Puffer to fan driven

The first thing that we need to know…..WHAT ARE YOU WORKING ON!!….fellas, we can’t help you if we have no idea what’s the make, model, and product number!…

Pat

For you newer folks, …use this as an example, in your subject title, it’s helpful to have an item number, and a brief description of the issue you’re trying to tackle,….it helps all the techs to identify the model, look up parts, TSB’s etc,…to help you,…..I’ve circled how it should look for others to assist y’all!…

Pat

First off, thanks for not blasting me too far out of the water for not using the proper protocols.

I’m working on a Polar Express engine # 1225. This is a ready to run set 6-84328, so I don’t have the engine exact information. It was first featured in the 2017 ready to run set catalog on page 26. Unfortunately I don’t have too much more information.

let me know if any other info is needed.

Interesting. Its a photo interrupter, or non contact switch. First time I have seen these used in this application. I don’t see you being able to use it with fan smoke unit as its the puffer piston lever that breaks the beam. All that would have to go if you did an upgrade. John's chuff generator is likely your best bet here. You could change the cam and use a micro switch though but nowhere as easy.

Pete

@O G Beginner STL posted:

First off, thanks for not blasting me too far out of the water for not using the proper protocols.

I’m working on a Polar Express engine # 1225. This is a ready to run set 6-84328, so I don’t have the engine exact information. It was first featured in the 2017 ready to run set catalog on page 26. Unfortunately I don’t have too much more information.

let me know if any other info is needed.

Wasn’t blasting you one bit, ….but the fellas can’t help you if they can’t tell what you’re working on,….the info you’ve provided now is perfect,….just keep that in mind when asking service questions,…..you’ll get a lot further that way,….

Pat

So, the photo sensor is reading the piston and that is controlling the puff in the smoke generator and the chuff sound? I’m not sure I’m clear on what the photo sensor is reading. As I move forward I want to know what the output from my current board (photo sensor) actually represents.

There is a lever that is pushed up and down by an axle cam. The rear of the lever interrupts the IR beam in the sensor and sends a signal to chuff input for the sound. The front of the lever moves the smoke piston up and down to push the smoke out the stack.

Pete

Ah ha, so all I really need to do is pull out that crap and use the reed switch to feed the super chuffer and the old board. The super chuffer can control the fan smoke right?

No, you can use the current optical to feed both your existing sound board AND the super chuffer. And yes, like the name suggests it's job in life is to chuff a fan - aka control,run, and power a 5V tiny fan motor in a smoke unit.

It's output from the optical sensor is 5V high, and then 0V low when chuff- the same signal the super chuffer is looking for.

All you would do is possibly cut off the front part of that lever system (obviously after where it interfaces the cam on the front axle) or just ignore it completely and ensure it has clearance to move up and down.

It really depends on where the fulcrum is on the lever that determines if you can use it as your chuff switch. Leaving it on may or may not make it harder to fit your fan smoke unit. Pull off the puffer to see if its possible to keep it.

How many chuffs per driver rev are you getting now? If it isn’t 4 thats another reason to go in another direction.

Pete

FWIW, I did a conventional series II Polar Express upgrade to full command and fan driven smoke.

And another reason to go in another direction, ….the puffer unit is also the return mechanism for the lever….with the puffer unit gone, the piston and piston spring gone, you’ll have to fabricate a way for the lever to return to the base circle of the cam lobe, otherwise, it might ride up to the top of the lobe and just stay there……or jump around and give you erratic chuffs, and puffs of smoke …..

Pat