess that the Amp values are posted that way. I checked out pricegrabber.com, and they had these (BR50-OEM versions) batteries for about 5 bucks a pop. I already have two, so I figured get away cheap ($15 + Shipping) and small. I already have the phones I could use to charge them, and they do charge pretty fast.

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abstract_geniusabstract_genius

Reply 10 years ago

I did some looking around tonight at some RC forums that address these very questions. It seems I really need to consider the average amount of amps I draw over a period of time (How I do that I have no clue). I can then take a factor of about 75% to 80% of efficient usage of the amp hours a battery is rated for. They also stated that an 'Amp Hour' is exactly that; how many constant Amps or in my case mA could I draw in 1 hours time. That still sounds OK to me somewhat (remember I'm pretty uneducated in the electronics arena). I figure my wires going to my speed controller & the draw of my brushed motor are the limiting factors of how much amperage I draw FROM the battery??? If I have an over-abundance of available amperage at operating Voltage Specs. then I should still be OK to use these little monsters (please/maybe)??? Considering I'm racing a truck around instead of flying, I would imagine I would 80%+ of the time be using full throttle/amp-draw. I guess my big question is would my thought process fry my motor, servos, and speed controller, radio, etc... Or am I OK?????

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abstract_genius

10 years ago

OK I looked up the specs of the batteries and found they run at 710mA. to reach and exceed my minimum amperage I would have to run 5 of these @ 3550mA, but I'm not sure what I can do to limit my voltage other than adding resistors, and in turn I'd have heat issues I don't want. !!!!Alternatively !!!!! I think I've read educational resources in the past that describe how to link batteries in parallel to increase Amperage and run the batteries in chain (neg-pos-neg-pos-etc...) to increase voltage. Electricity experts please respond to this. I'm thinking if I run 3 batteries in parallel, and two batteries in parallel, and then run those two groups in chain, I would get my desired 14.4V @ 3550mA. Is this correct? If this is true, I'll order 3 more batteries. The real-estate of these things are really small, and I would really like to keep a nice little power brick like this tucked into a nice little niche of my RC truck. Battery Pak #1 Battery #1 (+) to Battery #2 (+) to Battery #3 (+) Battery #1 (-) to Battery #2 (-) to Battery #3 (-) Battery Pak #2 Battery #1 (+) to Battery #2 (+) Battery #1 (-) to Battery #2 (-) Battery Pak #1 & #2 Combined Battery Pak #1 (+) to Battery Pak #2 (-) Battery Pak #1 (-) to Battery Pak #2 (+) Then use Battery Pak #1 (+) as battery combo positive Then use Battery Pak #2 (-) as battery combo positive

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Kira_Koenig

11 years ago

It's amazing (if not depressing) how the small stuff like foam friendly glue, servos, control rods, clevis, and all that add up quick. pretty soon moths are flying out of your wallet. :D

luckly the kit was only 24 bucks, it came with motor (brushed) carbon push rods, supports, it also came with control horns and zbends it even came with a fire wall mount costume made for my brushless rimfire motor. it even came with a strip of velcro. to bad it didnt come with a battery and servos.

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Kira_Koenig

11 years ago

Thats exactly why I am getting into electrics. I can launch them by hand and catch them by hand (hovering close enough to grab it). I think they are more fun than the glow and gassers. I love flying at ball fields in the evening, it's more relaxing and I can enjoy flying that much more!

brushless and lipos are expensive i spent 200$ on a kit, motor, 2sevos, (i already had 2) battery, prop, glue and a bunch of other small stuff.

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CameronSS

11 years ago

I'm not normally a spoilsport about chemicals and technology, but I have seen many firsthand reports in RC forums about the dangers of LiPo batteries. I have never had problems with them, but apparently if you overcharge LiPos , or especially if you rupture the casing, they can spontaneously ignite and/or detonate. That said, I love LiPos. Just be careful with them. I saw in an old RC Modeler magazine an article about taking the door motor, I think, off an old computer optical drive, adding magnets, rewinding coils, and otherwise modifying it to make a cheap (comparatively) brushless DC motor. Next time I score a deal on cheap neodymium magnets I'll make an Instructable on that conversion.

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you also shouldn't short them out. I always keep them in a tin can and charge them with my electrifly Triton charger with a 20 foot cable. Iv heard that if you smell a fruity smell coming from batteries then u have a damaged cell and you should leave it in a bucket of salt water out side overnight away from flammable stuff, then dispose properly

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royalestelCameronSS

Reply 11 years ago

They can indeed explode. Had some HAZMAT training once where they related a explosion of a crate of old litho batteries a forklift was carrying. Some pieces landed 300 yards away . . .

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Kira_Koenig

11 years ago

I have a Futaba 8ch (ch53) Heli PCM radio, that I have had for around 6 years. I have been selling a lot of my stuff including my Vigor 60 heli. I quit my local club due to a lot of really Obnoxious members there. So I have really been getting into electrics. I use mostly Hitecs stuff in my electrics. They are cheaper and more reliable than any other brand. -Where do you fly at? I used to fly just outside of Florence SC (the home of Kirk Grey 3rd place TOC pilot and I think he was 5th in the world back in the late 90's). I also have been to Triple Tree (Joe Nall), which is 3 hrs away from where I live.

i live a little farther north than SC, my local flying club is actually an hour away. but for some of my smaller park fliyers i just fly at a large large field (its 2 soccer fields and 2 baseball fields its deserted on Sundays during the summer) For my new reflection i will probably be able to fly in front yard because its a indoor-outdoor 3D plane.

