mackey1

My Feedback: (24)

Hi,
I have a Great Planes Electric Cub that comes with a "Goldfire 550 motor. I have seen ads for 280, speed 400, etc. motors. My question is this, where in the line of motors does a Goldfire 550 fit? Is it larger or smaller than a speed 400? If I wanted to go up one size motor, what should I buy?

Basically I would like a listing of motors by size. How big (amps) ESC should I use with this motor?

Bill

Steve Lewin

550 is the motor manufacturer's designation (Mabuchi not Great Planes, they just stick a badge on them). It is basically the same as a Speed 600.

I guess you want to improve the performance of your plane but in electrics we don't usually put a BIGGER motor size in just a more powerful version of the same size or perhaps one with a gearbox or even just a different battery (with more cells). I'm sure someone knows that plane and can give you more detailed help.

Steve

jollyroger

My Feedback: (6)

Mackey1, To get the best performance for the electric cub you could use a brushless motor. That being said, for starting out they are quite expensive, yet there are alternatives.
The Goldfire 550 is a typical can motor with efficiency somewhere around 65-70%. By adding a gearbox w/ 2.5:1 ratio it will swing a larger prop thus providing more thrust.
I would recomend no more than 8 cells w/ this setup. For more power at the same price purchase a Kyosho Magnetic Mayhem motor. It is the same size but is more powerful than those cheap can motors. They have replaceable brushes and can be purchased in two versions: Counter clockwise for direct drive and reverse rotation for gearboxes. If you plan to use a belt drive you the standard rotation as the belt drive operates in the same direction as the motor.
I have succesfully flown my Electric cub this way. A direct drive simply does not work unless you plan to use a Jeti phasor brushless which is designed to spin larger props.
Direct drive with a 550 is marginal at best for this plane or any other in my opinion.
With the Magnetic Mayhem, some people are using gear ratios as high as 3.5: 1 at 10 cells. However to get the most efficiency you would need to use a larger prop and the Cub doesn't have enough ground clearence. A 2.5:1 or 3:1 will be fine for this type of plane. Keep the current draw below 35 amps, 30 is best for extending the life of the motor. As before use 8 cells for the 2.5:1 and try using 10 cells with the 3:1 . Prop size will vary with higer ratios. A 2.5:1 you can use a 10X7 and I have even used an 11X6.
With the 3:1 , an 11X7 or maybe 12X6 could be used.
Use a good ESC with BEC ith a 35 amp rating. Forget the switch.
An excellent book is available for those just getting into electric flight. "Entering Electrics" by Harry Higley is the best book for beginners or anyone for that matter who fly electric.
Good Luck! Until then , Fly quietly and clean> Jollyroger

blvdbuzzard

thank for the help. I am going to scratch build #2 in the near future, and was wondering what motor battery setup would be a good one. For me the brushlees is out of the money window so I was looking at the MM and gear box combo.

Who makes a good middle priced gear box? Should I bit the bullet and get a really good one or just a middle of the road one???

When you help one person you may end up help several.

Dru.

jollyroger

My Feedback: (6)

blvdbuzzard: You pay for what you get is the old adage, however Master Airscrew gearboxes are a good inexpensive gearbox. An Astro flight gearbox is probably one of the best at around $35 -$40 dollars very smooth and rugged. Get one for the 035 motor in order to get the right size pinion dia.
I suppose the Great Planes will also work as long as you don't nose it over... has a tendency to rip up spur gear/shaft.
Also Tom Hunt's belt drives are a very good choice. They can be purchased in a variety of ratios and are efficient.
Good Luck! Jollyroger
Tom Hunt is Model Air Tech. See their website.

blvdbuzzard

Thanks for the info on gear boxs. i do know about getting what you pay for, I fly heli's too. I just did not want to dump a bunch of money into it. I know I could spend lots of green on a brushless and some 3000 battery packs but want to maintain a cost level. I dont want it to cost as much as one of my Helis.

I will look at the belt drives.

Dru.

BillBo

My Feedback: (6)

I've been flying my ElectriCub using an (old) Astro 05 geared on 7 Cell, 1700mAH packs, with a Castle Creation 35 Amp speed control with BEC. I use either a 10x9 or 11x7 prop. I've used this same combination with different speed controls for 12 years in a Goldberg Mirage 550. The performance is satisfactory and I get flights up to 10 minutes with proper throttle management.

I've just purchased a brushless motor and controller which I'm excited about trying. I'm still planning on using 7 cells, cuz that's what I have - but 8-10 cells would give better performance.

You'll love the electricub. Mine is covered with Nelson's Color fab.