Atlas Alco 424/425

[Anonymous]

I need guidance on removing the body on my loco in order to install a decoder. I've gotten as far as finding the mounting tabs and trying to lift the body off but something is stopping the body from lifting off completely. Any suggestions?

[Anonymous]

Try checking for wire conecting the trucks to the constant lighting board. And be sure that it does not already have a atlas decorder.

[nfmisso]

Hi Jim;

You did not specify if this is a new Atlas Classic release or the older Atlas/Kato release. I do not know if there is a difference. The following works for the Atlas/Kato units.

1. gently pull the hand rails out of the cab.
2. gently tug on the cab, pulling it straight up.
3. squeeze one end of the body inwards to release the tabs, and pull that end up slightly.
4. repeat for the other end.
5. pull off the walk way. (this is probably different on the Classics.

On my Atlas/Kato units, I changed to Kadee #5, and built up a plastic pad on the frame to be snug with the top of the Kadee box. The box has to be trimmed slightly to fit in the opening. I then broke off the body mounting tabs and cemented the body to the walkway. After everything is solid, I slipped the body onto the chassis, then slide the assembled #5 into the opening in the pilots, and installed the original coupler pin to hold them in place. Now to remove the shell, I have to pull two pins, and slide out the two assembled couplers - works great.

The big reason to bond the shell and walkway together is the bending walkway problem with the Altas/Kato RS3, RS11, RSD4/5, RSD12, C424 and C425 which results in the couplers going upwards when pulling heavy loads. With the above modification, the walkway is 100X stiffer in bending, and the metal chassis thru the pads that are against the top of the Kadee box will not let it bend either.

Bending stiffness is proportional to thickness cubed, so a 5X increase in thickness results in a 125X increase in stiffness (125 = 5 cubed).

[nfmisso]

QUOTE: Originally posted by CNWfan5525

Try checking for wire conecting the trucks to the constant lighting board. And be sure that it does not already have a atlas decorder.

Atlas has never offered an HO scale C424 or C425 with a factory installed decoder.

PS I used a NCE DA-SR, works great, super fast install.