# HO tjet magnet and armature Qs



## krazikev

I had writen down from years ago a list of the color magnets that work and work best with what color wound armatures (green/red/copper wire, xmas tree arms, ect.) can someone give me a link to the matchups please? thankyou


----------



## slotking

I would use dash mags for arms under 14ohms to make the most of them

Depending what you looking for dash mags for a 16ohm arm will provide more torque while the green & white t-jet mags provide more top end (and a lot less brake)

this not what you asked for
but I hope it helps
arms http://slotmonsters.com/slot-car-thunderjet-500-pancake-motor-armatures.ashx

mags http://slotmonsters.com/slot-car-pancake-motor-magnets.ashx

Note
it does not list the dash mags which are the strongest ceramic mags
you can also get poly mags

LOL
I wrote this hours ago
forgot to post it


----------



## krazikev

slotking said:


> I would use dash mags for arms under 14ohms to make the most of them
> 
> Depending what you looking for dash mags for a 16ohm arm will provide more torque while the green & white t-jet mags provide more top end (and a lot less brake)
> 
> this not what you asked for
> but I hope it helps
> arms http://slotmonsters.com/slot-car-thunderjet-500-pancake-motor-armatures.ashx
> 
> mags http://slotmonsters.com/slot-car-pancake-motor-magnets.ashx
> 
> Note
> it does not list the dash mags which are the strongest ceramic mags
> you can also get poly mags
> 
> LOL
> I wrote this hours ago
> forgot to post it


thanks for the reply, I have this link but cant understand why the tjet rating on the mags is listed as 1.5 2.0? I volt metered my tjet arms and they are all in the teens for ohms? please explain. also you metioned dash mags, what are those? sorry but I have been in this hobby for years but only in the collector side, I mean I know how to clean an put a chassis togther like cleaning bushes on paper and the old eraser cleaning on the 3 piece armature and things like that, but I am confused about the whole what mag to use with what arm. sorry but if you have time please detail me with a link or post the details of this whole theiry for me, thanks


----------



## alpink

*comparisons?*

" .... I have this link but cant understand why the tjet rating on the mags is listed as 1.5 2.0? I volt metered my tjet arms and they are all in the teens for ohms? please explain. ..."

the rating of magnets come in many forms and is only comparable within each specific persons type of rating/testing.

magnet strength should not be compared with armature OHMs of resistance.

DASH is a fellow named Dan (Lenny here) who is world famous for his perfect t-jet and AFX bodies. some are replicas of original t-jet, some are uniquely new.
he is currently assembling a replica t-jet chassis with newer technologies involved. the magnets he had developed and marketed before the chassis came to fruition are a little stronger than original Aurora AFX Super II magnets and a lot cheaper. in anticipation of the coming chassis he has also released t-jet type pickup shoes, some with a long step and some with a standard step.

have a gander here ....
http://www.hobbytalk.com/bbs1/showthread.php?p=4630775#post4630775 
....

more to come from many knowledgeable folks and remember, there is no stupid question. :wave:


----------



## slotking

al is right on the rating
what you see is the rating for the mags is a system the the writer decided to use.
the bigger numbers = stronger mags

I used a gauss meter to do my mags

so for example the site info of Rating: 1.5-2.2 = about 200 to 300 gauss on my meter while info of Rating: 4.5-4.7 of the super II mags had an gauss reading of about 900 on my meter.


----------



## slotcarman12078

Also keep in mind that magnets will lose some attractive power if stored incorrectly for long periods of time. They can also be zapped stronger if someone possesses the equipment to do so.


----------



## krazikev

slotcarman12078 said:


> Also keep in mind that magnets will lose some attractive power if stored incorrectly for long periods of time. They can also be zapped stronger if someone possesses the equipment to do so.


how should I store my mags? I just have them all stuck together in my tray, details please, thanks


----------



## alpink

a magnet zapper can return magnets to their original potential.
I have a top of the line Trik Trax ceramic magnet zapper.


----------



## Grandcheapskate

krazikev said:


> how should I store my mags? I just have them all stuck together in my tray, details please, thanks


I read they should be stored like this...

(((((((()))))))))

on a piece of metal. I use the backplate slot fillers from computer cases.

