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Post by Admin on Dec 8, 2019 15:26:02 GMT -5
I have completed my first ARF, a Tower Hobbies SBach. I've used a Rimfire .32, and a HobbyWing 80AMP ESC, and a Motion RC (Admiral) RX600SP receiver. Everything appears to work so far, at least on the testing bench. I have gone through all the instruction manuals for every component repeatedly, checking to see if I have missed anything. Of concern to me is that I have the ESC properly hooked up. The prop spins clockwise if you're looking at the plane from the front. There is nothing in the Rimfire manual nor the ESC manual advising how to connect the motor wires (black, yellow and red) to the ESC wires which are black. Back during the summer I had prop rotating in a way that pushed the plane backwards on taxi - the result of attaching black motor wire to black ESC wires with no indicators as to what the proper connections were. I've only run the motor at very low power with a spinner on (props are always off inside) to test, so I can't tell if I've got it right. The ESC manual isn't helpful, nor is the Rimfire .32 manual.Is a clockwise (from the front) rotation correct?
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kevin
New Member
Posts: 5
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Post by kevin on Dec 10, 2019 19:05:38 GMT -5
I always consider the direction of rotation from the point of view looking at the shaft.
If you want to change the direction of rotation the motor is spinning you only need to swap 2 of the 3 leads between the motor and esc.
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don
New Member
Posts: 29
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Post by don on Dec 10, 2019 23:55:12 GMT -5
It should be counter clockwise when looking at your nut.
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Post by Admin on Dec 11, 2019 12:08:19 GMT -5
Kevin and Don
Thank you for your answers. One of the problems of reading through the rc forums sometimes is information overload. I had been reading the following post, and that's what got me thinking, and then confused.
A true electric pusher prop is a left-handed prop designed for normal clockwise rotation. In order to get the same efficiency using it as a puller prop you need to BOTH reverse the motors direction to CCW as well as flip the prop around on the motor shaft. "Counter rotating props" refers to a twin engine plane in which one puller/tractor prop is rotating CW and the other puller/tractor prop is rotating CCW. The two puller/tractor props are a mirror image of each other.
Originally props were designed to run counter-clockwise, viewing from the front of the ENGINE or MOTOR. This is because, until recently, model aircrafts were primarily powered by Internal Combustion engines with Counter-Clockwise(CCW) rotation. So in order to use gas IC CCW engines for pusher setup, special "Pusher props" are commercially manufactured with negative pitched(left-handed) prop blades, as compared to a conventional(right-handed) tractor prop blade. If you put both of them face-to-face to compare, the props are an identical mirror image of each other. In other words if you put your pusher prop in front of a mirror the image you see in the mirror is now a puller prop configuration.
A tractor prop on a gas IC engine turning CCW could also be considered a tractor prop on an electric motor rotating CW, but ONLY if the prop is flipped around on the motor shaft. In other words one is referred to as a left-handed prop and the other as a right-handed prop, Some twin engine planes use counter-rotating props both of which are a tractor or puller. One is a left-handed prop and the other a right-handed prop. So, it depends on the normal rotation of the power plant for its compatible prop as to whether it is called right-handed. A right-handed prop on an IC gas engine with normal CCW rotation, and a right-handed prop on an electric motor with normal CW rotation are actually a mirror image of each other. Yet they are both called a puller, tractor or right-handed because of the power plant's designed rotation for spinning the prop.
Since the last decade, electric models started to become very popular and one so-called advantage of them over IC engines is that they can be wired to rotate either clockwise or counter clockwise. This will also allow a conventional tractor prop to be setup for pusher configuration, by BOTH flipping the puller prop the other way around and now reversing the motor to a CCW rotation. So, you can turn a puller prop into a pusher prop and vica versa by BOTH flipping the prop the other way around and reversing the motors rotation.
Besides reversing the motor from CW to CCW you also need to flip the prop around to turn a pusher prop into a puller prop. A pusher prop is a mirror image of a puller/tractor prop. However, what is more important is using the recommended propeller design that is most efficient for your plane as well as your flying style (from slow flyer to glider to sport, racing or aerobatic).
Then I came across this post, and it all made sense.
Imagine a screw being driven into a piece of wood. The prop is nothing more than a screw drilling into the air with the blade pitches being like threads on a screw. Run the engine counter clockwise (from in front of the plane). Understanding how a screw works, you'll also be able to see that the prop isn't installed backward.
Thank you again. I've think I've learned a lot throughout this build. I guess I'll know just how much I've learned after the maiden flight.
TM
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