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Having problems speed matching any combination of these 3 engines when in a lash up.  Is there a difference in the motors or specs that would cause the speed mismatch. (Just getting used to this cab 2)   

Using conv xformer (KW) to power track  and  Legacy 990 Cab 2

Engine #1: SD40-2  2006yr  6-28257   TMCC Odyssey sys for speed cntl, 8 rpm levels, dual mtrs w momentun flywheels.

Engine #2: GP35 2014yr 6-39563  Legacy Odyssey II speed cntl, 6 official RR speeds, 8 rpm levels, Dual mtrs w m.. flywheels

Engine #3: SD60E 2015yr 6-83420  Legacy Odyssey II speed cntl, 6 official RR speeds, 8 rpm levels, Dual mtrs w m.. flywheels


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I wanted to lash up two MTH 4-4-0’s that I have.  One is the 999 with PS2 and the other is a 999 with PS3. While you would think there should be no issue with speed difference in fact the PS2 engine needed to run at 9 SMPH to match the PS3 engine running at 10 SMPH.  Before I figured this out the PS2 engine was overheating as it tried to speed up the other. (I ended up replacing the motor to make sure there would be no future problems from the overheating which produced smoke and ash deposits on the engine body near the motor vents.)

The only way to get the speed to match was to change the encoder. The PS2 engine had an encoder with 24 black stripes. 24 * 10/9 = 26.66 or rounding to 27 for the new number of black stripes.  I made up a matching encoder in PowerPoint and printed it out on paper which I then glued to the flywheel.  A test run showed both engines now happily steamed with no change in the gap between them.

Coupling the rear 4-4-0 to the leading coal car also proved difficult.  I ended up using a shaft similar to what comes attached to the cow catcher but is more securely mounted while still allowing it to pivot for curves. I only wish I had a better way to attach it to the coal car then my cobbled sheet metal adapter.

Lastly, the real reason I have two 4-4-0’s is because the PS3 engine has Scale wheels and no traction tires.  It wouldn’t pull much in spite of the engine being pretty heavy.  I bought the PS2 engine with Hi-rail wheels and traction tires to do the lash up and give better pulling performance (yes both engines have the same diameter drive wheels). I also tried Bullfrog Snot traction compound on the 2 rear scale wheels of the PS3.  I used a small flat brush to apply it very evenly in 3 moderate coats with wheels turning slow and drying in-between each coat.  Now it pulls like a champ as good as the one with traction tires.  It is still just as smooth as it runs.



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Last edited by Turbinej

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