# T-jet style Armatures



## dtomol (Mar 30, 2005)

In everyone opinion which armature configuration makes more power. Two lamination, three lamination or four lamination? The lamination on the quadrlam are thinner I think, but does the weight off set the added material
and slow the armatures acceleration?


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## 66Galaxie500 (Jun 18, 2004)

Also, which one makes the most torque? It would be useful for heavier bodies and die cast conversions.


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## cwbam (Feb 8, 2010)

some info on arms
http://slotmonsters.com/slot-car-afx-magna-traction-pancake-motor-armatures.ashx

I like green tip green wire (from AFX chassis nonmag) and AW magnets


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## rholmesr (Oct 8, 2010)

I'm not an armature winder but I do know about electric motor theory.

The amount of torque is proportional to the number of turns and inversely proportional to the resistance in the wire (in other words, lower ohms = more torque). You can see that this is a trade-off because as you add more turns, the ohms will increase.

The number of lams is probably a small contributor to the overall torque of the arm. Increasing the number of lams will increase the efficiency of the arm because that limits the eddy current losses along the length of the stack (each lamination break is a stopping point for this flow of current that is detrimental to the performance and only works to increase heat). So in that regard, more lams in same amount of stack length is better. Now can you measure a difference? Not sure.

If you stack on more lams and that results in a LONGER stack of lams, that will increase the amount of wire per turn, meaning your X-ohm winding has fewer turns, and this will cause the torque to decrease due to physics.

Of course this all assumes that the actual lamination steel is not completely saturated with magnetic flux (consult the B-H curve for the material selected!  ) Once the steel is saturated, it can do no more and only runs hotter but will not supply you with more torque. 

cwbam is right in that the mean grean AFX arm is a good one if you want speed and torque in a relatively inexpensive armature. Slotmonsters has a lot of good info on all the different arm types that Aurora made.


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## TeamMadMarsupial (Dec 23, 2012)

Not an expert by any means, but I have run Quadralam arms off and on in a few of my cars over the years. Have tried racing them inT-Jets, AFX Non-Mags and Magna Traction chassis. The two most apparent characteristics I have noticed regarding the Quadralams are that they seem to "spool up" a little slower than my Mean Green and aftermarket rewinds and on our long straights, they have a flywheel effect and carry a ton of momentem into the turns. We have several straights over 20' in length and a front straight right around 30', so the cars are running pretty fast towards the end of the straights. I must adjust my driving considerably to run a Quad. I have come to like them most in my AFX Non-Mag car as I also run these chassis with the SuperII weight kits along with some additional added weight. The added weight and momemtum from the arm pulls or pushes the car into the turn without applying power and allows, for me anyway, a smoother roll through the turn. An added benefit off the turn is the Quads slower spool up, making the accelleration off the corner a little smoother. Very un-scientific explanation, but just what I have experienced.


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## alpink (Aug 22, 2010)

when the Super II's came out, I was able to buy one via mail order directly from Aurora.
racing it on standard power supplies that came with track was a dissapointment.
I was able to send it back for a full refund and keep the bonus Quadralam arm too.
later, I learned that it was intened to run on commercial tracks with different (more powerful?) power supply.
having researched it in recent years it was a similar chassis what Porcceilli(sp) was whooping the TYCO guys with at the big money races.
Aurora hired Tony to help them develop a similar chassis that could be mass produced.
anyway, Tony wasn't happy with the compromises that had to made in order to machine make and assemble the chassis.
so, back to the Super II, .... it was intended for serious racers on commercial tracks and not home tracks.

my opinion, and not to diminish true scientific findings, it seems to me that additional laminations (given the same OHM of wire/winds) allows for a more magnetic fields.
a friend, Jim Sgrignioli (T-jet Jim) has experimented with 5 and 6 lam arms, maybe even 7.
his findings were that the increased power (torque?) caused other parts to fail more often.
along with the extreme cutomizations to gear plate, chassis, soldering gears to shafts, ...etc ... I think he came to the conclusion that a quad was the best for most purposes with the least amount of failure and hassle..
I am hoping that Jim weighs in on this issue with his actual findings and explanation.
I could, very possibly, have it all wrong.
LOL
your mileage may vary!


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## slotking (May 27, 2008)

just to add, wire size makes a difference as well.
mos of the custom arms I use have a lower gauge arm (thicker wire) than the stock arm.

Not sure about the quad, but I would think it may as well

some of the locals used to wind there own arms that provide some great light and smoke shows at some of our races


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## Rich Dumas (Sep 3, 2008)

Some day I will have to find a book on DC motor design. The armatures have laminations to reduce hysteresis losses. If you keep the total length of the stacks the same you could vary the thickness of the laminations and so change the number of them without altering their total mass. I expect that beyond a certain point there would be no use in having more laminations. For kicks I had some custom winds done on Johnny Lightning 3 lamination blanks. Compared to Aurora 2 lamination blanks there was not much of a difference, but to be honest I did not do any systematic testing. Dash 2 lamination arms are lighter than Aurora 2 lamination armatures, possibly the laminations are the same thickness as the ones used in the Dash 3 lamination arms.
Quadralam armatures use a double wind and those would have different characteristics than armatures with a regular single wind that have the same ohm value.


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## slotking (May 27, 2008)

Kipp used to do custom winds, he had 2lam & 3lam motors he sold.

His 3lam motors worked oh so well in my poly mag magnatractions

I miss his arms


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## TeamMadMarsupial (Dec 23, 2012)

I am still racing about a half dozen KIPP rewinds. They run as good today as they did when I first bought them and can keep up to most of my new rewinds!


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## dtomol (Mar 30, 2005)

*Tjet style armatures*

The spooling up may explain why my thunder jet with brush tubes super II magnets & Quadrlam armature seems slow off the line. I was racing a friend of mine 20 ft straight after 15 feet i was behind say 3 car lengths then the next couple of feet caught & passed him. It has custom made rear tires the aj silicone that have been turned into silfoams. It does not have the super II rear gear just a 15 tooth rear gear.


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## Bill Hall (Jan 6, 2007)

*Ball and chain*

The slow off the line has more to do with a reduction of sixth crown teeth than the pedigree of the armature. Thats almost a 1/3 increase in gearing. Thats gobs in gear speak. 

The beauty of the Quad is broad responsive power curve. Saddling it with a 15 tooth will certainly affect the location of the powerband's wake and fade points.


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## TeamMadMarsupial (Dec 23, 2012)

I run strictly afx/mag crowns on my T-jets and SuperII 19t on my AFX Non Mags. So I'm talking a switch in arm from a Mean Green to my Quads, results in a lag off the corners with the Quad to the MG when not changing the crown and a ton more coast at the ends of the straights. Must also be noted that we run 24 volts, all the amps in the world and no brakes on the controllers.


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