# T-jet questions / comments



## valongi (Dec 23, 2007)

I didn't want to hijack the other T-jet thread, so I'm starting this one. It's about my observations from picking up a couple T-jets over the last couple of weeks.

I'd bought a dash body, and mounted it to a Tuff One chassis. I also bought an AW T-jet Ultra G.

a) the Tuff One chassis runs like crap. Very squirrily, the rear wheels spin everywhere on a track- straightaway and turns- and no shocker, has terrible traction around any turn. I'm assuming it's a TO, based on what the vendor told me at the show. The top of the chassis has a Playing Mantis copywrite.

b) The ready-to-run AW car was better, has a neo magnet so it's a bit more sticky. The wheels don't spin like the TO chassis.

Now I completely understand the allure of the T-jets, and want to add them to my growing collection. My nephew and I love to race the SG+ and SRT cars, but the T-jets could add the dimension of just cruising around the track, mastering the art of controlling a car. Tom's dash bodies are spectacular, and the few AW bodies that I've looked at are nice as well. So I'm not here to start an "I hate T-jets" discussion, I'm looking for some constructive feedback 

I've noticed that there are a handful of factors in a car's success:

a) Track layout / quality of connections between sections. You're not going to be able to push a T-jet at full tilt around technical layouts. Inconsistent grooving (pin hitting edges of track sections), and of course shoes keeping contact with the rails.

b) Skill. I'm a newbie to T-jets, and it's an acquired taste with patience required. Whole 'nother world compared to the SG+ / SRT chassis. 

c) Chassis components / tuning / quality.

d) Power / controller quality.


I'm still working on b, c and d.

Questions:

1) I'd love to be able to pick up some dash bodies and build my own car, so should I look to pick up the Ultra G chassis separate?

2) Performance- what's a reasonable expectation? Am I looking at a car that's going to need special handling around the turns? Should I expect the AW Ultra G to be the high-water mark for T-jets?

3) How can I prep my track to handle a T-jet? A good Formula 409 cleaning?


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## twolff (May 11, 2007)

There’s nothing unusual in your description of the two cars. The Ultra-G is easily the best running out of the box in the history of these repros (Johnny Lighting and AutoWorld). Neither of the chassis is actually a T-Jet. Each release of the chassis has suffered problems of one sort or another. Most have a sloppy fit between the chassis and axle and wheels and tires that are out of round. The Quality of the XTraction chassis (Magnatraction repro) had been no better, but had different problems. The lighted XTractions that I’ve tried have been unusable for just running with the kids in the basement (all I do with these BTW).

Many of the Johnny Lightning/AutoWorld bodies are nicely done. Others can make you wonder why they even bothered. The chassis can serve as a source of spar parts for authentic T-Jets or you can build useable cars with the parts from several of them if you buy enough of them from different production runs. There are a few here that insist on judging these cars based on the intent of the guy that created them rather than the quality of the final product and are hell-bent on polishing these turds. Some of them will get offended and call me names for posting my experience with these cars.

You should grab a few org. T-Jets from someone here on the board or off eBay. All the NOS Aurora chassis I’ve purchased needed only a few drops of oil and softer tires to be completely useable. They are generally slower than the Johnny Lighting “Tuff-Ones” because they use a lower gear ratio and usually a tamer motor. I’ve had great luck “bottom feeding” old T-Jets on eBay. Most need only a good cleaning and a part or two. Plan on replacing the tires on anything you buy. You will need to be careful and ask eBay sellers questions or you will probably be disappointed. On the other hand, I don’t know of anyone on this board that would sell you junk or something other than what was requested or advertised. For example, you won’t find someone here selling NOS Aurora T-Jets and sending Johnny Lighting/AutoWorld or Model Motoring stuff instead. Speaking of Model Motoring. That’s another reproduction chassis you need to watch for. The chassis is just slightly smaller, but looks very much like an Aurora T-Jet. The overall fit of the parts is better than the Johnny Lightings, but many of the parts are not interchangeable with the Aurora T-Jet.

Weird Jacks silicone tires have worked very well for me on my plastic Tomy track. Better than anything else I’ve tried. Stock fronts work ok as long as they are round.

A 90 ohm or higher controller will make the T-Jet style cars loads more drivable. Stock set controllers feel like an on/off switch by comparison.

I consider the Ultra-G a magnet car when compared with a T-Jet or ThunderJet 500. It handles a lot like a Magnatraction car. Nothing wrong with that if that is what you’re after. It may be what you wind up enjoying the most and that is what it’s really all about.

There’s a lot more, but I’m tired of typing. Have a read of the various threads here in the forum. There’s a lot here.


