Were you using Magnets?

Don't forget it's not all about the motor, extra weight means extra current and if he has a particularly good magnet that will also draw more current.

Could also be his controller

We need a little more information?

 

All true Colin, but.....if the guy excuses himself and says all he's done is putting in a lot of laps we know that's bull.
The more laps you put on a motor, the more the brushes will wear, the less amps a motor will pull.
Its the brand new ones that usually draw the most.
But before you start crucifying the guy..besides magnets there's also gearing, the amount of grip and how well he's set up his guide, braids and lead wires.
On the other hand..if I was the main supplier of motors for a competition....and I would match a batch of 20 motors out of lets say a pile of 30 motors I'd take out the 5 best and the 5 worst...and neather of those would end up in my car

But I'm sure you guys will come to an agreement..in a gentleman like way.

with kind regards
Tamar

 

13UO's are easily modified in ways that wouldn't be visible, the easiest is to replace the magnet's with modern neo type. Then you have stronger brush springs, different brush material and even a rewind or a dewind. All would make the motor pull more amps

Tony

 

Could be gears binding too...

The other question: is his car faster than the others?

Don

 

QUOTE (tamar.nelwan @ 8 Aug 2016, 14:24) <{POST_SNAPBACK}>The more laps you put on a motor, the more the brushes will wear, the less amps a motor will pull.
Its the brand new ones that usually draw the most.

New motors before the brushes bed in have higher resistance at the brush/commutator interface so as the brushes bed in the contact becomes more intimate/larger area and resistance slowly comes down thereby increasing current draw...

So that's the reason why club racers run motors in very carefully, me I don't do mine underwater like some but run a motor continually at just over the minimum voltage to get it to turn for at least a weekend

After bedding in then current ought to remain fairly constant until you get either brush wear issues or commutator carbon build up

 

The Series is very strict. No magnets, all the same chassis, body etc. the only difference is tire radii (due to sanding), color of the cars and how many LEDs they have. They all have t have 2 in front and 2 in back with a gold cap so that when they do night races they can see the cars.

So the only real difference is maybe 2-3 grams of weight and the tires... Neither of f which would explain 1 amp me of pull (I am guessing.., it is all voodoo to me)
And yes, he has been winning every race and by a margin of 1-2 seconds per lap.

 

QUOTE (dvd3500 @ 8 Aug 2016, 18:20) <{POST_SNAPBACK}>And yes, he has been winning every race and by a margin of 1-2 seconds per lap.

I smell a rat!

Wouldn't it be more fair to place all the motors in a bag and blind pick them? At least everyone can get the chance to have a go with this motor.

 

First, has the increased amp motor resulted in a faster car? If not it's probably a setup anomaly. If so then you have to decide if this person cheated. If he is innocent then I suspect Riko is right because broke in brushes with larger radiused area will pull more amps because each brush would spend more time shorting 2 poles together as the brush transits each comm segment gap. Having more "hours" on the motor or better still careful breakin would then give him essentially a better motor. There is also some evidence in my experience that the "gauss" of some magnets increases slightly with a long breakin. I assume this has something to do with running magnetic fields through them. I've measured this on RX motors and it's a real gain that also would show up as a small current increase. These are the only legal reasons I can think of that a motor might increase it's "amps" Now as was stated you can pick one out of many that is just built better and have a better motor to start with. But, if he's cheating there are a whole lot of things he could do.from aligning brush hoods to dewinding armature, to shimming magnets, to adjusting the timing and allot more, some of which has already been mentioned. It would take careful scrutiny to find some of these. The best thing, in my opinion, would be to handout motors just before racing so that racers don't have much of an opportunity to "tune" their motors. Also if you want you can make sure each motor gets to every racer so if cheating is occurring the juiced motor will go to someone else next race.

Just noticed a couple of post while I was typing that answer the first question.

 

Not enough info to make an educated guess but there is a simple answer in there somewhere.

-----

What Don asked "....faster than the others?"

How was the current measured? On track with load or power supply with no load?

Motors are 13D as in vintage 13OU Mabuchi? De-winding those is 'a piece of cake'.

-----

If the 'guy' handing out the motors is fastest you have a bigger problem than a VOM could ever show.

