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Hi,

I just wondered if anyone knows what the difference in power is between the motors on the following scalex models:

I think these all have the same motor:
Silver Porsche 911 - C288
Gold Porsche 911 - C289
Triplex Rover - C283
PMG Rover - C280

Not sure what motor the bikes have:
Ducati '03 Capirossi MotoGP - C6008

I was asking because the MotoGP bike goes much faster than the cars do and I wondered if this was just down to the age of the motors in the old cars.
 

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Man made magnets do naturally loose their magnetism over time and if this has happened the motors will not be as powerful no matter how much current they draw.

However I have no experiance of this phenomenon in slot cars but I have known model trains from the 1950's and 1960's to have this issue and even Hornby trains form the 1970's. If the magnets are removable they can be remagnetised. This cannot be done with can motors.
Mod Note: Yes can motors ARE zappable- this is wrong!

If you live near a source of high voltage such as overhead cables or near a transformer this will have a detrimental effect on magnets.
Mod Note: Again, wrong - old wives tale!

If you store your cars near a TV then this is also a problem because of the fields generated.
Mod Note: Yet again, WRONG! Though could well be a problem for the TV.

Cheers
Moped

Mod Note: The Mod Notes have been inserted to ensure that no one is misled by completely incorrect (mis)information
 

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QUOTE Man made magnets do naturally loose their magnetism over time and if this has happened the motors will not be as powerful no matter how much current they draw

Never knew that magnets powered engines before.........

You learn something every day.
 

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Hi

????Moped?????

ALL magnets demagnise with time: Entropy.

TVs and Powerlines are not a factor.

Old magnets that are just lumps of iron magnetized do demag faster, however, we have been using ceramics since the early 60s.

but most mystifying was "If the magnets are removable they can be remagnetised. This cannot be done with can motors."

sorry, completely wrong. All can magnets are removeable and, at the commercial track level, using a "magblaster" to zap can and magnets is a common practice.

Prof.Fate
 

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QUOTE (phipster @ 21 Oct 2004, 07:28)QUOTE Man made magnets do naturally loose their magnetism over time and if this has happened the motors will not be as powerful no matter how much current they draw

Never knew that magnets powered engines before.........

You learn something every day.
<{POST_SNAPBACK}>


Unless I'm terribly mistaken, the armature breaks a magnetic field in order to produce electricity. So, all electric motors and all electrical power generation is, in essence, powered by magnets.

Have I got this wrong?


Mike
 

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Moped
QUOTE I have no experiance (sic) of this phenomenon in slot cars
In the light of that admitted inexperience, it would have been wiser to have refrained from posting altogether, rather than that mish-mash of misinformation!
 

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Back on topic:

The motors in the Rover and the Porsche as you rightly pointed out are the same; both cars were released during similar periods (1982) although the Porsche was initially released in 1978.

With reference to the facts and figures for each motor & techy bits etc. To be honest I really don't know; I would really like to know what the original Scalextric Mabuchi spec was, what revs these motors operated etc.

Also I think it is worth noting the condition of the motor should be taken into consideration, clear of dust, sufficient oiling, good connections, and decent braids before you really can a get a true measure of performance.

Some old Scalextric cars with the above preparation can still easily keep up with some cars of today and in some cases even go quicker.


Jamie

P.S. If you transplanted the MotoGP motor into a car, I think it would almost certainly be pretty rapid!
 

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case of 'a little bit of knowledge is a dangerous thing'?

Yes that is the theory, in practice the degradation of a motor (or even a weaker and more variable magnetism of a cassette tape) will not degrade sat on top of a telly for years.
 

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In technical terms the motors as fitted in the 80`s are like me....old and knackered! Not many turn like they used to, in my experience.
 

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Quote:

by heating the magnet or by exposing the magnet to external magnetic fields which oppose its field. Magnetized rock deposits (iron compounds like magnetite) have been found that record the Earth's magnetic field's history for at least a hundred million years, so this process is very slow

hi, Moped
I read your article and I can see where you got your ideas from. Just to clarify a little, the operative phrases were "which oppose its field" and "this process is very slow (hundred million years)". A magnet works because most of the little atoms in its rigid crystal structure are oriented the same way so they are all pulling in the same direction, and they can be disoriented by diffusion (heat, again...LOTS of heat, or lots of time) or by ambient fields, again over quite a long bit of time if the fields are weak (which they are in most cases). Also, the ambient fields in your home (tv, microwave (which is actually quite a bit more), the clock on your stove, the iron deposits in the mountain nearby etc) are all in different orientations and kind of balance each other out over time. And they also lose their field strength very quickly as you move away from them. Generally speaking, none of these effects is anywhere near as powerful as the magnetizer which originally oriented the magnetic material.

