ScalAuto MRRC SC004 (NC2 clone) is rubbish!

[djini_hades]

OK, can anyone give me any advise on my experience of these motors?

The motor in question is the ScaleAuto (SC004).
The manf. state the following specifications:
SC004 29000RPM 360g/cm torque.

I have had experience of 3 of these now, and they are all sub-standard. I had intended to use these motors to replace 'standard' Ninco NC2's whose spec are by way of comparison:
18100RPM 263g/cm torque.

I do not have a kelvin lightbench or anything scientific like that, but the performance of these scaleauto motors was *so* terrible (Both RPM and Torque but ESPECIALLY torque) that is was visually obvious that not only are these motors not running to the spec, they were not even running to the same level as the Ninco NC2's.

Some further info. The motors were put into Ninco F1 cars (Arrows), with the standard magnet, + 1 smaller magnet next to it. The motors, bearings, crown, pinion and braids had been treated with ZX1 oil/friction inhibitor (Both motors treated the same). The wires were soldered by an electrician friend of mine with about 10 years experience in wiring, soldering etc, these had also been monitored for resistance and the draw was pretty much equal.

The track (that these have been tested on) was a 'commercial' 6 lane 110' plastic with variable voltage (12v -->18v) of 'medium speed' with 1 long (30'?) straight.

Finally. If I was comparing these motors to something else (and bare in mind the *expected* rpm and Torque) I would have put them in the NC1 league (15000PRM, 74g/cm torque)...

Oh and they have been run in for about 30 mins (Free and under load) but not made too hot.

So, in summary, does everyone else think these can's blow goats, or can someone tell me how they should be 'run in' or something?

C (Of London Scalextric Club (Wood Green))...

PS: Big shout-out to Tony for pulling a 20 lap in his SCX Monster last night!:) :)

[orangepicker]

they are supposedly to be a good replacement for the nc2's
i used them before but they went to the rubbish bin after 3 hrs of testing and running.

these motors are made with for torque not for speed.
since you are using a plastic track,try a rabbit or a foxII motor.
i 'll say you'll have a good time on your hands without so much modifications.

i fitted a cheetah (old style) in my ninco clk. the wheels and bearings gave way due to the speed of the motor,and i was using the same gear ratio from the boxstock form it came with.

torquey motors like bison,carrera ,scaleauto and the buhler type motors need bigger pinions.
try a slot-it 11 pinion and see if its going to work.

cheers.

[djini_hades]

I chose the more torquey motor so I could put more magnet in it and not burn the motor out in the 2min 30sec race... I didn't even get the chance to add more magnet... they never performed well enough!

I've read so many positive things about these motors and how much power they have... It's just baffling how the motors I'm getting can perform so badly...

Could it be a bad batch? Or the stockest keeping them too close to some weird magnetic field thus killing the magnets or is my burn-in process need examining (I've been told to run the motor for 10 mins IN WATER? WTF?!?!?!)... What should I do to prepare a motor?

Any advise PLEASE!!! Also, why did they end up in the bin after 3 hours? Did you burn it out or could you not get them to work well (Like I'm experiencing)...

Rabbits and such are not an option (banned motors because they are too quick?)... as are 'group' motors...

[GearBear]

Yes I would break int all motors under water. This helps lubricate the brushes on the comm and virtually stops the arcing of the brushes during a break in period. I don't think I would do it for 10 minutes though! After breaking in the motor under water clean it up with lighter fluid and spray it dry with compressed air. The oil it up and put it in the car. For more information on this search Monty's forum for water breakin procedures.

Next I would try changing your gear ratios around until you find the best fit for the track/motor combination. This will be mostly trial and error as each track/motor will be different. For instance, you may find that these motors like an extra tooth on the pinion as they should have more torque than stock. This may actually make the car less drivable though and perhaps you will find you want one less tooth on the pinion. Test Test Test.

I can't give you specifics on the motors in question as I don't have any of them.

[Foamy]

>>I've been told to run the motor for 10 mins IN WATER? WTF?!?!?!<<
10 minutes in water, you probably have no brushes left.
Do it for about 30 seconds, blow out with compressed air, oil and run in car.

[djini_hades]

Thanks for the tip Foamy... I'll be sure to run it for <30secs!

...But I still want to know... are these motors under spec or not? Does *everyone* who buys them have to water-prep them? Seems a little strange to me...

Can someone tell me their experience with these motors?

...and please, enough with the gearing suggestions!!! I get that bit :)

[Larry LS]

The motor you are talking about is one of the many cheap motors made out there for folks to be able to buy them cheap, they are are probably only within 10-15 % of tolerance, if that. Some are great, others are junk, thats why they are cheap.

No you don't have to break them in, in water, the maker sure does not. It does help to seat what little brushes they have to the round commutator inside.

They come with only two small areas of the brush touching when you get them. They break in as most people run them.

Some like to pre seat those brushes in water as it helps break down the carbon a bit faster and hones the brush a bit to fit the comm better. If you do it too long, the brush will quickly wear away.

Then you lose life span of the motor. While running in water use no more than 4 volts to not over do it. While in the water you will see the dark brush material being washed away by the spinning action.

These motors you mention are by a new maker and not many people have any experience with them but they appear to be a typical cheapo motor. Like the rest. You get what you pay for.

The picture below shows some of these cheap arms and endbells, you can see as these are all brand new how little contact area there is with these cheap brushes. The two dark circles on each copper surface is all the contact they make when you get them new. Thats why breaking them in a bit first ,increases the contact area for more power and smoother running.

So have some fun and try something else for a motor if not happy with these.

http://webpages.charter.net/lshep1106/armbell.jpg

[djini_hades]

Thanks Larry....

I'll be trying the 'wet motor' to see if it works...

In the meantime, I'm pissed off guessing motor rpm and ability to accelerate, so I'm getting a friend to write some software to measure the moment of the mouse (The rollers inside), then basically gutting out a mouse then using the mouse rollers to get telemetry off the motors to measure RPM etc...

Hope that all makes sense>>>???

Hey presto, a cheap dyno :)

:p