Joe


----------



## slotking

you have to keep the flux moving north to south.

for example
if you have a horseshoe magnet, they use a magnet keeper










the bar keeps the flux field moving from north to south

so if you do this
(((((((|)))))))

you will still need something ferrous to connect the 2 far ends

something like

|(((((((((((((((|
|___________|

and 1 for the opposite mag

Rare earth mags do not have the same problem


----------



## Jisp

I now realise that I'm guilty of storing my mags incorrectly..... ((((()))))

Soooo, who's right? Joe or Mike, or both?

Kev, if you take it as far as wanting to measure magnet strength for matching, be aware that purpose built gauss meters don't come cheap. A cheaper viable option is to use a "small parts" electronic scale. They can be used in reverse - by that I mean they will measure pull as a -ve value. 

I bought one and simply used dry transfer dotted lines on the underside of the clear cover to allow consistent magnet placement which is extremely important. I place the mag face down, top towards me and it pulls the measuring surface up to give the -ve reading. I glued the black Meccano (ferrous) plate to the weighing surface which is stainless steel (non-ferrous). Like any method, the results are only useful and comparable for magnets used on my scale.

An example of it's reading would be that AFX standard red/white mags usually read somewhere between about 15.00 and 23.00. I may be wrong but I'd think that a four digit number is more than adequate for matching purposes.

Best of luck sorting it all out. It's a very enjoyable learning curve.

Cheers,
Michael. :thumbsup:


----------



## slotking

btw
do not store ceramic magnets with neo mags
the neo mags will weaken the ceramic ones


----------



## krazikev

slotking said:


> you have to keep the flux moving north to south.
> 
> for example
> if you have a horseshoe magnet, they use a magnet keeper
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> the bar keeps the flux field moving from north to south
> 
> so if you do this
> (((((((|)))))))
> 
> you will still need something ferrous to connect the 2 far ends
> 
> something like
> 
> |(((((((((((((((|
> |___________|
> 
> and 1 for the opposite mag
> 
> Rare earth mags do not have the same problem


what kind of "bar" should I use? any piecs of metal? can I use the tjet round track connecters? I have tons of those along with tons of mags. and is it ok to store them on top of each other? like 3 rows of 20, 60 total. and last but not least is it safe to store the north ones with the south ones? and mix the colors? sorry for all the Qs, thanks


----------



## Grandcheapskate

Jisp said:


> I now realise that I'm guilty of storing my mags incorrectly..... ((((()))))
> 
> Soooo, who's right? Joe or Mike, or both?


I think we are both saying the same thing. Seems to me that storing the magnets on a metal plate does connect the magnets at both ends. Yes? No?

I am actually guily of only storing my old magnets this way. New magnets I buy (like Dash) have been stored in a plastic compartment case with the magnets arranged as I show above and also in multiple levels.

Thanks...Joe


----------



## slotking

> I think we are both saying the same thing. Seems to me that storing the magnets on a metal plate does connect the magnets at both ends. Yes? No?


kind of! LOL

I did not think about them actually sitting on a metal plate?
But if they sit on a metal plate I am not sure that makes a flux circle like the horseshoe magnet keeper. the horseshoe magnet is easy because the north and south end are next to each other.

you may be right that (((((())))) works??
I will contact the magnet manf guy I know.


----------



## dtomol

*HO Tjet magnets*

This is the helps. 

Nacho Magnets Strength Neodymium Motor Magnets

Stock Aurora red/green 11.5, 11.7, 10.2
Super II's 16.7, 16.8, 18.2, 17.3
Auto World Tjet Magnets 17.9 18.0
Dash 20.2, 19.5, 20.4, 20.3, 20.7, 20.6, 20.6, 18.5, 22.25
Nacho Poly Magnets 67.9, 69.7, 70.2, 68.5, 68.7, 71.2, 70.5
Nacho Dark Blue Neo's 191.4, 192.7, 189.5, 194.3
Nacho Light Blue Neo's 271.5, 266.6, 284.4
Nacho Dark Green Neo's 272.0, 266.3, 285.2
Nacho Lt. Green Neo's 275.9, 280.5, 286.5
Nacho Yellow Neo's 316.8, 318.9
Nacho Orange Neo's 325.5, 329.5
Nacho Red Neo's 381.8, 382.5
Working hand-in-hand with the armature, this is one of the biggest performance decisions you can make. If you just keep trying different magnets you will eventually find a set you are happy with, but making an informed decision will net much higher performance. Generally speaking, the stronger the magnet the better the acceleration - too strong and your car won't roll (coast) as far when the trigger is released. This is one of many places where your driving style can be 'synced' with the power of your magnets, armature choice and track design & layout. The most important thing about your cars magnets is that they are Matched. Matched magnets are a pair that have generally equal strength. If they aren't matched, even a Balanced Armature will be rendered ineffective because the stronger magnet will always pull the closest wind harder to that end of the chassis, creating vibration and potentially unstable operation.