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## TK Solver (Mar 18, 2004)

They're definitely not toys to give to kids on Christmas morning.

Limiting the pick-up shoe travel is important in preventing deslots. I don't understand why they make the stock pick-ups the way they do, knowing that by reducing the travel by even 25% would help a lot.

For many this is blasphemy, but you can glue a small disk magnet to the bottom of the TO chassis and it will perform similar to an Ultra G. Various disk magnet suppliers are out there and you can get a tube of up to 100 shipped for less than $20. I think one magnet supplier is a HobbyTalk sponsor.

Weird Jack's or Bud's Lo-profile TO silicone tires will both help a lot.

Without adding magnets, a 90+ Ohm controller is a must for standard plastic track and stock transformer power.

I have also found that replacing the motor brushes with Wizzard brushes from Bud's always improves performance.

Why go to all this trouble? For me, it's because so many of the bodies that fit on these chassis look nice. I'm hopeful that Dash's "TurboJet" chassis becomes an economical and reliable alternative. We'll see...


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## Peacefield (Jan 22, 2008)

I don't race competitively and I don't have nearly the technical understanding of most on this board. That said, I've nearly completed a scenic layout with 95 running feet of track; two long (14') straights and lots of curves of varying radii. I love my magnet cars, but I love my TJ's, too. Here are a few thoughts from my perspective.

As TK says, a 90 ohm controller is a must. $50 for a pair, but the best money I ever laid down on this hobby.

Rarely do JL and AW TJ's work great out of the box. Tires are often irregular and sometimes need to be trimmed or sanded so that they are truley (or at least approximately) round. Also, it pays to break in a new car. When you put a new car on the track for the first time, (after oiling, of course) rev it at a slower speed for a minute or two, than increase gradually to full speed. I think this allows the brushes and all to fit together better for the life of the car.

There's a lot that can be done to help with deslotting (the most frustrating thing for me in all of TJ racing). The simplest way, though, is to just take a small lead weight (I use the kind that you'd squeeze onto a fishing line) and hot glue it to the chassis right over the pin. It allows the cars to behave SO much better. And unlike the original Aurora's, JL's and AW's have power to burn so there's no real issue with that tiny weight slowing the car down at all.

Lastly, think about your driving style. As I tell my (now 18 year old) sons, drive a TJ like you would drive a real car on snow. Coast into the curves and power out. Don't gun it down the straight so hard that your wheels start spinning; accelerate smoothly. TJ's really do need to be driven like a real car.

As has been said, the original Aurora's (I'm fortunate to still have the two that came with my 1965 set) run wonderfully. They're slower; so much so that banked curves can become an obstacle, but the are smooth through their entire power band and their drifiting is very manageable. Modern TJ's will never run as nicely, but a 90 ohm controller, a little weight in the nose, a little tuning of the wheels and tires, and a more gentle style can make for a lot of fun racing. 

Enjoy.


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## Bill Hall (Jan 6, 2007)

*Fundamentals work good*

All well said guys. 

My bottom line is that you need to aquire a few examples of whatever chassis design suits you. From a wider parts base you can learn whats good er bad by swapping things around. In time you'll learn what combinations work or what interchanges between individual designs. IMHO the big pinion setup on todays pancakes is part of the problem. The tuffy tire profile is smaller and the tires fry. When they do get hooked up you need some track length to use the amount of leg they have. Larger profiles only exascerbate the problem. For me the solution was conversion to a nine tooth set up and better driveability on a shorter course. The ability to change a t-jet pinion was one of it's great assets. Not unlike todays mag cars where ratio changes are easily executed albiet a little more involved on a t-jet. 

Ultimately tuning ability is aquired through experimentation. The failures teach as much as sucesses and both have a story to tell. It's up to the individual to solve the riddle of why one set up or design performs in a certain manner. The variables come into play quickly when you start playing with different setups and in the end game when you get into the realm of some of our sage tuners here...thousandths matter! In other words the farther you push the envelope the tighter the margin for error becomes. 

Learn to tune a stock set up to it's maximum potential before you start throwing cash at high performance parts. TW makes a valid point regarding wheels/tires/axles. Making the rubber meet the road properly is perhaps the single most important upgrade and more often than not is the answer to the bulk of most out of the box handling problems. While I've been doing this for years...I call it the "Swamper Gene" rule cuz it is his mantra and a darn good one! Your eyes, ears and nose are your best tools...the trick is learning to interpret what the heck your senses are saying. At some point you'll know what's going on by a focused look, a careful listen, or a whiff of fire, LOL!
When ever I get well off course on some tuning tangent a return to basics always seems to get me home. 

