# Pancake Armature question



## cwbam (Feb 8, 2010)

I got a working xlerator 1 quadralam chassis, arm was spinning ok in chassis.
I took it apart to ohm rage it I got (I did this a few times)

14.2
14.3
27.3

1 pole almost double the others.

Any ideas ? 
just random thing? 
a very unbalanced electrically armature? 
Why are they in demand on ebay?
FrankenJets? race series?
thank you


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## smallscalebill (Sep 19, 2010)

sounds like a broken wire. smalls


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## alpink (Aug 22, 2010)

that arm is fried. anytime one pole is very much higher than other two, it has exceeded it's life span.


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## rholmesr (Oct 8, 2010)

Yes, I'm afraid your arm has a broken wire. Sometimes this can be fixed if it's broken on the final turn of the winding - simply unwrap one turn and then solder it back onto the pole. However if the break is somewhere else in the winding it can be impossible to fix.

If you are able to fix the broken wire, your particular arm will probably ohm somewhere around 9.5 ohms each pole.

If you put a good one of these into a t-jet it can be a real screamer with a lot of torque. I have made a couple of them. So fast I had to glue some traction mags to the bottom of the chassis to make them driveable. They're fast (and maybe somewhat rare too or at least unusual) so that's why they have ebay demand most likely. In addition, the bodies that come with them are t-jet but different paint schemes that look cool.

In my local group I'm the only guy who has any of these 'frankenjets' so we don't ever race them. I just made them for fun to see how fast they would go.


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## TheRockinator (May 16, 2007)

on the other hand. If it was working well and you just ohmed it out of curiosity put it back in the car and use it. Who cares what a meter says if it's working? Sometimes it's best not to check on things that are working properly.

Later The I guess I could have said if it ain't broke don't fix it Rockinator


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## Bill Hall (Jan 6, 2007)

*Doomed*

The Xccelerator armature is a delicate affair as the comm plate has no retaining lugs around the outer edge. The plate is frequently loose or canted out of plane. Due to their high operating RPM they like to toss their winds and broken wires are the norm. Quality and performance are all over the place from my limited observation. 

I suspect that they command deeper coin for two separate reasons. They didnt make a whole lot of them compared to other models so they are desired by those who collect them for what they are.

Then the performance fables and subsequent frankencar attraction serve to raise the demand above what one would consider to be normal due to the competition between the two camps.

Like any design it is limited by it's make up. When combined with the rarity and additional cost of parts, a high winding, tall geared platform with limited potential for body lowering (due to the quirky gear rack) will never be much more than a novelty that we kick around in forum from time to time.

Having built a just few of them, I never could see much point unless one has nice big radius Super Oval where you could really turn them loose and truly enjoy their hairy potential. I had a nice example with a red T-jet Ford J on AFX turbine wheels. I never saw much of it as it always disappeared into the hole in the drywall at turn 1. :tongue:


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## rholmesr (Oct 8, 2010)

Bill - true dat about speed vs control. I have a buddy with 25 foot straights on his track and boy does that xlerator t-jet scream down the straights! 

And the design is super flimsy with the whole top being made from a bent piece of brass attached to the idler-gear clamp thing. You have to tweak on 'em to make them go together right and if you wreck then the whole thing can come apart. I have seen a 'clamshell' one that a buddy had and that looked a lot more robust but I don't have any of those.

And like you said the com plate is just floating there and cannot be adjusted or really secured to anything solid.

I made a 'hop up' gear for one of mine by soldering a couple of 14T pinions together with a space between them rather than the standard xlerator 15T/9T combo. That changed the car from being super-fast to being insanely-fast. Seems like I can run it for about 5 minutes between oilings. Between the brass gears spinning on a metal spindle and the top arm shaft spinning like a tornado in that super loose plastic bushing it just won't stay oiled.

But all that said, it was definitely fun to engineer a solution to the franken-car concept from a pile of parts that I found on the cheap (i got a box of old xlr parts from a co worker for maybe 20 bucks).


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## alpink (Aug 22, 2010)

*franken ....*










monster 5 lam train armature. had to change the idler and flip the clustergear. added bushings top and bottom of arm because of smaller arm shaft diameter. 
runs well and has good top end, but takes too long to get there. runs hot quickly. fun experiment though.










http://s293.beta.photobucket.com/user/alpink/library/monster armature and drag strip

:drunk:


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## rholmesr (Oct 8, 2010)

Al - I remember that thread. I bet that thing would do 40 mph if you had a long enough straight. cool!


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## smallscalebill (Sep 19, 2010)

is the aurora clam shell top a better option for keeping everything in place? smalls


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## Bill Hall (Jan 6, 2007)

" You have to tweak on 'em to make them go together right and if you wreck then the whole thing can come apart. "

Yeah totally!....like the "Smash up Derby" set from Kenner when I was a kid. 

Your comments jogged my memory. Back when I was 'sperimenting with them, I also noted that the T-jet comm brush lever spring arrangement was ill equipped to cope with the end float. Keep in mind that the factory modified the brush support for the Quad in the Superll, and changed it for the Xcellerator, then carried that particular design over to the highly reliable and successful Magnas.

The T-jet comm springs set up is actually a down grade and arguablly problematic.


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## Dyno (Jan 26, 2009)

Bill Hall said:


> "
> 
> Your comments jogged my memory. Back when I was 'sperimenting with them, I also noted that the T-jet comm brush lever spring arrangement was ill equipped to cope with the end float. Keep in mind that the factory modified the brush support for the Quad in the Superll, and changed it for the Xcellerator, then carried that particular design over to the highly reliable and successful Magnas.
> 
> The T-jet comm springs set up is actually a down grade and arguablly problematic.