There were many different Aurora magnets made for 'The Fabulous Pancake Motor'. The only way to determine the origin is by their colors, or lack of them. One thing we've learned is you can always be surprised - magnet colors that that are historically "supposed to be weak" can sometimes turn out to be stronger than you would guess! We know this through measuring with both our own home-built Analog tester, an FRHO Gauss tester & a BRP comparative tester. Lets take a look at some different magnets by strength - We'll rate their strengths from 1 to 5 (5 being strongest) since that's how our Analog meter rates them.
By the way, only tall (White/Red) & (White/Black) magna-traction & X-Traction Magnets rate a 5+. Before you get any wise ideas, cutting or sanding a set down will reduce their strength slightly. Also, a pair of MT or XT Magnets may be matched before you cut, but may not be matched when you are done. Keep this in mind if you decide to go that route, re-matching if necessary. Remember, actual gauss will vary from meter to meter, so our rating is a comparative rating based on our analog gauss tester. 
________________________________________	back | top


•	Johnny Lightning X-Traction (Playing Mantis)
•	North: White
•	South: Red
•	Rating: 6.0-6.1
We know these aren't Aurora, but they are also plentiful and so powerful that they have to be recognized. The following 'Factory' Magnets are listed from Strongest to Weakest, so we put the JL X-Tractions first. If you want strong magnets for your magna-traction, get a pair of these. We've have tested over 10 pair and they have consistent measurements as the strongest ceramic Magnets for the MT/XT you can get. They are basically matched out of the box. We haven't 'cut' a set down for T-jets yet to see if the strength is any better than their JL 500 little brothers, but will report our findings here when we do. 
________________________________________	back | top


•	Johnny Lightning T-jet 500 (Playing Mantis)
•	North: Light Blue
•	South: White
•	Rating: 4.7-4.8
If you want strong magnets for your T-jet, get a pair of these. We've tested many pairs and they have consistent measurements as the strongest non-polymer, non-neo magnets you can get. These too are basically matched out of the box and are becoming more common in most Fray racing classes. They have a slightly different shape than Aurora magnets and fit a little snug in an Aurora chassis. If you think you are going to re-paint a pair and sneak them into an event, a good tech inspector will spot them immediately - don't try it. However, if rules allow for them, use them!

Depending on the Rules, sanding or grinding the small rectangular 'end faces' will not only produce a nicer fit (resulting in less chassis 'twist'), but also bring the magnets just 'that much closer' to the armature.
•	Jet's post on Auto World vs Johnny Lightning Magnets

________________________________________	back | top


•	Super II "Fully Oriented" Magnets
•	North: Yellow, Black
•	South: Blue, Green
•	Rating: 4.5-4.7
Also known as "turbo" magnets, these are the strongest magnets Aurora ever produced. Available in the ill-fated A|FX Super II cars and on the aftermarket, these magnets are easily identifiable by both color and a little "dimple" cast into the center of each magnet. The "magic" of the dimpled magnet is the "full orientation", meaning that manufacturing tolerances were such that these magnets should have a consistent strength across the entire face.

Some or all Genuine Super II chassis's came with fully oriented pairings sans dimples! I don't currently own a Super II (it's been many years since I have) so I can't confirm or deny this, however it went uncontested in the usually spirited discussion list. It was also reported that there were 'carded' Black/Red pairings offered by Aurora that also displayed the 'dimple'. 
________________________________________	back | top


•	Xlerator (Later Clamshell Style)
•	North: White
•	South: Orange
•	Rating: 4-4.5
We've only ever had 2 pairs of these in our hands. They came in the Xlerator slotless racing cars that have the 'clamshell' tops and were also available (though not readily) in the Aurora aftermarket. They can also be identified by the dimple. There is speculation that these were simply Super II's with a different color combo. That's probably correct, but of the 2 sets I've had since building my magnet tester, they measured just a hair below Super II's in strength. 
________________________________________	back | top