This is all of course secondary to investigating any excessive frictions in the drive train that should be checked out prior to running the car. It is job #1. Excessive frictions can make your car handle weird or twitchy no matter what controller you use. 

After you can clean up an out of the box stocker with confidence, you can move on to more complex things like shoe tuning and the relationship between tire setups and what each does to the other. Each modification to a particular area of the chassis effects another area. Some effects are direct and some are proportional. Tire sizing affects shoe tuning and vice versa. Shoe tuning affects handling and current path to the motor. Magnet strength and comm. spring pressure affects motor performance and handling. The relationship between armature performance, final drive, and tire profiles is another interestingly tangled relationship. 

There is enough great information on tuning to fill many volumes so let your fingers do the walking. Acquire enough chassis so that you can shuffle good parts in and bad parts out. I break them into three piles based on how they run after breakin and inspection...I use the good, the bad, and the ugly system. Take the good and inspect the wheels/axles and upgrade the tires so you have a bench mark. Use the bad and the ugly to cut your "tuning teeth" on. Shuffle the parts around systematically in an effort to bring them up to your bench mark chassis. After all ya cant make them any worse. Once I get the initial break-in and sort out done, I set the rockets aside for future hotrodding projects. The middle of the road is used for runners or guest cars. The junk is tossed out and the usable is raked back into the parts bin.

With a little effort, odds are if you have half a dozen or so chassis you should be able to find enough good stuff to build 2 er 3 smooth, responsive chassis and establish a learning curve. 

I've got an assortment of cars from the light benders, tourqey twitchy t-jet hotrods to their stock t-jet singer sewing machine counter parts, vibrator cars, worm drives and points inbetween. I love them all. They all have a place in the greater scheme of my slot addiction. 

For the most part I find it unrealistic to directly compare one design against another beyond the fact that they are different and EVERY design has some good points or bad points based on track designs or conditions. They are all similar in that I derive great pleasure from them whether I'm putting vibrators with the grandyuns or cutting drywall with the big kids!


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## valongi (Dec 23, 2007)

Excellent feedback, thanks guys. I wasn't looking for specific answers, but the direction in which to look and go that's been expertly stated here.

T-jets appear to be loaded with nuances to experiment with and learn, where the newer cars are certainly more ready to run with less tuning. Both have a spot in everyone's slotting hobby 

Certainly looking forward to the next LI show, so I could pick the brains of the experts!


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## T-Jet Racer (Nov 16, 2006)

I like the J/L aw t-jets. they run quite fast and if you throw a magnet on them they are a lot of fun. The original Aurora cras are great, run smooth and don't need a load of work out of the box. I have a few Johnny Linghtning playing mantis chassis that I added a neo magnet to, restricted the pick up shoes, and put low profile tires on all around and they run like mad! I have one with a model motoring vette body that is truely wild, faster than a lot of my afx magnatrction cars. The repro chassis do leave a lot to be desired but if you "play" with them they will suprise you Good Luck


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## AfxToo (Aug 29, 2003)

Part of the allure of the JL/AW TJets is to turn the squirrelly little beasts into well behaved runners. The biggest problem going in is the fact that they are overgeared for all but the longest and gentlest track layouts. The Aurora TuffOnes were much the same, except they came with too low of a resistance arm with too little motor magnet and had a tendency to run hot. If you have the right tools you can put in stock TJet gearing in a JL/AW and improve their attitude tremendously. As others have said, clamping them down with a 90 ohm controller helps too, but at the upper end they will still want to break loose.

There are a couple of things to try to slow them down. If you have some old Aurora TJets you can swap the magnets from the JL/AW with the Aurora ones. You can also reduce the brush tension a little to loosen the car up and give it more roll. Once you get a little more roll in the car you can let off the throttle going into a corner and let it roll a little before getting back on the throttle. Other things that improve the roll, beside lighter brush tension, are switching to a flatter, smoother brush like JBs ThunderBrushes, breaking in the gears, and using rounder/truer tires. A weighted front end, or weights as others have mentioned, also make the car roll better. With any TJet, the less friction in the drivetrain the better off you will be.


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## dlw (Aug 17, 1999)

*Quick Tune-up For Thunderjets*

Valongi, the AW/JL thunderjets are nice cars, but (as you've been told) they do need tweaking and tuning before you run them. Here's the quick rundown of what to do for them:

1 - Check the pickup shoes. Right out of the box, any AW/JL car (Thunderjet or Xtraction) usually has the pickup shoes at a bad angle. This is caused by the method they are installed at the factory. The pickups should be parallel with the car when it's on the track. gentle bending with needle-nose pliers or a screwdriver will do.

