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tomjkear

First Car Built - Df-03 Dark Impact - Got Questions!

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Hi Everyone,

I have spent some time looking about this site and it looks like there is a lot of interesting content, and also some very knowledgable people.

I have recently completed the build of my Dark Impact DF-03 car and all went well. I do, however, have a few questions.

The car seems to pull to the right a little when moving forwards, fast or slow, and pulls to the right when I reverse. I have tried changing a few settings but can't seem to get it to run straight. Can anyone advise?

Also, the motor makes a strange high pitched sound for some reason, is this normal? It's more noticable in reverse, because the car is going more slowly, but is happening in forwards too.

Finally, what sort of range should I be expecting with the car? I am using a Futaba 2PL Radio and I'm convinced the signal weekens and the car is less responsive even at a fairly short distance.

Any guidance would be much appreciated.

Regards,

Tom Kear

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The noise is probably the pinion mesh, Too tight. I use a piece of paper,folded to set my mesh.

I push the pinion flush against the spur gear, Then take a stip of paper folded over double, and feed it between the two gears, turning the spur with my finger to wind it through, Then I nip up the screws holding the motor, extract the paper and the job is done.

Range?...further then you can see the car to drive it :) Ensure the batteries in the transmitter are fresh, and that the reciever wire in the car is seperate from teh rest, Don't coil it in the car either, Pull her all out the top of the mast and coil it up there, If its real long I wind it down around the mast.

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The noise is probably the pinion mesh, Too tight. I use a piece of paper,folded to set my mesh.

I push the pinion flush against the spur gear, Then take a stip of paper folded over double, and feed it between the two gears, turning the spur with my finger to wind it through, Then I nip up the screws holding the motor, extract the paper and the job is done.

Range?...further then you can see the car to drive it :) Ensure the batteries in the transmitter are fresh, and that the reciever wire in the car is seperate from teh rest, Don't coil it in the car either, Pull her all out the top of the mast and coil it up there, If its real long I wind it down around the mast.

Yeah i would agree with the mesh being too tight, this usually doesnt only make a strange noise but somewhat slows the car i found. As said before make sure you hold the motor tight when doing the final tightening of the screws because it slips ever so slightly always meshing tightly if not.

Im assuming you have tried trimming the car and have the lengths and positions of the steering rods are per the manual? I found the df-03 goes very straight forward but always zig zags at high speed reverse.

Mark

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Thanks for the information, I'm sure it will help me solve the problem. Just I'm not sure what the pieces are that you describe :)

Which is the pinion and which is the spur gear?

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Thanks for the information, I'm sure it will help me solve the problem. Just I'm not sure what the pieces are that you describe :)

Which is the pinion and which is the spur gear?

Pinion gear is the small one on the motor, the spur gear is the one the pinion drives

Are you using an electronic speed controller?

If you are this could be the noise you're hearing

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Pinion gear is the small one on the motor, the spur gear is the one the pinion drives

Are you using an electronic speed controller?

If you are this could be the noise you're hearing

Thanks and yes I am using an electonic speed controller, Mtroniks Evo20.

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When you hooked up the electronics, did you center servo saver on the steering servo correctly before setting up the ESC? Are the steering arms lengths as per the manual? Just some questions... Rob

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The high pitched noise from the motor is perfectly normal, it's caused by the high frequency speed controller pulsing power to the motor and disappears when the motor is running at speed.

If the car is pulling to the right the steering isn't trimmed correctly. Check the lengths of all the steering linkages are correct according to the manual. Remove the servo saver from the servo, position the trim on the transmitter in the centre with the car switched on. Reattach the servo saver again in the correct position, adjusting the trim on the transmitter to straighten up the wheels. Drive the car away from you slowly and adjust the transmitter trim so the car runs straight.

If the buggy still won't run straight at speed check the shock absorbers and the upper suspension links are the correct length according to the manual and more importantly are the same length on each side.

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Hmm, I just ran a motor on an ESC and and a mechanical speed controller, exact same noise, Are you referring to witch craft?

Or just the normal sound of the motor spinning?, I cant see how the motor would give a **** about what the power passed through to get to her....

I would imagine the thread starter has mentioned the noise because its abnormal, rather then..well....normal.

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When you hooked up the electronics, did you center servo saver on the steering servo correctly before setting up the ESC? Are the steering arms lengths as per the manual? Just some questions... Rob

Yes I made sure the servo saver was attached with the servo in it's neutral position. I charged the batteries first and turned everything on to attach it. The steering arm lengths were as per the manual, but I have since changed them trying to get the car to run straight...should I put them back?

The high pitched noise from the motor is perfectly normal, it's caused by the high frequency speed controller pulsing power to the motor and disappears when the motor is running at speed.

