Bachmann's Thomas The Train Decoder Install

Discussion in 'DCC & Electronics' started by railwaybob, Jul 3, 2005.

  1. railwaybob

    railwaybob Member

    My kids have long grown up but I couldn't resist it yesterday. I bought Bachmann's Thomas the Train. Now I want to install a decoder in it. Does anyone have any tips/ instructions on how to do a decoder install?

    Also, Thomas is stalling on the turnouts (Peco insulfrogs) as the middle wheel goes over the frog. Any tips as to the solution.
  2. MasonJar

    MasonJar It's not rocket surgery

    Hi Bob,

    Sounds like fun! I think Peter P at HOTrak has a decoder equipped Thomas.

    Good luck. Looking forward to seeing the little engine in action... ;)

  3. railwaybob

    railwaybob Member

    Well, we finally started working on Thomas today. The first step has been to improve the running capabilities of the little engine. To disassemble Thomas:

    1) Pry the black cab roof off of the cab. Simply insert a small screwdriver between the side of the roof and the cab and gently pry the cab roof off. A PC board with 4 wires and 2 resistors are fastened to the underside of the cab roof.

    2) Turn Thomas over on his back and unscrew the small Philips screws at each end of the wheel mechanism. Don't unscrew the flat-head Philips screw in the middle of the wheel mechanism. The wheel mechanism will separate from the body. The motor is in the body. There is no need to separate the motor from the body. The body has an umbilical cord to the wheel mechanism in the form of two wires that go from the wheel mechanism through the cab and up to the PC board that is fastened to the roof. Two more wires go from the PC board to the motor. Make sure you don't yank on these wires.

    3) If you don't need to disassemble the wheel mechanism, don't. It can be a bit tricky putting this part back together. If all you have to do is oil the wheel bearings, you don't need to take Thomas apart any further.

    4) Oiling the wheels is very easy if you have a hypodermic needle syringe. With the wheels on the ground and the white gear looking at you, you will see that the axle for the middle wheel is exposed. Drop a bit of oil on the axle. The axles at the front and at the back are readily visible if you look in the holes for the screws. Drop a bit of oil on the axles.

    5) Using the hypodermic needle syringe, the gears in the motor can very easily be reached. You don't need to disassemble anything

    6) If Thomas is stalling as you drive him through Peco Insulfrog turnouts, it's because the 6 electrical pickups are not pressing firmly against the 6 wheels. This is where you will have to disassemble the wheels - but not all the way.

    7) Unscrew the flathead Philips screw in the middle of the wheel assembly. This will release the plastic cover (containing the electrical pickups) from the wheels. As you remove the screw, hold the wheel assembly together with your hand at one end of the wheel mechanism. Alternately, lift up the other end of the plastic cover (which contains the electrical pickups). The two pickups at this end will pop out from behind the two wheels. This will expose the copper pickups for one end of the wheels. The electrical pickups (copper strips) will pop out. Bend the contacts out at the base of the pickups. Then reinsert the pickups behind the wheels. You will need to use a small screwdriver or dental pick to get the pickups behin the two wheels. This can get a bit tricky. Take your time and make sure the wheel can rotate.

    8) Repeat Step 7 for the other end. Then, using the flat-head Philips screw, fasten the plastic cover to the wheel assembly. Make sure the wheels can turn smoothly. There may be a bit of binding due to the pressure of the electrical pickups. This pressure is normal. Any other pressure isn't.

    9) To reassemble Thomas, fit the wheel mechanism over the two white plastic sprues that protude from the body. As you fit the wheel mechism onto the body, you may have to pull the wires that are fastened to the wheel mechanism into the body. Simply pull on the black cab roof. You may have to rotate the wheels a bit so that the gear on the wheel assembly will mesh with the gear on the body. Insert the two Philips screws and screw them down.

    10) Stuff the wires protruding from the cab into the cab and insert the roof SQUARELY on top of the cab. Gently press the roof into the cab. If you are having problems installing the cab roof, it's because you haven't fit the roof squarely onto the cab.

    We're not at the decoder install yet. I want to run Thomas a bit on analog to get all of the moving parts smoothed out. We'll keep you posted.

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