2 - Check for untrue rims and crooked axles. Remove the tires and closely look ay the rims as you spin them. You'll spot any wobbles. Remove and replace.

3 - Check the tires for little tree 'nubs', which come when they're plucked off the 'tree'. Some low-speed burnouts on fine sandpaper will fix that.

4 - Disassemble the chassis and add a small drop of oil to anywhere you see metal going through plastic. And put a drop under the brass armature gear, and wok it into the shaft.

5 - Reassemble the chassis and do a 10-15 minutes break-in with a 9V battery. reverse the battery and run for a few more minutes.

Your car should run better now. Silicone slip-on rear tires will help a lot.


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## roadrner (Jul 21, 1999)

Lot of great tips and advice here. Utmost remember to have fun. Once you start tweaking and building (or rebuilding) these things, It will all come together. Heck, you may even come up with some new idea or way to get an extra turn from the pancake. Enjoy and have fun with all the chassis out there you decide to play with! :thumbsup::thumbsup: rr


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## Grandcheapskate (Jan 5, 2006)

The fun of the T-Jet and AFX is maybe it's overcomplicated design. With the inline motors, there's not a lot to fiddle with. With the pancake motor and all those meshing gears, the possibilities for tuning are endless. And that's what makes it fun.

If you want something that runs well out of the box, go inline motor. If you get joy out of taking a poorly running car and bringing it to life, then pancake cars are for you. I remember buying a used AFX about a year ago. It wouldn't conduct electricity, let alone move. I worked on that thing for hours and now it runs as smooth as can be. There's a sense of accomplishment you feel after something like that.

Joe


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## SwamperGene (Dec 1, 2003)

Hey valongi, it's a little ride but we race this kind of stuff all the time, you're always welcome to drop by.


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## win43 (Aug 28, 2006)

Hi, :wave: my name is Jerry and i'm a Tjet-a-holic. I love the Tjets. :woohoo: Sure it's a pain sometimes tweaking this, doing that, and new tires here. BUT it is all worth it. :thumbsup: None of those "out of the box" super racers for me. I like the feeling of accomplishment when one of those little suckers I just got done tweaking turns out to be a screamer. :woohoo: I also still use Aurora lock and joiner track. :thumbsup::thumbsup:


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## RMMseven (Oct 22, 2004)

I run my T-Jets, both AW & original Aurora, basically all stock except for installing slip-on tires. Of course some of the wheels and tires are out of round and need to be repaired or replaced.
These cars require a significant amount of break-in running, 10 to 15 minutes, to run really smooth. I hook up a new or NOS chassis to a power supply and just let it run, I sugest a 9volt power supply from a calculator.
The voltage these cars are raced at is the most improtant factor to give good controll, at 22 volts with a 90 ohm controller helps but at the lower power of 14 volts you'd start having a lot of fun and has caused some people to ignore their magnet cars.
The funny thing is I started using my T-Jets a lot more because I didn't want to spend the time tweaking cars, the 440-X2 & Super G+ cars seem to need too tuning to run together.


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## TJETDRAGRACER (Jan 25, 2008)

Hay want a nice running t-jet that's runs strong and smooth 
1. Get a new or good used JL or AW t-jet chassis
2. Get a NOS or good used Aurora t-jet
3. Will need 2 new 14 tooth gears and a rear set of tuffone size silicone tires
4. Strip the JL or AW chassis of the magnets / arm / brushes / pick-shoes
axels / rear crown gear.
5. Strip the Aurora chassis of the same.
6. Sand down the JL / AW magnets to fit the Aurora chassis.
7. Use your 2 new 14 tooth gears to put the JL/AW arm on the Aurora top-plate
the other 14t gear to replace the 9t rear top plate gear that runs the crown gear.
8. Put the JL/AW rear axel and crown gear on the Aurora chassis.
NOTE: The hardest part to all this is replacing the 9 tooth gear to the 14 tooth 
on the bottom of the gear plate.
I have done over 20 like this. 
If you want I will do it for you for free / just will have to send me the one 
chassis (1) JL or AW / I have a spare bare Aurora chassis and top plate so 
you will not need to send that
Anything to help out a t-jet racer. 
Tom / Swartz Creek MI.


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## valongi (Dec 23, 2007)

Thanks, Tom. I'll have to give your suggestion a shot one day soon. Lots of feedback and advice here that validated my feelings that once done right, the T-jets are a blast to run with. I just need to dedicate some time in getting around to working on the chassis. Time and money, the rarest of commodities


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