If the car is pulling to the right the steering isn't trimmed correctly. Check the lengths of all the steering linkages are correct according to the manual. Remove the servo saver from the servo, position the trim on the transmitter in the centre with the car switched on. Reattach the servo saver again in the correct position, adjusting the trim on the transmitter to straighten up the wheels. Drive the car away from you slowly and adjust the transmitter trim so the car runs straight.

If the buggy still won't run straight at speed check the shock absorbers and the upper suspension links are the correct length according to the manual and more importantly are the same length on each side.

Thanks mate, will work my way around the car again and confirm all the above.

Hmm, I just ran a motor on an ESC and and a mechanical speed controller, exact same noise, Are you referring to witch craft?

Or just the normal sound of the motor spinning?, I cant see how the motor would give a **** about what the power passed through to get to her....

I would imagine the thread starter has mentioned the noise because its abnormal, rather then..well....normal.

I don't know what is a normal sound for the motor to be making. This is the first time I have heard it :)

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Yes I made sure the servo saver was attached with the servo in it's neutral position. I charged the batteries first and turned everything on to attach it. The steering arm lengths were as per the manual, but I have since changed them trying to get the car to run straight...should I put them back?

Thanks mate, will work my way around the car again and confirm all the above.

I don't know what is a normal sound for the motor to be making. This is the first time I have heard it :)

The noise is a high-pitched whine, as terrysc said it is normal and it's the electronic speedo(esc)

Some esc's make more noise than others, the MTroniks being one of them

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Yes I made sure the servo saver was attached with the servo in it's neutral position. I charged the batteries first and turned everything on to attach it. The steering arm lengths were as per the manual, but I have since changed them trying to get the car to run straight...should I put them back?

the left & right tierods to the steering knuckles must be equal. If you adjust one side, do same to the other.

If your car doesn't track straight... adjust the rod between servo & the bellcranks.

It is best for a 90deg angle between the servohorn & the rod, not 90deg to the servo's casing.

My DF03 tracks nicely, but i'm also running a hi-torque servosaver & turnbuckles.

Toe-out is near zero but doesn't make huge difference.

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The noise is a high-pitched whine, as terrysc said it is normal and it's the electronic speedo(esc)

Some esc's make more noise than others, the MTroniks being one of them

Are you suggesting the ESC itself emits a noise?

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Are you suggesting the ESC itself emits a noise?

Yes it does. This is normal.

If, however, the pinion & spur are meshed too tightly, it will also create a different roaring/whining noise. Make sure there is at least a tiny amount of play between the pinion gear (on the motor) and the spur gear (large gear touching pinion). To check for the play (called backlash), you simply hold the pinion firmly, and turn the spur gear back & forth. The spur should have just a tiny bit of back & forth movement that is necessary for the gears to run properly.

The gears should mesh like this:

gear%20mesh%20close%20up.gif

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Yes it does. This is normal.

Righto, Mark me down as more then just a tad skeptical. Never heard an ESC make a noise in 20 years, Ands if I did hear one making a noise over and above the sound of the rest of the car I wouldn't use it, I'd return it or bin it.

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Righto, Mark me down as more then just a tad skeptical. Never heard an ESC make a noise in 20 years, Ands if I did hear one making a noise over and above the sound of the rest of the car I wouldn't use it, I'd return it or bin it.

Exactly, having experienced the DF-03 meshing issue personally i would say 90% that thats the noise being heard but starting the car some ESC's do make noises but usually barely audible ones and never heard over the motor and gear noises. Just hold the car off the ground and plonk your ear near the gears and all will be apparent.

BTW i love that gear meshing Gif, pretty cool.

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Thanks for all your input everyone.

I have tuned as recommended in this thread and all seems good.

I have used the trimming to stop the car pulling to one side.

It's not 100% but I am getting there with it.

The noise is without doubt the ESC.

I changed the gears meshing and it's running smother, but the sound hasn't changed.

It certainly sounds like it's the ESC anyway.

Does anyone know if this ESC is protected if the car goes out range? Will the car stop?

Also, what's the deal with charging? The battery gets too low to run the car but it's not empty by any means.

Am I OK to keep charging on top of what remains in there?

Thanks to everyone that has helped me thus far :)

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It's easy to tell whether a noise is the ESC or something in the drivetrain:

ESC noise is a constant fairly high pitch, and you will hear it as soon as the ESC comes on. If you just barely touch the throttle and creep the car forward, you'll hear it.

Gear noise will change with the speed of the car, and get higher-pitched as the car goes faster.

And yes, if the car won't move, the battery is discharged enough to charge.

