3-rd Rail CP D10 - Chuffing Problem

I can't see your image.  The 3rd rail site suggests the engine uses Railsounds 4.0 steam hardware.  If this is what you have, what's connected to the "trigger" connection per following from RS4 manual?

They usually have a cam on a drive axle for the recent 3rd rail stuff, so the chuff would be logically going to ping 17 of the R2LC and then to the sound board over the serial data link.  Not sure what this one uses, I can't see the picture either.

Thanks, Stan and John. Just reposting to hopefully make the image visible. Of course it's visible on my monitor, although misplaced in the text??

We need a picture of the trucks on the tender to see if that's where the chuff generation is done.

Seems nothing but a ground strap and the hot shoe visible? No magnet nor reed switch which is what made me go looking inside the engine for something??

It's obviously being done in the locomotive, my guess is the chuff switch on the driver axle needs adjustment or replacement.

Thanks, John.

I wiggled the chuff switch back and forth from the 2chuff-4chuff position, as I've done before. Now, no chuffs . . . which is actually an improvment over the un-synch'd cacaphony of random chuffing I was getting. I notice too that the smoke no longer "puffs," just a steady stream of vapor now. Not really sure what can go wrong with a simple toggle switch? They either work . . . or no?

The switch may simply be bad, have you tried contact cleaner?

BTW, there are two microswitches on the axle cam to select two or four chuffs, one or both of those may be giving you issues as well.

Thanks, John. No contact cleaner. Shot a little WD-40 into it and excercised the switch. To no avail.

The wires leading from the chuff switch disappear down into the bowels further than I'm prepared to diasassemble this little critter. I guess the cams you refer to are down in there too. Can't see anything in there. All closed up. It chuffed fine in reverse for a few yards. Went forward and chuffing stopped. Reverse again and no chuffing.

I have a reed switch and magnet left over from an ERR kit. Might have to resort to that.

Yes, the cams I speak of on the 3rd Rail are on a driver axle, so by definition, they're at the bottom under everything.   Obviously, the switches are down there with the cams.

Wait a few weeks and I'll have an easier solution for you.

It's in the production queue now.  I've been using prototypes of this on my conversions for several months, no magnets, reed switches, etc.  It'll do any number of chuffs, and you calibrate it exactly to the specific locomotive in question, so gear ratios and the like are not an issue.  As  bonus, my production model is going to have an optional ground light feature that will control ground lights and turn them off at around 10 scale MPH.

Sounds promising, John.

Not sure there'll be room though? Looks like you have a tach strip on the flywheel with a reader atop the motor? Room is really tight on this little thing.

Yep, I use the tach strip as a convenient way to tell how far I'm moving, just count the stripes.  I've put these in some fairly small units, including the MTH Camelback, that was a pretty tight fit.  I did make the production boards .031 thickness vs. the .062 you see with the prototype boards.  I'm still working on a couple of mounting base issues, basically how to make a bunch of them without breaking the bank.

The actual thickness of the production boards from the top of the components is only 3/32" plus whatever the mount adds, usually another 1/32".  So if you have a bit more than 1/8" clearance, it should fit.  It can also be mounted anywhere on the motor, doesn't have to be any particular orientation, just have to have the sensor end over the flywheel.  Sometimes the flywheel diameter dictates additional spacing from the motor, that may be more of a problem than the thickness of the board.

GRJ,

How hard would it be to divide the board so the optical sensor is mounted separately and the rest of the electronics are fit somewhere else?

My first candidate for install is Weaver A-5 0-4-0. 

One thing that I actually did with one of these was to make a little perf-board with the sensor on it and just extend the four wires from the sensor holes to the little board. I was actually putting this into a decent sized locomotive, but the way the motor sat I couldn't find any place to put the full board.  I could probably lay out a simple board with just holes for the sensor and the wires, that would work.  Funny thing, I have the K-Line A-5 with TMCC, and I'm wanting to put fan driven chuffing smoke into it.  I may have to resort to something like this to get the job done.

Interesting idea, I'll give it some thought.