 

If his skilled tuning has greatly improved one motor it follows that he can repeat the performance gain in another.

So ask him to demonstrate his technique with a second, randomly selected motor.
Or, if the technique involves some 'trade secret' he would prefer not to share, with a motor which one of you has sealed to prevent disassembly.

That way he will be able to clear himself of all suspicions of untoward behaviour.

Michael

 

Ohm's law says V=IR

Now he could have had his finger on the trigger for more time and for a bigger pull and so more average voltage over the race and hence for a given resistance (assuming all motors to be the same) then more current drawn.

If the car is heavy then it takes more trigger pull and hence more current drawn. If the car has a binding axle then the trigger would have to be fully pulled nearly all the time and hence a very high current drain and if the car was stalled it would draw the maximum possible current... but it would definitely have trouble winning!

Assuming all cars have the same average voltage on track during a race then I = 1/R. More current implies less resistance.

Less resistance implies less losses in the windings and commutator. Less windings or thicker wire (and less winding by implicataion) means less resistance.

So, one checkable thing might be the motor's resistance. Put an ohmmeter on the braids and rotate the motor. Watch out for the minimum resistance. Compare with other motors.

 

You probably won't detect any of the comm advance "cheats" with an ohm meter. And if the 13uo is an SCX RX-4 style motor I could dewind up to possibly 30 turns depending on specific type and you would be hard pressed to find it except with an expensive meter. Adding thin strips of tape behind the magnets to decrease the air gap would also only be detectable with a complete teardown. Hell, if you're analog racing I can build a turbo mode into my controller using a stepup voltage converter easily hidden in the handle. This would give me, say, 18-20 volts of boost when everyone else is running at 12. There's many ways to cheat, some of which are almost impossible to detect. Handout motors right before the race is about the best you can do to prevent motor cheats.

 

Could someone post a picture of one of these "13D" motors in question?

RX-4? Is that a Mazda?

 

I am guessing it is a Plafit Motor FOX. That is what he sells in his shop.

So am I reading it right that it is possible that by simply running the motor a lot it can cause it to pull more amps?

The guy got a little grumpy when he was asked why his motors (in 2 different series) always seem to be pulling 1 more amp...

 

I wonder what the 'normal' lap time is. Some could no doubt claim that it's sheer skill that makes us go 1 or 2 seconds quicker than everyone else but has anyone else tried driving his cars? If the lap is 20 or 30 seconds then maybe 1 or 2 might seem reasonable but if it's only 10 or so, then it seems to be more than just skill at work.

 

Hi dvd3500
OK so the "13d" are you are talking about look like a Plafit Fox? (That's not to be confused with the much older 13UO motors some other contributors are taking about.)

Slot car manufacturer like Plafit don't usually make their own motors, the get them made by a specialist in electric motor manufacture. The motor factory makes them to whatever spec. the customer wants using as many of their standard parts as possible. Different specs often share the same pressings and moldings, the only differences are often the windings and perhaps the magnets or brush material, plus the label or printing that's put on the can.

That is why there are lots of different specs motors made in the same factory as the Plafit Fox. Put the wrong label on a motor and it's very difficult to see the difference. The difference in current draw between one spec and another can be well over 1 amp. The eagle eyed might be able to spot the different wire size, but quite small differences in wire diameter make a lot of difference to performance.

Do the motor makers ever get parts from a different batch mixed up? Quite possibly.
Does anybody ever swap labels or redo the printing to disguise their use of a different spec motor? Quite possibly.
Does anybody ever swap parts from different spec motor? Yes they do - if the rules permit it that's motor tuning - if the rules don't permit it that's cheating.

 

Let's not mess about HE'S CHEATING !, see how he likes an offer to buy his motor. Get the rest of the club members together and force a rule change, I.e hand out motors or anyone can buy anyone's motor for the cost of a new one.