I think some ESCs have a fail-safe if the car loses signal, but I wouldn't test it. Just make sure both antennas are in the air, your transmitter batteries are fresh, and you aren't driving under power lines or something that will cause glitches, and you can pretty much ignore radio range. You'll lose sight of the car before it runs out of range.

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Thanks for all your input everyone.

I have tuned as recommended in this thread and all seems good.

I have used the trimming to stop the car pulling to one side.

It's not 100% but I am getting there with it.

The noise is without doubt the ESC.

I changed the gears meshing and it's running smother, but the sound hasn't changed.

It certainly sounds like it's the ESC anyway.

Does anyone know if this ESC is protected if the car goes out range? Will the car stop?

Also, what's the deal with charging? The battery gets too low to run the car but it's not empty by any means.

Am I OK to keep charging on top of what remains in there?

Thanks to everyone that has helped me thus far :)

If your battery is a NIMH battery you can charge it at anytime you wish to top it off, if its a NICD then its advisable to flatten it all the way then charge it as they develop a memory effect and will shorten the life of your battery and its runtimes.

I have an RV15 and have never noticed a noise from the ESC so i cant say if this is normal or not but i have a duratrax that likes to sing to me, but never loud enough to hear it over the car.

Im not sure if all ESC's have failsafes for loss of signals but i believe all M.troniks ESC's do, this would prevent issues of it continuing when you go out of range.

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Does anyone know if this ESC is protected if the car goes out range? Will the car stop?

Unless it receives a signal from the radio the ESC will do nothing so the car will just stop.

Also, what's the deal with charging? The battery gets too low to run the car but it's not empty by any means.

Am I OK to keep charging on top of what remains in there?

Contrary to popular opinion NiMh batteries suffer from memory effect just like Nicads, just not as pronounced. The one thing you don't want to do with NiMhs is discharge them completely. Using a proper discharge tray the voltage will be taken down to no lower than 5.4 volts. If you aren't racing, so you just keep on driving until the battery won't run the car, then the battery will be discharged down to the same level and can be just recharged.

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Cool, thanks again for the information.

Hope I'm not irritating you guys with all the questions, I just have nobody else to ask.

I have noticed the servos seem to be getting interference in the house.

With the ariel extended I seem to be able to control the car, with it pushed inside the transmitter the car jumps about all over the place.

Could this be my wireless router for the internet that's causing the interference?

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Cool, thanks again for the information.

Hope I'm not irritating you guys with all the questions, I just have nobody else to ask.

I have noticed the servos seem to be getting interference in the house.

With the ariel extended I seem to be able to control the car, with it pushed inside the transmitter the car jumps about all over the place.

Could this be my wireless router for the internet that's causing the interference?

No worries about the questions. That's why we have this place...

The interference could be from your router. The easiest way to check background interference in a particular area is by simply switching the transmitter off. Then you can easily tell just how much radio interference is on your channel by watching how the car reacts to the background radio noise. Just be sure to hold the car securely with the wheels off the ground. Otherwise it could suddenly take off (or hurt you)...

You can always carry the car around your house looking for the source of the interference as well. Kinda a waste of time though since you won't be driving there anyways...

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No worries about the questions. That's why we have this place...

The interference could be from your router. The easiest way to check background interference in a particular area is by simply switching the transmitter off. Then you can easily tell just how much radio interference is on your channel by watching how the car reacts to the background radio noise. Just be sure to hold the car securely with the wheels off the ground. Otherwise it could suddenly take off (or hurt you)...

You can always carry the car around your house looking for the source of the interference as well. Kinda a waste of time though since you won't be driving there anyways...

With the transmitter turned off, the car does nothing.

With the transmitter turned on and with the ariel pushed in, the car does all sorts of eratic movements.

With the transmitter turned on and with the ariel pulled out, the car appears to be OK.

The reason I am concerned is because when running the car outside I'm curious how far the car can go away from me as at only a few meters I get the feeling it is less responsive.

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Cool, thanks again for the information.

Hope I'm not irritating you guys with all the questions, I just have nobody else to ask.

Irritating us, NO! Most of us like to show off how much we know about the hobby :D .

Keep the questions coming if you are not sure of something :unsure:

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With the transmitter turned off, the car does nothing.

With the transmitter turned on and with the ariel pushed in, the car does all sorts of eratic movements.

With the transmitter turned on and with the ariel pulled out, the car appears to be OK.

The reason I am concerned is because when running the car outside I'm curious how far the car can go away from me as at only a few meters I get the feeling it is less responsive.

Is the aerial the Transmitter antenna or the Recievers antenna (in buggy)??

Anyone, how long is a few meters? A block long? 100 feet?

The USA :unsure: should convert to the metric system like the rest of the WORLD!!

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