E-Conversion for a Nostalgia.

[50+AirYears]

Could somebody suggest a good power package to replace a glow engine in my Air Trails Sportster? It was a bit overpowered with a .19.
It will probably have to be a lower cost brushed motor. My company just "Improved" our medical insurance by going to a high deductable plan, and my $79/mo meds just went up to over $400/mo.
Its great to approach retirement in this Reganomics era.

[Sky Sharkster]

To 50+, Without knowing the weight, wing loading and size of the plane, I'd say a "Speed" 600 brushed motor is about like a glow .15. The Hobby Lobby # is GR 1793 for a 7.2 V motor, price $ 19.90. With direct drive and 8 NiMh cells it would use (about) an 8X4 prop. You might want to run a few prop/battery combos thru "Moto-calc" to check my numbers. The better choice would be a geardrive and the 600 but the drives are in the $ 30.00-40.00 range which would bring the total cost to around $ 50-60. At that cost you're getting near the price of an inexpensive brushless!
The ESC for the brushed motor should be 30-40 amp size so figure $100.00 for motor, gearbox and ESC.
Good Luck!
Ron

[sparky flyer]

50+

If yours is the 50" wing span version, a 6V Speed 400 geared 2 or 2.5 to 1 and 7 or 8 1100 mah cells should be power enough to fly it.

I have one of these in the box for a future project.

Steve

[50+AirYears]

It is a 50" span silk covered plane. I was almost considering the gear drive from my dearly departed Kyosho Cardinal. The day I recived a reverse timed Magnetic Mayhem was the day a wind gust got under the wing during launch. Great flying for the last 12 years.

[Sky Sharkster]

To 50+, It sounds like Steve has the same plane, or a modern version of it. Since I haven't seen it, I'd go with his advice for a geared 400. That is, if the plane is in the 20 ounce range. It may be that the silk-covered version is heavier. If it's getting up near 30 oz RTF you might be needing more thrust. The magnetic Mayhem would be OK in that case. You won't get as long a run as a 400 but I spend a lot of time gliding my OT's anyway! Moto Calc would still be a good place to start either way.
Ron

[sparky flyer]

Sky sharkster has a point. The all up weight for a Speed 400 would need to be in the 20-30 oz range. I think before I used a Mag Mayhem(heavy), I would go for a small brushless in the 100-120 watt range.

Steve

[Gonnacrash]

Hi gang,
I have a Sportster with HP .15 on it. I've never flown it and probably won't ! I'm like 50+Years, on the insurance, deductable etc. Inflation
sure nailed my check only with deflation !
Anyone interested in the AirTrails shoot me an e-mail for pics and etc info.
Gonnacrash@sunflower.com
Thanks,
Don-Basehor, Ks

[William L Baker]

Flying old timers with electric is currently (no pun) my main thing. I converted very sucessfuly from glow a 84" powerhouse, my favorite flyer now, and a 72" Scientific Mercury. Also a Kloud King, about 64 " span. They are pleasant and easy to fly, will thermal, easier to see at altitude than a sailplane with high AR wings, and make great touch and goes. Best source for kits are the partial kits from Klarich, and Bob Holman/Jim O'Reilly. These are plans and laser cut ribs and other cut out parts, no strip wood , no hardware. Also I find the designs intended for !/2A Texaco (.049 glow) make fine flying speed 400 powered models . I was oldtimer columnist for Model Aviation for about 13 years. Glad to help if I can. I am presently working on a Kloud King scaled to 84". I also converted to electric a Senior Telemaster, just to show the club it could be done. With Axi motors and lithium batteries, the conversions fly better than they did with glow.

[E-Challenged]

Using a Speed 400 motor in a gearbox requires special techniques and equipment to install pinion gear onto motor shaft. Basically you have to find a way to press the gear onto the shaft in a vise or a press while supporting the other end so as not to damage the motor. If you can do that the rest is easy. I like the Mini-Olympus 2.3:1 gearbox made for Speed 400 6 volt or 7.2 volt motors. It growls like a an opposed 4-cylinder engine. A Graupner 9x5 "slim prop" with spacer for the Mini-Olympus prop shaft works well. Use the 6 volt motor with 7 Nimh cells or 7.2 volt motor for 8 1100mah NiMh cells. You will need a brush type speed control rated for around 14 amps. Modern speed controls have a battery eliminator circuit to power your motor, receiver and servos without a separate battery. Hobby Lobby sells good Jeti brand brush type speed controls . Hitec HS-55 servos should work for rudder and elevator. You can get all of the above from Hobby Lobby by phone or online. A lot of guys have converted from round cells to lipos and will sell cheap or give away their old brushed motors, speed controls and battery packs., ask around the flying field.

[William L Baker]

I use a drill press. If the motor has a bit of shaft exiting the read, make a home in a block of wood for the rear shaft to go, adjust the jaws of the drill press to fit over the output shaft Hold the pinon gear on the shaft and lower the dril press to contact the gear. The jaws should just fit over the shaft and contact the gear. Apply pressures slowly but firmly to push on the gear,.

[Randy W.]

Saw Addie Nagatto fly a 108" Dalaire Sportster with a speed 400 and a big gearbox! Im sure the model was built light, but is flew great. She is a master!

[Eric_N57105]

Sky sharkster has a point. The all up weight for a Speed 400 would need to be in the 20-30 oz range. I think before I used a Mag Mayhem(heavy), I would go for a small brushless in the 100-120 watt range.

Steve

I flew my Hobby Lobby Miss2 with a 400XT direct drive brushless ($18). Miss2 has a 54" polyhedral wing, weighs around 22 oz AUW and has no problem with ROGrass, big pretty inside loops, unbelievably sloppy barrel rolls, death-defying inverted, but mostly it just putt-putts around the sky with no purpose. It pulls about 10 amps with a 10x4.7.

I recently replaced the 400XT with a Scorpion 2212-26 to check out the motor. It has more power (150W), but it isn't really needed or very useable for this plane.

A 400XT, 12-15A ESC and 3s 1320 lipo gives you more than sufficient power for probably less than $80 with careful buying.

[50+AirYears]

One of the considerations I have is the Sportster has a very short nose moment, so if I were to use an electric package that was too light, I'd have to add a significant amount of additional dead weight under the motor for balance. Any motor I use would need to approximate the weight of a Fox .19. Someday, I need to weigh the darn thing!

The late builder was one of those guys who believed in epoxy for strength.

This is basically my 7th Old Timer. It's also about the only one I haven't flown with timed engine run or fuel limit. The Futaba .6 ounce servos didn't seem to have the rotary range to give me full throttle, but the plane gets off the ground into a 45 degree climb at about the 2/3 max throttle I had set up.

BTW, in another improvement, those $400 meds are now approaching $500. That's in spite of my quack letting me change one to a $18 generic.

Thanks for all the suggestions.

So many planes; so little time.

[pd1]

I don't know if this will help.

I have a new brushed 480 that came with an E-flite P-47.

If you have a controller, you can have it.

It won't be as heavy as a Fox 19, but it might work.
What's the all up weight of the plane?

Paul

[50+AirYears]

Someday, I'll have to weigh it. It feels kind of heavy for it's size. The original builder was one of those who used a LOT of epoxy and very little sandpaper. I'm currently in the process of trying to attrite aircraft through the natural means of placing them into their natural element and allowing the nature of flight to follow it's natural course so I'll have room to reduce my supply of kits and raw balsa by transforming them into living flying machines. Restoration of the deletorious effects of hangar rash has taken second stage.

That .19 was totally adequate for the plane at 2/3 throttle for take-offs and mild aerobatics.