5 replies to this topic

[mcrusty1]

I have a '60's T-Jet and I'm wondering if it works. Is there a way to check with a battery or something? I tried a 9v but nothing, the car worked great last time we used it, but I don't have the track.

 

Thank you.

[John Miller]

Is it a vibrator T-Jet?

 

If not, those run on 18 volts, but a 9 volt battery should work just fine. Any DC source will test those just fine. Pull off the armature plate and make sure that the comm and brushes are clean and making good contact.

[Joe Mig]

I agree with John.

[Joe Mig]

Please post a picture of this car top and bottom.

[Hworth08]

I can't remember exactly how but it's easy to make a T-Jet dyno,
 
Put a silicone tire and wheel where the pinion was on something like a Tyco Pro motor. Then hook a multimeter to the motor leads. Power up the T-Jet and hold the rear tire to the silicone tire on the test motor. Read the voltage on the multimeter... the more voltage, the faster the T-Jet rear tire is turning,
 
Complete instructions are somewhere on the net. Maybe the NSA had an index?

[A. J. Hoyt]

Russell,

 

I had this same quandary racing with the HO groups here in Denver - no track to test on. The T-jets are the toughest. Some kind of a consistent wheel dyno is essential (in my opinion) as it tells you that everything is OK or if something needs attention. I kept records of all my cars (engraved numbers in the chassis and gear plates). With a dyno, the only thing that matters is the reading of one like car against another (relative values). It permits you to find that elusive combination of parts that makes good top end speed, especially if you are turning a rolling drum (most consistent way to get the axle loading right). You also need to standardize with one non-adjustable power supply.

 

I have found that 12 to 13 volts is a good place to test. My results were ALWAYS consistent in that the fastest cars on the dyno were always the cars with the fastest straight line speed potential.

 

That merely helps to limit the number of cars to work with at the track  because there are other equally important variables. Once the few cars with the best potential are isolated, put your best handling bodies on those and focus in on getting the pick-ups adjusted at the track. Look for a nice pattern of contact with the rail covering as much surface area from front to rear on the pick-up contact surface. I use a very sharp point marker and draw six or seven lines across the pick-up - this will reveal the wear pattern very quickly. Develop a means to adjust the pick-up angle so that the contact is uniform from front to rear (not only and the front and not only at the rear).

 

If it is allowed, limit the down travel of the pick-ups so that it lifts the inside pick-up off the rail if the car starts to roll. (If the car is rolling, it will cut the power and act as a "governor", perhaps preventing a de-slot but it "feels" like the car is handling better because it is automatic.) My rule of thumb for a starting point is to look at the bottom of the car and have the pickups be tangent to the bottom of the front tires. The rail always sits above the track surface so that is .008 to .013 of travel to ensure there is good contact.

 

Others may be able to chime in their tips but these are essentials if you do not have your own track to test on (like me). I like racing the T-jets. Today's ultra smooth tracks allow them to really "race" each other. The cars don't have to go fast to have a good race!

 

(Oh, yeah, and) Keep it in the slot,

 

AJ