A really daft question

[Keat]

Which way should the engine rotate, when viewed from the front ?

I've just been watching a Utube video, and it looks like the one on the video goes clockwise.

I'm just wondering, if the wires are crossed on my starter, as the starter makes the engine run anticlockwise.

If I swap the wires around the engine will still run.. so it will run in either direction.. which is the correct way ?

[flytilbroke]

A Normal I/C engine when viewed from the front rotates anti-clockwise.

 I guess you are new to this? If you are, the best advixce you are likely to get is find a Model Flying club near to you, you wil learn more and it will prove cheaper and safer too.

cheers

[Ernie]

 Hi Keaton,

Anticlockwise...Most engines will only run in this direction, but a few can be reversed

ernie

[Keat]

I've been down to the local club twice.. but only really get a chance on Saturdays.

I bought the irvine 40 tutor last weekend, so missed the club meeting.

I have been charging the batteries, getting to grips with the transmitter, having a feel for starting her up in the garage, and generally getting excited about taking it down to the club this coming Saturday.

I joined this forum, to ask the questions, I would only get a chance to ask on a Saturday.. thus saving me lots of valuable, learning to fly time...if that makes sense. ??

Thanks for the info..

I'll have another daft question tomorrow ....... no doubt

[spanner]

Didnt someone say ' the only daft question is the one you dont ask'

[Keiran Arnold]

And that assumption is the mother of all cock ups

[birdy]

How many threads I wonder are called "A really daft question"?!

[Keat]

Maybe there are more novices on here than one would like to believe..

and I'm the latest..

Ahh....... to be young again

[M'lud]

Just to ask another daft ? which way does one wind a rubber powered Reg Ball

[Ernie]

Another daft question, what's a Reg ball?

Ernie

[Ernie]

Mon Dieu, now I'm completely lost    

[M'lud]

Good God I ll never live that one down ,although it was a real ?  Reg Ball

[M'lud]

This morning I awoke in low mood, Now  m laughing my socks off  . Well done mates   Reg Ball

[Former Member]

[This posting has been removed]

[Andy Gates]

I am not too sure of the wisdom of running a glow IC motor in a space like a garage.

Best to be outside where if the prop breaks, you are less likely to be hit by the ricoche of part of the prop or from falling paint from tins on shelves. I don't think the fumes would do you much good either even if they do smell good!

[Peter Miller]

Going back to the original question (and I know that this is considered a NO-NO by many on this forum)

It is possible that the video you saw had the effect of making it look as if the engine was running backwards. Ever noticed on old films how wagon wheels and train wheels often seem to be rotating backwards.

[Pat (rActive) Harbord]

ah, this is doppler effect (I think). Not so long ago you could watch this phenomenon on your turntable as you changed speed from 33 to 45rpm. I think persistence of vision comes into it as well. This is why rotor scoping works to give us animated films.

then again I could be completely wrong 

[Peter Miller]

I think in fact that it is due to the frame rate not quite matching the rotation sped. Going back to wagon wheels, they will often suddenyl rotate in the right direction as speed builds up or slows down.

Not that any of this matters in anyway.

[shades]

Hi keaton,

Yes the engine should run anti-clockwise when viewed from the front. Videos often make rotating objects appear if going round the wrong way or the wrong speed. I have an old BMFA nationals video with a helicopter flying, which has the rotor apparently totally static. Really weird. It is caused by the frame rate being a different speed to the object rotating. Like a strobe effect.

However, a glow motor can run in reverse. I have had this happen to me when starting by hand. It is not always obvious this has happened, apart from there is a distinct lack of power and the throttle doesn't repond too well. Mind you, if you tried to take off in that state, it would become very obvious, very quickly.

BTW, doppler effect is the action of sound getting louder and quieter as the noise source passes by, I believe.

shades.

[birdy]

Your eye sees about 21 frames a second, so if a propeller turns 20 full rotations in a second, it will seem to be going backward. TV though is differnet. If your TV were to run at 21 frames a second, it would seem to flicker, so her in the UK we have it about 28 fps, which is called PAL. The people across the pond have it about 35fps, which is called NCS of something, hence why we cant use their DVDs.Because of this a tv can make the picture look defferent to the naked eyes veiw.

This is probably all incorect!

birdy

[Former Member]

[This posting has been removed]

[Keat]

I found the offending video, he starts it with a chicken stick, and no matter how many times  I play it, it looks like he fires it up clockwise..

 http://www.youtube.com/watch?v=sqXNSt2IDjI&feature=related

[Tim Mackey]

He is starting it by bouncing the prop against compression - it then "bounces" back and fires up and runs.

IC model aero engines run anti clockwise as viewed from the front. 

[Phil Winks]

I think the doppler effect is more to do with the effect of a wave of any sort either bouncing of or emenating from a moving object its used to good effect in "doppler radar" to detrmine I belive the target speed without the need for two radars I believe your basically right eric think its the fact that as say a train approches the pattern of sound gets faster because the source has got closer since that particular part of the sound was last emenated making the pattern seem to get quicker I think  

[Pat (rActive) Harbord]

Yep, he's definately bouncing off compression

Dopler:

The Doppler effect (or Doppler shift), named after Christian Doppler, is the change in frequency and wavelength of a wave for an observer moving relative to the source of the waves. It is commonly heard when a vehicle sounding a siren approaches, passes and recedes from an observer. The received frequency is higher than the emitted frequency when the siren approaches, is equal to the emitted frequency as it passes the observer and is lower than the emitted frequency as it recedes from the observer.

For waves that propagate in a medium, such as sound waves, the velocity of the observer and of the source are relative to the medium in which the waves are transmitted. The total Doppler effect may therefore result from motion of the source, motion of the observer, or motion of the medium. Each of these effects is analyzed separately. For waves which do not require a medium, such as light or gravity in special relativity, only the relative difference in velocity between the observer and the source needs to be considered.

from Wikipedia (so treat with caution)

hence we hear "neeeeowwww" on low fast passes 

I visual phenominon I was refering to is as Birdy states,. Interesting to note that the eye sees all, it's just the brain that can only process about 20-25 frames per second. I think flies can process the data much quicker so compared to humans, see in slow motion.