•	Tuff Ones & XLerator (Early T-jet Style)
•	North: White
•	South: Green
•	Rating: 3.0-3.3
These were probably the strongest non-dimpled true T-jet magnets ever offered. We have a few 'untouched' 'Tuff Ones' and have tested the magnets, so we're am pretty sure about my findings here. Green & White could also be found in most early XLerator chassis's as well, with strengths in the same range as the Tuff Ones. It had been suggested previously in the HO DL that 'Aurora wasted nothing', and I believe it. As was probably the case with the White/Orange dimpled magnets, the White/Green XL magnets were possibly the same 'batch' as White/Green Tuff One magnets. 
________________________________________	back | top


•	AFX Non magna-traction
•	North: Light Blue, White or Green
•	South: Green or Orange
•	Rating: 3.0-4.0
This is where things get muddy. if you have a bunch of A|FX parts that got intermingled with your T-jet stuff over the years, then you can't be assured of any type of match without performing measurements. The strengths varied wildly during the A|FX years with colors that matched T-jet colors. Some were designed for 'Blue Arm'd' Specialty Chassis's, while others were for first, second or third generation A|FX cars - strengths vary wildly. 
________________________________________	back | top


•	Open Rivet Copper Thunderjet 500 (T-jet)
•	North: Green
•	South: Orange, White
•	Rating: 2.0-3.1
These are probably the most common magnets you'll find in the 'used' T-jet market, due to the remaining NOS chassis's available being (for the most part) outfitted with these. The strengths aren't bad, but they can vary. The Green & White combination has been reported to be a little stronger than the Green & Orange t-jet combo - supporting evidence can be found on the VHORS site, specifically the results pages. we did find 1 pair of the Green/White combo in our collection of magnets and they did score towards the upper end of our rating system at 3.0.

Be careful when choosing these by color alone due to these colors being available as A|FX too - Pairing a rating 2 magnet with a rating 3 magnet can actually yield lower performance than 2 magnets with a 2 rating. Did you catch that? 
________________________________________	back | top


•	Solid Rivet Copper Thunderjet 500 (T-jet)
•	North: Black
•	South: Black, Black with White Stripe
•	Rating: 1.5-2.2
Now someone may disagree with us, but this is what we've found. The earliest T-jets had multi-colored armatures, like the Christmas Tree Arm. Later early models had Copper wire / Grey tipped armatures. Christmas Tree Arms came from Aurora with Black / Black magnet combos and they are the Weakest of All Magnets.

The Grey tipped Arm magnets came with Black / Black as well, but the rear magnet had a white stripe on it. The pairs with the stripe were stronger than the pairs without - so - again, chance for mismatch... due to the front magnets always being unpainted black coming in 2 strengths! Without measuring, chance for mismatch is high. 
________________________________________	back | top

Thanks to Vincent Piazza, as he contributed much information during his extensive research and personal information gathering. Slugger, as he took the time to snap a photo of his collection of Pancake Magnets and provide it to us for this article. Much of the information about 'out of production' pairings was gathered from members of the HO DL. 
________________________________________	back | top


----------



## slotking

dtomol,

nice report

The whole concept is interesting.

for example, I found a 17ohm arm that screamed with the stock t-jet white/green mags. I thought it would be a good fray arm but it sucked with the super II to dash mags.

So I play with the various strength mags to find that sweet spot.
Most of the white/green mags I have gaussed are in the mid 500 range.
but I have found some that go all the way to 700+ gauss.

That is what worked well with that arm, so I used it in a nostalgia car.

bottom line, I found I have to test each arm/magnet combo to make the best car.


----------



## Bill Hall

slotking said:


> ******
> 
> ....bottom line, I found I have to test each arm/magnet combo to make the best car.


Truer words have never been spoken.


----------



## Grandcheapskate

That report is a direct copy from the Slot Monster site.


----------



## dtomol

*ho tjet magnets and armature questions*

The bottom half is a copy from slot monster's the top 1/4 I added from information I got on Hobby talk.


----------



## krazikev

thanks for all the great help guys


----------



## copperhead71

*Splitting hairs?*

Am I splitting hairs? When going thru my super 2 magnets in these cars,the two cars on the bottom row only have the dimple on one magnet on each car,is it best to just mix match them so that one set has both dimples?(if I do that then the paint jobs on the magnets will be very in uneven!)Also will it make any differance in a car with a 2.9 quad arm/and brush tubes if I leave the magnets as is?(one doted and one not)


----------