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Kira_Koenig

11 years ago

CameronSS, -I don't want you taking this the wrong way, you can build components individually and make a truly scratch built R/C plane, but no cigar on it being cheaper. Micro sized aircraft are MORE expensive. Servos can cost $20 or more, receivers $50 or better, and batteries $30 or more. I know, I have worked in a hobby shop for 3 1/2 years. I have flown, gas, glow, electric, turbine, planes, jets, helicopters, cars, and yes boats too. I also have built and repaired at least 1 of everything listed. -You want to stay in what I call the Standard range. Using stnd servos, motors, and electronics. They are used more and are cheaper. For example, a standard servo cost $10 where as a micro servo cost $20; See my point, if not look it up on the web. - Finally, Yes, Instructables are just that, but they do not have to be cheap. I also know most Diy are trying to save money. However, R/C is not really one of those hobbies that you can do that in. I have never seen someone get into R/C under $100, EVER (unless it is cheap one flight stuff). You have to take in consideration of Radios, servos, receivers, batteries, starters, chargers, and what ever other support equipment is needed. If you don't have $50 for a motor, How can you have money for a radio (and there are FCC restrictions on what frequencies you can use and etc.) to control it? -Think about it this way, If you post an instructable on how to build a shop, chances are your not going to grow the lumber, cut it, cure it into boards? Or gather surplus steel melt it down into your special made molds for nails? You probably would say go to LOWES and buy this, this, and this! Then show step by step on how to assemble the shop, would you? I think you would exhaust more resources to REALLY scratch build something like that. Sometimes it is cheaper to buy than build......I have learned that the hard way myself!

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Kira_Koenig

11 years ago

-Yeah, Cameron is right they can be dangerous..... store and charge them in a ceramic jar for safety. I would also keep a chemical extinguisher on hand as well. -You can make your own brushless motors from cd rom drives, but it is difficult and doesn't give enough power for any semi large ( bigger than 12in length/wing span) models. You can buy ready made motors for around $50 that will give excellent power output on a 15amp ESC. I know a guy that did a conversion of one and the model was only 10"x8". The electronics that he had to use to fly it far outweighed the savings on the motor. But none the less it is fun!

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CameronSSKira_Koenig

Reply 11 years ago

Little models are more fun...cheaper (usually), less space required to operate, and doesn't hurt as bad when it dive-bombs your head. And I don't have fifty bucks to blow on a motor. What kind of Instructabler are you? You buy something that you can build?

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Kira_Koenig

11 years ago

By the way The Triton charger is one of the best I have ever had, very reliable. I have also joined your group and I will try to post some of my projects when I get a chance. Do you fly foamies, lite balsa and film, or both? One other thing, are you a Futaba person, JR,or Hitec person? Thanks!

Right now im flying foam 3-d trainers. the u can do, and this weekend i hope to fly my new reflection
before that i have been flying a variety of park flyers and even a few unpowerd/powerd gliders, My favorite park flyer is the wingo it is a near indestructible foam park flyer even after a bad crash with wings and tail broken in half some epoxy and next day she was up and soaring. With a brushless motor i could take her strait up until she was out of eye sight! I even flew one out of radio range (apx 4 miles strait up) i never got it back, the plane glided with the wind and could have traveled hundreds of miles at that height or she might have just dropped out of sky a few miles away either way i will never see her again :"(
Any way i have always used Futaba channel 25 (thats my reserved channel at my club so no one else can fly 25!!!) Right now I have a Futaba T6EXAP its nice, you can program 6 different planes with different throws trims and different reversed servos.

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Kira_Koenig

11 years ago

Man, you should check Weiss's post. All sorts of strange things have been going on, like he said getting logged in as a different user and stuff! I got your message though, I fly the 3d stuff too. I usually by from a local builder, he makes foam cap 232's from a thicker, better, more durable foam. I forgot the name of the foam, it's the same as the great plane's, but thicker. I don't see how people build with that thin stuff, I tried building an Ikarus Yak, the foam was warped and halfway through building it I destroyed it. it's just to thin for me.

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i had 2 comments poasted on here and now their gone? what happend!

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Kira_Koenig

11 years ago

Himax brushless motors and Thunder power LiPos are the way to go! I also would use Kokam LiPos as well I have a couple that have served me well. Electric motors are more responsive and more powerful than Glow or Gas. Cleaner too! :D Are you using Castle Creation ESC? How do you like them?

no i use mostly electrifly for my ESC and motor they all use the same plugs so i only need to solder the battery plugs. I have a thunderbird 18 ESC and it was a PITA to program. E-flight also has great motors, servos, batteries, and ESC's
But iv heard the Castle brand has some great reliable stuff.
You should join my group so far theirs not alot of people on their or instructables but i hope to get a new type of instructers/instructables