Graupner Prop Rotation Confusion
- Thread starter rocjock
- Start date
and THAT ladies and gentlemen is why they paint a big L on the prop! end of story...
helloman1976
Ziptie Relocation Expert
If the package determined the way the blade spins, you'd be right LOL. I think it's hilarious that people are focused on the printing on the label instead of the raised portion of the leading edge. This is getting ridiculous and again it's not up for discussion. It's like saying birds fly backwards because they're labeled that way or cars drive in reverse because they have an R on the stick.
Clockwise cleared up by science not by Chinese labels LOl
Circular motion can occur in two possible directions. A clockwise (typically abbreviated as CW) motion is one that proceeds in the same direction as a clock's hands: from the top to the right, then down and then to the left, and back up to the top. The opposite sense of rotation or revolution is (in Commonwealth English) anticlockwise (ACW), or (in North American English) counterclockwise (CCW). In a mathematical sense, a circle defined parametrically in a positive Cartesian plane by the equations x = cos t and y = sin t is traced counterclockwise as t increases in value.
Definition of CLOCKWISE
: in the direction in which the hands of a clock rotate as viewed from in front or as if standing on a clock face
— clockwise adjective
Wikipeida
http://en.wikipedia.org/wiki/Clockwise
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What about this one? It's not an "L" prop but it spins CCW if viewed from above.
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helloman1976
Ziptie Relocation Expert
Ah yes, the package...LOL I'm seriously done with this thread. Don't even bother, I'm not responding to any more of this ignorance. Clocks spin clockwise, if the blade produces lift by spinning clockwise then it's a clockwise blade that's all I'm going to say....I'm done.
Not if the disk is on a horizontal plane. That's why I was confused. It was just my ignorance in assuming it was labeled as if on a horizontal plane - like a heli.
Well that's good for everyone.
Back to the subject. You can see that they are all marked this way and the OP's prop was not mislabeled. It has to do with the viewing orientation that the manufacturer uses. In this case Graupner is using the same methodology full scale aviation uses. CCW when viewed from behind. Confusing as heck that's for sure if you're using these props on a multi. Not so much on an airplane.
Anybody have some inside skinny about Graupners? I have them for my first build and want to know if I should get more now. While I can. I hope they're not extinct already.
Update:
Today I checked the source of my Graupners and they are now out of stock. It was one of the last dealers which had any at all.
I must have received the last batch in the world. Thank goodness I have 2 spares.
Graupner propellors are gone.
Time to look at other makes.
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I'm new to multi-rotor craft and I must say I read this with considerable amusement. The entire issue is simply a matter of which direction, above or below, one views the spinning prop! Any prop spins to do its "work" with the raised leading edges leading the way - that's obvious - but whether it spins "clockwise" or "counterclockwise" depends entirely on what direction you are viewing it from!
For instance, on a quad, if it's flying above you the props that are spinning "clockwise" are spinning "counterclockwise" when viewing it from above as it sits on the ground spinning its props getting ready to take off. Same two props, each spinning in the same direction, are clockwise when viewed from above, counterclockwise when viewed from below. Vice-versa with the other two props. Like the earth which spins counterclockwise when viewed from the north pole, clockwise when viewed from the south pole.
For instance, on a quad, if it's flying above you the props that are spinning "clockwise" are spinning "counterclockwise" when viewing it from above as it sits on the ground spinning its props getting ready to take off. Same two props, each spinning in the same direction, are clockwise when viewed from above, counterclockwise when viewed from below. Vice-versa with the other two props. Like the earth which spins counterclockwise when viewed from the north pole, clockwise when viewed from the south pole.
This whole problem, which people seem to be able to get passionate about, arises because of the unfortunate use of the words "clockwise"(CW) and "anticlockwise" (or counterclockwise CCW). There are two types of screw or propeller. Each is a mirror image of the other. Unfortunately, in trying to describe them as CW and CCW, we need to adopt a convention, because whether something is spinning clockwise or counterclockwise depends entirely on the point of view of the observer. To resolve this, from time immemorial the convention has been adopted that we will describe the prop from the point of view of the pilot in the cockpit of an aircraft with a tractor propeller, i.e. what direction she/he would describe the rotation as she/he looks forward at the spinning prop.
Boat people adopt the same convention, except they are likely to say "right" for CW and "left" for CCW. I think they are smart to do this, because it avoids the CW/CCW confusion, and instead recognises that there are exactly two types of propeller, and "left" and "right" are as good names for them as any.
Unfortunately, most of us are usually looking down on our multirotors when they are stationary on a bench and we are about to fit the prop, so what we see is the OPPOSITE of what the pilot referred to above sees. However, we would be inviting confusion if we adopted a different naming convention from the rest of the world, so we've got to live with it. Graupner is correct.
Boat people adopt the same convention, except they are likely to say "right" for CW and "left" for CCW. I think they are smart to do this, because it avoids the CW/CCW confusion, and instead recognises that there are exactly two types of propeller, and "left" and "right" are as good names for them as any.
Unfortunately, most of us are usually looking down on our multirotors when they are stationary on a bench and we are about to fit the prop, so what we see is the OPPOSITE of what the pilot referred to above sees. However, we would be inviting confusion if we adopted a different naming convention from the rest of the world, so we've got to live with it. Graupner is correct.
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What are you taking about. Doesn't matter if you're looking at the props from left, right, center or from the moon - if you're looking from above (which btw is the convention) then cw is clockwise and ccw is counter clockwise. I don't understand where the confusion is.
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OK. You break a prop, so you have to order a replacement. Using your argument, you order a CW prop, because that's what it looks like to you, viewing it from above, which btw is NOT the convention. The wrong prop arrives, because you have used a convention opposite to the rest of the world.
Can you please post an image from any manual for any flight controller in any language where the supported motor mix images are not represented from a top view.
When was the last time you looked at a watch or clock from behind and said that it was going anti clockwise.
I understand your comments regarding left and right - but this does only apply to the pilots view and refers to the nose of the craft as viewed from ABOVE. So left and right change with perspective, eg when looking nose in our tail in.
The direction of a rotating clock is ALWAYS the same (except in some novelty clocks), doesn't matter if you write left to right or right to left or even top to bottom, whether you're in the northern, Southern Eastern or western hemisphere, clocks rotate clockwise. Please enlighten me as to where this is NOT the convention.
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I am talking about the convention for the way the propellers are named (being the issue in this thread), not the definition of clockwise or the convention for how motor mix images are represented. Look closely at one of the manual images you are referring to. The propellers they show rotating clockwise are counterclockwise propellers, and vice versa. This is where the confusion arises.
Have a look at the attached photo, quad viewed from above. Focus on the top right orange prop. I think you will have to agree, that prop would have to rotate CW for the quad to lift off. Ask any pilot what sort of prop it is, and he will tell you it is CCW. So will Graupner and all the other suppliers.
There were aircraft and boats long before there were multirotors. They set this convention, and whether we like it or not, we are stuck with it.
If you don't agree, all I can suggest is that you always buy props in pairs, or that you send the broken prop to the supplier for matching. Otherwise you are going to be disappointed.
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Take the prop out the side with the writing is the up side. Then the part with the bump should be the leading edge the pointy end is the trailing edge meaning the leading edge cuts into the air the trailing is the back end of the prop so it spins that way. That's how I tell them apart quickly.