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On the confessional thread, AKA, cheaters, the topic of sequencing (edit: make that re timing, my memory failed) came up. What is it? How do you do it? Why would you do it? Why is it a cheat? When isn't it a cheat?

Degresion into rewinds, dewinds and general motor advise welcome.
 

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VOA, this is a complicated subject and for proper understanding you will need to have a good grasp of the operational principles of 3-pole permanent magnet motors.

Surf to this link:

http://www.slick7.com/S7magnets.html

and scroll down to the topic entitled: "Commutator Timing and Magnets."

I feel it would be best if you ignored the other sections, as it is likely they will only serve to really confuse you. The section to which I am pointing you may also be above your level of knowledge, but it should help even if that is the case.

See if this info helps you to understand timing and then report back to this thread.

FWIW, timing is normally adjusted in modern slot car motors by buying another arm or motor with different timing. That is, unless you are doing rewinding or diddling with sealed motors when you aren't supposed to do so. Most commercial slot car arms these days are tied and epoxied, which makes it difficult, if not impossible, to adjust the timing on them.
 

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Discussion Starter · #3 ·
hey, cheater.

NOT ALL THAT HARD TO FOLLOW. OOPS! that pesky shift/control key.
So really, as far as 1/32, a thing of the past. Unless you are building some stuff for the fun of it.

Seems like the parts/build up cost curve is the old wives tail about what killed commercial track slotting in the USA. Folk with money and time and skill could make it miserable for the guy with a regular car, not much mechanical skill and not very deep pockets. He just got tired of having his ass kicked by Mr. Moneybags.

Seems like a good case for RTR classes. Everybody races, everybody can win. Everybody can afford a car.
 

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Not quite the question that Voa asked, Cheater, but something that occurred to me while reading that excellent link you gave-

In the old days, we used to be very concerned with the 'integrity of the magnetic field', so we used thick cans, can liners, stuff like that. Now there are 'strap motors', where all that has been dispensed with. The magnets just hang in the flimsiest, lightest frame possible to keep the bearings aligned.

So what changed? Or am I suffering from my usual misconceptionitis?
 

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VOA, I think the main currency of racing success is still knowledge and skill, as opposed to deep pockets. Sure, money can always buy someone else's knowledge and skill but the person who has the experience always has the edge in my view. When racers have both the money and skill, they're really hard to beat!

Howmet, I've never built a strap can, but I think the reasons these setups are so widely used today in the upper commercial classes have to do with the strength of modern magnets and the drive for lighter motor weight, which improves handling. A further consideration is that RPM is now more the goal than raw torque, at least in most road racing classes. I think it is correct to note that strap motors normally use higher-gauss magnets, like cobalts, as opposed to the lower-gaussing ceramic magnets typically used in can setups.

The drag racers still use thick, more enveloping cans because these do give higher torque numbers.
 

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I raced 1/24 nascar at the local raceway a few years ago , the motors were "stock"
Parma,s . As in full size so called stock or spec. racing classes we were allowed to "blueprint" the motors which involved trueing the com. , aligning the brush guides and timing by twisting the com on the shaft . I even have a little tool which slips onto the com. maiking it easier and more accurate when twisting .
How far would you get in a grass roots racing class such as Formula Ford with an engine straight from Ford ?

Richard
 

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Richard, you are not incorrect, but almost all American-made arms are now epoxied and tied under the comms. Re-timing is not usually attempted with these arms, nor is it often successful. It is certainly still possible to re-time the (typically Chinese) unepoxied arms in the manner you state.

It bears mentioning that to re-time an arm, sufficient slack in the wires leading to the comm tabs is needed. It should also be noted that when re-timing was commonly done, it was a given that one would ruin a certain percentage of arms during the process, sometimes as much as 50%.

Since most raceways allow the use of American made arms in the builder-motor classes, re-timing is something that is now not very commonly performed, at least in my experience. And in the lower classes, spec motors, sealed motors like the Parma 501s and 502s, are the motors most often used, though there are methods for adjusting the timing in these motors without disassembling them.
 

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And, since this forum is mosly 1/32. The overwhelming majority of these motors have an awful brush set up where the tension is supplied by a bend in a brass strip holding the brush. When the motor goes away, it is usually that the temper of the brass strip has gone soft. Sigh. Then you throw them away.
On the major reasons "just take them out of the box and run them" is that the timeing on the commutator will vary by accident from Plus 5 to minu 5 degrees. AND THEN, the accidental timing on the brushes will vary Plus or minus 15 degrees! Worst case, stock out of the box you can have a motor that ought to be running BACKWARDS. Best case, by accident, you get a "hot" motor at Plus 15 degrees.

Sigh.

Fate
 

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I have noticed with the few motors I have played with that the brush,s are just "flapping in the wind" , some do not even have carbon contact,s .
The only traditional end bell I have is the SCX motor , but it also is the biggest motor .
It can only be a matter of time before some bright spark comes up with a traditional end bell for the mini motors . I have no interest in getting back into competition and only race for fun with my son , so all this is just theoretical for me ..

Richard
 

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One additional issue with timing you might want to ponder.

Most comms are manufactured as copper cylinders which are then cut or sliced to separate the three segments. My experience says that it is pretty rare for a comm to be sliced at exactly 120 degree intervals.

So any three pole arm actually has three timing figures, one for each segment. In an ideal world, these three numbers are the same. But it isn't an ideal world, is it?
 
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