I believe this is 100% correct. I built one a few years back. It had great torque and NO top end . The one my friend built was much faster. I shelved it for a while and tinkered with it a few weeks ago. I tracked it lack of performance to weak brush springs. No matter how I adjusted them they would not hold tension. Since I have nothing better to do today, maybe I will put it in a Tuffones chassis. Those have much stronger tension.


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## SouthLyonBen (Mar 14, 2012)

I got most of the parts to build one of these except my xcellerator gear clamp holder thingies are missing the bushings, I never really understood the point of that set up in the Xlr cars. Do you use Magnatraction size magnets in the TJ or make little spacers like the slotless cars had? I still ponder time to time about trying the train arm experiment again, I have a whole 'nother unmolested pancake train/gearbox hmmmm


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## alpink (Aug 22, 2010)

I can send ya some bushings. PM me your mailing address.


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## Dyno (Jan 26, 2009)

SouthLyonBen said:


> I got most of the parts to build one of these except my xcellerator gear clamp holder thingies are missing the bushings, I never really understood the point of that set up in the Xlr cars. Do you use Magnatraction size magnets in the TJ or make little spacers like the slotless cars had? I still ponder time to time about trying the train arm experiment again, I have a whole 'nother unmolested pancake train/gearbox hmmmm


I suppose you can use t-jet mags with spacers but Magnatraction magnets just drop right in.


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## Bill Hall (Jan 6, 2007)

Hard to find, but those early "T-jet sized" Xcellerator magnets work really good in geeked up T-jets! They'd be the T-jet colored mags that are about Super ll strength that you find in tangled piles. 

We quickly learned that Magnas became snarling beasts when you dropped a 6 ohm arm in that chubbier magnetic field.

The Magnatraction magnets were my preferred choice for the T-jet/ Xcellerator conversion. A DROP IN FIT with a larger well centered magnetic field is the go-to method. The stickier AW Four gear magnets are a good choice for some added grunt.

A piece of two sided tape on the front of the gear combobulater will stick it right to the forward magnet and keep it from...er....uh....re-combobulating!


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## partspig (Mar 12, 2003)

You can, for all practical purposes, eliminate the "float" problem by replacing the T-jet electricals with those parts from a later "toasted" maggie chassis or by using Super II brush cups. Either way will work good, I have done both. Although, replacing the t-jet electricals with AFX ones, is somewhat more difficult than the brush cups, it works. pig


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## SouthLyonBen (Mar 14, 2012)

Anyone dabble in European trains? Wondered if the Hornby armature was even remotely usable. Here's a 5 pole version for your slow street runners! 
http://www.newmodellersshop.co.uk/hornby_spares/x9024_hornby_spares_5_pole_armature_a3_a4.htm

Can't find squat on specs like shaft dia


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## Dyno (Jan 26, 2009)

SouthLyonBen said:


> Anyone dabble in European trains? Wondered if the Hornby armature was even remotely usable. Here's a 5 pole version for your slow street runners!
> http://www.newmodellersshop.co.uk/hornby_spares/x9024_hornby_spares_5_pole_armature_a3_a4.htm
> 
> Can't find squat on specs like shaft dia


From what I have just found online, that armature is about 21 mm in diameter. That would make it .8268 inches, slightly too big. Also it looks like it has about 8 laminations making it too tall also.


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## SouthLyonBen (Mar 14, 2012)

Dyno said:


> From what I have just found online, that armature is about 21 mm in diameter. That would make it .8268 inches, slightly too big. Also it looks like it has about 8 laminations making it too tall also.


Bummer, since the high ohm 5 poles won't work I'm not even going to bother working on my Buick Roadmaster resins......


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## SouthLyonBen (Mar 14, 2012)

you guys build your frankencars on a T-jet or anyone modded the Xcel chassis, I was messing with one earlier and seems like a normal axle fits and I just need a front end and pin, pros? Cons?


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## alpink (Aug 22, 2010)

Ben there have been both. most folks build em on t-jet chassis. but there might be advantage to putting a front axle and guide pin on an XL chassis. if you use t-jet chassis, tall magnets fit pretty nicely and put the sweet spot of the magnetic field right where you want it, like Bill has said.


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## SouthLyonBen (Mar 14, 2012)

Yeah I was just thinking that maybe things my or man not work better in their natural environment (xl chassis) all I've seen in my memory is swapped over to a thunderjet.


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## Dyno (Jan 26, 2009)

SouthLyonBen said:


> Yeah I was just thinking that maybe things my or man not work better in their natural environment (xl chassis) all I've seen in my memory is swapped over to a thunderjet.


I was thinking about using the xl chassis also by making a front end because it has those strong brush holders. Just break off the resistor or whatever it is and solder the connection. The drawback is that the magnet pockets have those nubs that need to be ground out to fit taller magnets. Or you can just use tjet size polymer magnets.


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## alpink (Aug 22, 2010)

polys might not work well with that arm. or, they might. be prepared to disappoint.


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## slotcarman12078 (Oct 3, 2008)

That resistor thing is a diode that only lets power go through in one direction. It's easy enough to cut it off and solder a bridge there. Making the front axle mount is going to be the tough part.


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## tjetsgrig (Nov 1, 2009)

TheRockinator said:


> on the other hand. If it was working well and you just ohmed it out of curiosity put it back in the car and use it. Who cares what a meter says if it's working? Sometimes it's best not to check on things that are working properly.
> 
> Later The I guess I could have said if it ain't broke don't fix it Rockinator


 Heat is a factor in this instance. With readings that outta whack, it will overheat, then yer melting the chassis brush holes!

JS


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