Upgrading to 4 chuffs and new smoke unit

1.  Yes it is

2.  Go to Lionel's web site and search the videos for modifying ( rebuilding) a smoke unit.

doug

2. It depends on how they control the smoke unit, what does it do now while standing?  I'm presuming this is a fan driven unit, right?

Thanks Guys,

I believe it's a fan driven unit.   However, produces no smoke at rest.   So does one modify the existing smoke unit or replace it with one that emits smoke when standing still?

It's not the smoke unit that's at fault, it's the control for the fan.  It sounds like the chuff control only runs the fan for a chuff.

What's the exact model of the locomotive?

(6-38053)   I believe it's from 2003

http://www.youtube.com/watch?v=C7uA4fhrAa8  is a video of it running.

Contact Alex - He's the 'guru of smoke & chuffs'

Heres a link to Alex's upgrade thread.   https://ogrforum.ogaugerr.com/d...ent/7906207229853027

Making the sound board produce 4 chuffs is not too difficult using a reed switch and magnets on a tender wheel. The challenge is to synchronize those 4 chuffs with the smoke unit. This engine does have a fan driven "semi smart" smoke unit. A micro switch activated by a cam on a driver axle is what drives it and chuff sound. If wanted to avoid reinventing the drive electronics, modifying the axle cam to 4 lobes would achieve what you want and give synchronized chuffs. 

Pete

Again, many thanks to all,

Pete...Thanks for letting me know that an axle cam triggers the chuffs and the smoke.  Now what can be done, if anything, to have the smoke unit put out smoke at idle?

Steam, Does the smoke unit send out steam in "chuffs" or is it just a steady stream when the engine starts to move? If its the latter than an additional circuit might have to be constructed so the chuff switch does trigger the fan. I will check my schematics when I get home to verify what triggers "semi smart" smoke units.

Pete

Pete.....individual puffs when starting.

If I recall, the first issue of the scale Berkshires where the same way.  No smoke while standing, only when moving.  At the time the cure was to put in the TAS Chuf and Puf unit..But don't know where the surplus of these went to, they were great units...

Marty

ERR has a similar item that may solve the problem, it's a new product.

gunrunner john:  do you know what product of theirs will work in this application?

I took a look, and it's only for use with the Cruise Commander, so it probably won't do the job for you.

Good news at least if you modify the cam. You should get 4 synchronized chuffs but you would probably have to build an additional circuit to drive the fan at standstill. The trick would be to disconnect that extra drive voltage when the engine started to move.

Pete

How does one add modify the cam to get 4 lobes?

Its not easy but others have removed the axle and applied epoxy 90 degrees to the existing lobes. I am working a different scheme to achieve the same effect using an optical detector aimed off one of the drivers which has 4 white lines painted on it. It works but I just have shrink the circuit down to fit in the small engine (2-8-0) I want to put it in.

Pete

A simple delay circuit will allow you to run the fan at rest, and disconnect when you start moving. 

One concern I have with modifying the cam is how long the modified lobes will last with continual rubbing of the microswitch arm.

How small do you think you need the circuit for the optical detection, I don't see any need for it to be that large.  Being lazy, I'd probably build it to use one of the really tiny 2A relays that I use for other smoke circuit mods.

The detector circuit is small but the 5 volt supply to drive the fan is using most of the space ~1" cubed. This engine had a conventional puffer.

Pete

Just curious, why so much space for a 5V supply?  You can drive the fan with a TO-92 5V regulator, small cap, and a bridge rectifier.  I also find if I make the circuit flat, it fits in a lot more places, even if it's larger in surface area.

I hope you are not simply applying rectified 20 VAC to your regulator. I am using one of the new switching regulators which are designed to replace the 7805s but can be driven by over 20 volts and not die. Unfortunately they are larger than a 7805. The 5V is also used for the detector circuitry.

Here you go.

Pete

If you're running command only, you can use a diode instead of the bridge to cut down the input voltage.

Those modules seem overkill for the job, not to mention expensive, 10 watts?

The specs I see are 18 volts max input voltage.