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helicopter ceiling fan...need some idea's

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My dad swung by today the shop today. Been trying to find a motor for this fan that he has been working on, and has been having problems finding one.

The fan is a set of helicopter blades, that are about 25' across. Figures the contraption weighs around 250lbs. He is wanting it to be around 4-5 rpm, and planning on just using a sprocket to gear it down to that.

He has 220v in the ceiling. Trying so stay under $1k if possible. I know next to nothing about electric motors, just trying to help him get the right stuff.

What should I be looking for motor wise for this thing?
 
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Only pic I have, and its an old one. Shaft is 1" or 1-1/4", dont remember off the top of my head
IMG_0770(1).jpg
 
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You'll need to look at gearmotors to get that slow. Standard small ac motor rpm is 1800 or 3600 depending on poles, so you'd need 360 or 720 to 1 reduction to get it down to 5rpm. With a 2 inch sprocket on an 1800 4 pole you'd need a 60 foot sprocket on the fan.
 
I would just copy what big ass fan does.
in-line planetary reducer with a vfd.
A better option might be to buy a macro aIr fan of similar size and modify to accept these blades.
 

This on a vfd and you can get your 7 rpm. It even has a 1 1/4” output shaft. Gonna be heavy as fuck though.

That one is configured for horizontal mounting...vertical shaft down would have the breather relocated, a different oil quantity to make sure the high speed pinion gets at least splash lubed, and likely dual shaft seals on the output shaft.

(signed, my previous job :laughing: )

Spent a bunch of time at both Macro Air and Big Ass Fan as a (potential) gearing vendor. You can find that same kind of gearbox with a flange mount instead of a foot mount (in the case of that one it would be an RF57 instead of R57) if that makes your mounting easier.

Cool project, I dig it :beer:
 
That one is configured for horizontal mounting...vertical shaft down would have the breather relocated, a different oil quantity to make sure the high speed pinion gets at least splash lubed, and likely dual shaft seals on the output shaft.

(signed, my previous job :laughing: )

Spent a bunch of time at both Macro Air and Big Ass Fan as a (potential) gearing vendor. You can find that same kind of gearbox with a flange mount instead of a foot mount (in the case of that one it would be an RF57 instead of R57) if that makes your mounting easier.

Cool project, I dig it :beer:
I wondered about lubrication issues of the drive pinions, running a bunch of oil is a solution but somewhat problematic if it's not exactly the right level.
 
I brought home a big ass fan motor, vfd assembly. The VFD took a dump. Been looking at ways to build blades, this looks like a good idea.
 
120v Gear motor and some pulleys or sprockets I'd bet would be fine.

I had one on a firewood bundle wrapper. It was maybe 40rpm. It had enough power to break an arm.
 
I'd use a 56c motor, 60:1 56c worm gear box, and do a belt final drive to knock it down to the proper rpm. 12" on blades, 2" on gearbox hits your target. Belt drive also is a slipper clutch so if not ramped down slowly with a vfd or power failure occurs it won't grenade the box or tear off the ceiling.

I'd want to to go faster though.
 
I'd use a 56c motor, 60:1 56c worm gear box, and do a belt final drive to knock it down to the proper rpm. 12" on blades, 2" on gearbox hits your target. Belt drive also is a slipper clutch so if not ramped down slowly with a vfd or power failure occurs it won't grenade the box or tear off the ceiling.

I'd want to to go faster though.
A 80:1 for $80 (max 0.08HP though):


Aaron Z
 
I vote dodge torque arm txt1 gearbox with a 4 to 1 reduction belt drive turning it. They are bomb proof boxes that can be used in any orientation. They are standard gear reduction so the blades can over run it without blowing it up like a worm gear.
I'd use a 56c motor, 60:1 56c worm gear box, and do a belt final drive to knock it down to the proper rpm. 12" on blades, 2" on gearbox hits your target. Belt drive also is a slipper clutch so if not ramped down slowly with a vfd or power failure occurs it won't grenade the box or tear off the ceiling.

I'd want to to go faster though.
 
I use an old snowblower chassis with a 1/4 hp motor to turn a 3'x9' trommel at 30 rpm, still has the speed control to go slower & faster.

Kinda big and unsightly for a ceiling fan application though.
 
Tough to tell from the picture, but I don't think the breather on that gearbox is where you want it to be for that orientation.

Cool install though, I dig it :smokin:
 
It looks like he figured it out but we had a grill rotisserie motor that turned incredibly slowly and would break your arm before it stopped.
 
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