I appreciate the enthusiasm you have for information and slot cars in general, and you clearly have a creative mind. Personally, I would learn from the guys here who know about such things (notably Fate and Tropi in this case). They won't steer you wrong...except for fun


hang in there,
John
 

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Hi John

I accept what you are saying but as a result of my other interest (the dark side) where I am handling electric motors from the 1940's, 1950's and so on which have had magnets that have deteriorated and thus motors that just don't perform there have been past discussions about this with like minded individuals and we have spoken about these things. Whether the conclusions are accurate or not, it is up to the individual to make up their own mind.

I prefer not to store or place items that function through magnetic forces next to anything such as a speaker, or a cathode ray tube, that themselves use magnetic forces to function. Radios, TVs, Hi-Fi. Its all a hazard in my book for my toy motors.

As I have said, my mind has been made up on this and it is up to others to make up their own mind.

Cheers
Moped
 

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Russell Sheldon
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Most, if not all, magnets used in motors suitable for slot cars are of the sintered ferrite, or ceramic - whichever you prefer - type. In the 1960's, cast Alnico magnets were mostly used.

Cast magnets are manufactured by pouring a molten metal alloy into a mould and then further processing it through various heat-treat cycles. The resulting magnet has a dark gray exterior appearance. Sintered magnets are manufactured by compacting fine Alnico powder in a press, and then sintering the compacted powder into a solid magnet.

Ferrite magnets are sintered permanent magnets, composed of Barium or Strontium Ferrite. This class of magnets, aside from good resistance to demagnetisation, has the advantage of low cost and are the type used in mass produced motors such as the Mabuchi motors used by Scalextric.

Most of the very powerful "rare earth" or "Cobalt" types of magnets, as used in Eurosport "strap" motors, are a hybrid of casting and sintering but because of the many special steps involved in manufacturing they tend to be somewhat expensive. As with everything, you pay for performance!

All magnets are easily demagnetised if not handled with care. Special care should be taken to ensure that the magnets are not subjected to adverse repelling fields, since this could partially demagnetise the magnets.

Also, bear in mind that magnetic flux density (field strength) is affected by many external forces. Heat is not as serious as one might expect. Typically, a ferrite magnet will lose 3-5% of its strength by being elevated from room temperature to 100 decrees Celsius, the boiling point of water. When it cools, the strength returns to very near normal, so this is a reversible effect.

There is a point where a magnet will lose all of its strength, never to return until re-magnetised. This is called the "Curie temperature." For a ferrite magnet, this is somewhere around 450 degrees C, about 850 degrees Fahrenheit. Cobalt curies at about 800 degrees C.

The silent killer of magnets is called "contact demagnetisation." Every time you allow a magnet to stick to something, the magnet loses energy! The effect is not as serious on the poles as it is on the sides or ends. The worst possible way to package magnets is in a poly bag, stapled to a card where they are allowed to contact everything and stick together. Even sliding the magnets in the can will lose some flux density. By removing the armature, the flux path will be partially opened and the magnets will be weakened to a degree. Impact has an effect on the flux strength, but it really isn't significant.

If magnets are partially demagnetised, they may be easily re-magnetised, or "zapped".

Can the magnetic strength be increased through "zapping"?

With, for example, Mabuchi motor magnets, it is more an issue of "saturation". I have found that the magnets are mostly pretty much saturated, anyway. I've tried "zapping" them but there was no marked difference. When a magnet is saturated, it contains all of the magnetic field it can hold and will be as strong as it can and ever will be.

Kind regards

Russell
 

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Thanks for some top-flight info, chaps one and all, but I'm interested in one of the original points- how do the MotoGP motors stack up against the S type cans, etc- before I start to build another F1 chassis round one?
Any performance figures or practical experience? Particularly compared with the Beardog Mini or Carrera GO! type.
And....any tuning tips for the little beggars, Grah?
 

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Whoa... and I thought I just left my mechanics lecture....

Loads of useful info which, naturally, disproves any rubbish that may have been posted previously...

McLaren

PS. How many of you store you VHS (or BETA) video tapes within 2 or 3 feet of your telly?
 

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HI

What is the best method of storing chassis magnets ?

I'm guessing in a bundle in a special tray in the toolbox is the wrong answer.. ?

T
 

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I moved my Scaley GT40 in front on my PC screen and it left a streak of faint black mark on the screen. Which could be rubbed off the waving the car in front of it. The car didnt touch the screen to do this.
 

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QUOTE (subarumy98 @ 22 Oct 2004, 16:56)HI

What is the best method of storing chassis magnets ?

I'm guessing in a bundle in a special tray in the toolbox is the wrong answer.. ?

T
<{POST_SNAPBACK}>

I throw them in the bin...

McLaren
 
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