OK, it has been a while since I posted here. Been enjoying my mQX outdoors as summer develops.

Over the weekend, I demonstrated RC aircraft at the 2012 Intelligent Ground Vehicle competition here in Rochester Hills, MI. Had fun flying the mQX around in the demo tent. I put the #16 camera on it and shot some video of some cool FPV robots Tardec has developed for the US Army. Watch one of them pick up a water bottle and put it in the trash. The tan one liked to charge the mQX, presumably to see how it would react

Robots at the 2012 Intelligent Ground Vehicle competition (4 min 19 sec)

Enjoy....

Paul

Hi Brandigan,

That's a really good idea for a quick/cheap raised landing gear. I also like the camera mount you made. Do you have any video from it to share? I was wondering if you get jello affect with that set up?

Hi All,

Does anyone know where to get CW motors these days? Even GONITROHOBBIES seems to be all out of them, and I am down to one working MQX until I find one.

Thanks,

ST

Originally Posted by Scootatrash

Hi All,

Does anyone know where to get CW motors these days? Even GONITROHOBBIES seems to be all out of them, and I am down to one working MQX until I find one.

Thanks,

ST

Hi
I have ordered from Here:
CW

or

CCW

I Think they located in Hong Kong, Shipment to my country was about 5$

Originally Posted by Scootatrash

That's a really good idea for a quick/cheap raised landing gear. I also like the camera mount you made. Do you have any video from it to share? I was wondering if you get jello affect with that set up?

No I don't get any jello as the mount is in the dead centre of the Blade and I've also mounted the camera by its dead centre, but I do get some vibration, so I plan to remake it slightly thicker, shorter and with no hinge, as the hinge just allowed me to work out the best angle to mount at.

No footage worth a lick - been constant rain since I made it - and I'm also waiting for a CW (rear left) motor that's incredibly lazy and may also account for some of the vibration.

Has anyone had any success (seen the point?) of balancing the props?

I was playing with fire, and got burned

One of the skids got caught in the grill. Luckily only the propellers and canopy needs replacing.

Quad on fire.wmv (1 min 14 sec)

Excuse the music, not my video.


Picture:

Man thats nasty

Originally Posted by Scootatrash

Hi All,

Does anyone know where to get CW motors these days? Even GONITROHOBBIES seems to be all out of them, and I am down to one working MQX until I find one.

Thanks,

ST

In a pinch, you can use a CCW motor and plug it in backwards. One of my CW motors is actually a backwards plugged CCW motor and it has lasted for several months with no issues. It runs and flies exactly the same..... lifts off absolutely vertically and is totally stable in flight.

Near as I can see, the major difference between a CW and a CCW motor is how the brushes are "timed" relative the magnets. A motor that is timed for the intended direction of rotation will run slightly more efficiently and with less brush arcing. It is easy to check the timing of a motor. Run it unloaded at fairly low speed in both directions at the same voltage and note the unloaded current. It should draw less current in the "correct" direction. Back when my mQX was new(er), I measured all four of my original motors and found that two were timed correctly (but not by much). One was timed neutral and one was actually timed backwards. From that I concluded that there wasn't enough difference between a CW and a CCW motor to make much difference in use. I can't guarantee this will always be the case...

Paul

exita, thanks for the links. I have a new CCW motor I think I will try as pgoelz suggests. $15 is a bit steep for one little motor.

pgoelz, thanks for the info. I'm gonna do it.

Originally Posted by pgoelz

...
Near as I can see, the major difference between a CW and a CCW motor is how the brushes are "timed" relative the magnets. A motor that is timed for the intended direction of rotation will run slightly more efficiently and with less brush arcing. ...

Related to the timing is that the brushes on some motors are angled to spin more easily in one direction than the other (pulling on a brush, as opposed to pushing on a brush). A picture is in post 1076 of this thread:
http://www.rcgroups.com/forums/showp...postcount=1076

But pgoelz and I believe others have mentioned (in this thread) running the motors "backwards" and having things work out.

A related option is to use a similar size "8mm" motor (like a Solo Pro main motor, etc.) as a (less expensive) substitute, but this will involve swapping the pinion gear as the mQx likes a pinion gear with more teeth.

Originally Posted by pgoelz

In a pinch, you can use a CCW motor and plug it in backwards. One of my CW motors is actually a backwards plugged CCW motor and it has lasted for several months with no issues. It runs and flies exactly the same..... lifts off absolutely vertically and is totally stable in flight.

Another data point:

I have tried using two CCW motors as CW motors, neither lasted more than 20 flights. Most of my CCW motors have lasted more than 100 flights when used correctly.

I fly my Qs very hard and crash often, your experience hopefully will be better than mine.

Originally Posted by flying-llama

Related to the timing is that the brushes on some motors are angled to spin more easily in one direction than the other (pulling on a brush, as opposed to pushing on a brush). A picture is in post 1076 of this thread:
http://www.rcgroups.com/forums/showp...postcount=1076

I have seen several references to the brushes being designed to work better in one direction and I have to say that I don't buy it. I doubt that it matters which end the support is on.... ie., whether the brush is "pushed" or "pulled". At the brush/comm interface, the brush is just a flat bar of metal in contact with the side of a cylinder. I don't think it matters which way the cylinder rotates. IMO, anyway.

I suspect the real issue is how well the brushes are timed. My CCW motor that has lasted a long time as a CW motor may well be either timed wrong or neutrally timed. I never bothered to measure it, I just installed it. CCW motors that do not last long as CW motors may well be correctly timed for their intended direction of rotation and therefore worse in reverse. The key may be that they are not consistently timed in the first place. My originals definitely were not.

I've kinda backed away from the issue because my one CW motor is doing OK as is the CCW motor used as a CW motor. I fly outdoors just about every time I go out and fly my planes, and that is harder on the motors than flying indoors was.

If motor failure is still an issue for some, maybe it would be a good idea to measure the timing for each motor and use them in their actual favored directions?

Paul

Originally Posted by pgoelz

I have seen several references to the brushes being designed to work better in one direction and I have to say that I don't buy it. I doubt that it matters which end the support is on.... ie., whether the brush is "pushed" or "pulled". At the brush/comm interface, the brush is just a flat bar of metal in contact with the side of a cylinder. I don't think it matters which way the cylinder rotates. IMO, anyway.
...

One guess: as the brush is "pushed" or "pulled", it bends slightly with time. With the "pull", the bending will tend to be so that the brush gets "pulled" towards the rotating part (maintaining contact over a longer period in the brush's life)..
With the "push", the bending will tend to be so that the brush gets "pushed" back and away from the rotating part (breaking contact earlier in the brush's life).

This effect may be small compared to other factors about the motor.

I apologize for my ignorance...

what type of solder should you use on the 4-in-1 control unit and mqx related electronics?

I have some 60/40 rosin-core solder, will that work?

thanks!

Originally Posted by beerassassin

I apologize for my ignorance...

what type of solder should you use on the 4-in-1 control unit and mqx related electronics?

I have some 60/40 rosin-core solder, will that work?
...

As far as I know:

if it has a "RoHS" marking (and it seems most electronics boards do these days), then lead-free solder was used to put it together.
Lead-free solder and leaded solder (like 60/40 rosin-core solder) are supposed to make an unusable mess when mixed, so it is best to use lead-free solder when dealing with an "RoHS" board (I have both types of solder).