Tony

 

Plafit Fox is an FK-130 not a 13uo. Everything I've ever seen that was called 13uo type had removable brushes and springs. The last production motor that fit that description were the SCX and similar RX series; even the RKs from SCX which are made by SUNTECH don't quite fit setup wise but sizewise they do.. The FK-130s have a few less ways to cheat and I don't ever remember getting one to pull an extra amp with just breakin but I could be wrong since I'm not as sharp as I used to be. Some of the FKs were made with the brushes misinstalled on the brush spring and were turned 90 degrees out in relation to the comm. on these motors you will get better performance with extra breakin because you have to make a whole new radius interface on the brush through running the motor in. You might get more current draw and more rpms with extra breakin in this case. It's almost impossible to open an FK and not leave some trace of tampering on the case. You can however go in through the cooling hole if the motor has one and fiddle with the timing which will increase performance and "amps". The easiest way to cheat would be to swap labels with a similar higher performance motor. I haven't been following what's available on the market now but I'm sure there's something very similar in appearance but different in performance. I agree with Tony. Chances are he's cheating and handout motors is the solution as he stated.
Jimmy

 

Scrutineering is a difficult issue

The event scrutineer should always be able to take a motor at the end of an event and strip it completely.
Signing up to the possibility of disassembly should be a condition of entry to an event and a competitor should consider it part of the cost of being a winner.
Unwrapping the armature, counting the winds, measuring the copper diameter and checking for evidence of illegal tampering is the only way.
"Legal or not" is down to your event rules and this MUST be clearly set down ahead of any event and enforced to the LETTER of the rules.
A scrutineer must apply the rules exactly as written not against some arbitrary after-the-fact interpretation of what was intended or not.

Unfortunately in slotting, there is no independent scrutiny. It seems to be another racer who does this, leading to a conflict of interest.
After all, if you have a secret (legal) car prep technique, you might not want to share it with the guy you just beat by a millisecond.
Being a scrutineer or committee member should give you no advantage on track but finding a way to make that happen is very difficult.

Scrutiny is such a touchy subject that in F1, no one who has been a scrutineer is allowed to join a team without a 2 year hiatus from the role.
(because of their knowledge of other team's cars)
One such recent attempt for an ex scrutineer "Charlie Whiting" to join a team was blocked by the FIA
http://atlasf1.autosport.com/2000/hun/gray.html

My own view is that mandatory post-factory retrofits are unhealthy for the hobby and do not meet the objective of making racing "fairer".
After all, which "Newbie" slotter would want spend 75 quid on a new car and then go to a club where you are forced to make en masse changes to inferior parts?

 

All very interesting discussion.

The motor looks the same as all the others and it is definitely a 13D Fox.

He did let other drivers look at the motor but there was no real opportunity to remove it or run tests. (the equipment is there but I think the guys protesting didn't want to get medieval on the guy because it is his series, that he created and he provides all the parts...)

The thing that got me was how prissy he got, speaking as if in a loop that all he does run the motors constantly more. He then went on to preach how in other series the difference is in 2-5 second span and so a 1-2 second advantage shouldn't bug anyone. He kept repeating "I have no secrets" which, of course, makes you think he has secrets because we are a paranoid race of creature

The idea of letting someone else race the car is a good one. Or at least use his chassis. The swapping motor bit may be an option as everyone strips the cars after each race anyway...

So apart from outright cheating, there is a technical, physical way to get more out of the motor that is visually the same simply by the tolerances of the various "bits" inside.

What I am thinking, this guy is a professional racer and has an online shop so maybe he goes through every motor and tests it and when he finds a good one he keeps it and the rest he sells....

While you can argue whether that is ethical real motorsport is no different methinks...

 

Curious... how was the current measured

 

QUOTE (dvd3500 @ 9 Aug 2016, 14:02) <{POST_SNAPBACK}>... He then went on to preach how in other series the difference is in 2-5 second span and so a 1-2 second advantage shouldn't bug anyone.
Am I understanding this right? He is claiming in other series the difference is 2-5 second per lap?
It would be interesting to know what series these are.
I'm used to racing where the difference between wining and not is quite often 2-5 second at the end of a whole 3 minute race.

 

nonfractal has a good point about setting down rules in advance. Indeed well organized slot racing events do just that.

Of course motors are free choice in quite a lot of events, but where there are motor restrictions the rules need to make these clear. Some rule do specifically say the organizers have the right to strip motors after the event in classes where the motors are restricted. Ideally organisers aim to do enough to stop cheating without spending unnecessarily long in scrutineering.

Unwinding the armature destroys the motor, that is not something to be undertaken lightly. Destroying a cheating motor may be a good thing, but destroying your entirely eligible motor just to confirm it did comply with the rules has its down sides! Non destructive alternatives such as measuring the inductance are sometimes used, (I'm told this gives more reliable detection of cheating than measuring resistance with at least some types of FK motors). A lot of FK motors don't have the winding glued on so unwrapping the armature and counting the winds is possible, this isn't possible on slightly more upmarket motors that have the windings bonded in place.

QUOTE (Jimmy in Greece @ 9 Aug 2016, 11:10) <{POST_SNAPBACK}>Plafit Fox is an FK-130 not a 13uo.
Indeed they are, but the original poster did say 13d not 13uo.
13d sometimes seems to be used as a generic name for FF-130 / FK-130 size motors - not sure what the origin of that is, I wonder if anyone knows a deeper explanation than 13D was a typo for 130?

 

Buy a motor from the guy and then ask for a replacement when it doesn't draw the same current as his standard motor.

Leo

 

QUOTE 300SLP said, "Indeed they are, but the original poster did say 13d not 13uo.
13d sometimes seems to be used as a generic name for FF-130 / FK-130 size motors - not sure what the origin of that is, I wonder if anyone knows a deeper explanation than 13D was a typo for 130?"

Philippe de Lespinay (Mr. TSRF) gives a good explanation as follows:
"Sorry fellows, but it is not at all like that. Indeed, the 16mm height designation would also applicable to the FT13UO, commonly called "13D". So that's not it. Things are indeed a bit simpler and lots more complicated.
Whatever the huge Mabuchi Company does today has little to do with its 1960's antics, when it was just a single factory on the outskirts of Tokyo.
In 1956, the Mabuchi KTK Co., or KMK depending on whichever Japano-English translation, began producting toy motors in a big way for the sprouting Japanese plastic model kit industry. These motors were named M1, M2 etc., then R3, R4... and the last of these motors was the R15 which is... the early Revell slot car motor found in the 1963 Ferrari 250GTO's in the racing sets. The early motors were dark blue with a gray end bell, but the R15 were mostly dark gray. The Eldon motors are R13 as an example.
In the middle of 1963, Mabuchi introduced 2 new motors especially designed for slot car racing use, the FT16 and FT36. These were so named because of a poor Japanese translation of "forward torque", meaning in fact, "clockwise rotating direction". The "16" denomination was such because it followed the R15, and the "36" designation was because, according to Ken Mabuchi, it was "3 times as big". Makes sense, right? sad.gif

The FT16 and FT36 were quickly followed by a smaller brother, the FT13UO, which was also their first can-side driven toy motor. Why 13 instead of 17? Because it was smaller than the FT16, "but not that small". But as the FT16 and FT36, the FT13UO did not have brush heat sinks and its end bell melted regularly in an acrid white smoke as soon as enogh heat was generated by the brushes. So after lots of complaints from the manufacturers warrantying all those motors, Mabuchi re-designed both end bells and cans and introduced the FT16D and FT36D motors, with large can bearing housings and brush heat sinks. The "D" designation was because there were several versions of the FT16 that used various armature and commutator designs. "D" was simply the 4th version in the line.
Later again, a "medium" size can was introduced, called the FT26D, just to fit in the line.
It really does not make much sense but this is how things were in a Japan unable to figure a proper translation for English, and that was very remote from the rest of the planet.
There is an interview of Ken Mabuchi dating from 1966 where he explains all this. One of my customers from Kobe sent me the copy of this with a translation for my new book.
So now, you know it all... and how much sense it makes, right?
Of course, nowadays, a "16D" motor is just a Parma lump made in China."

I go by this and assumed that 13D meant FT13UO which in turn is the term used generally, rightly or wrongly, for motors like the original 300 series Mabuchi, the Johnson 111, SCX RX-series, and other motors with similar endbell/brush configurations. I believe Mabushi originally used the designator FT-130 also so some of us old guys may use that from time to time though you probably won't find that reference on the Mabuchi web site any longer. Cheetahs, Foxes, TSRF, Little Ripper and a host of others are designated FK-130 Per Mabuchi web site. A picture when asking about motors would probablly be a good idea when asking about motors to avoid confusion. Jimmy