While we are on the subject of Atlantic issues - rapid chuff

Just curious.  How many chuffs per revolution is it doing?

At slow speeds - normal - At higher run speeds

hard to count - But, does sound like skipping is also happening in rapid chuff. Why, do you ask?

I am not aware of any engines that have dual triggers. They either have a mechanical switch or a signal is generated off a tach sensor on the motor flywheel. DCS, TAS, and most Legacy use the latter. TMCC and Legacy with back emf uses a switch.

Pete

@shawn posted:

A shout out to Mike Regan - If he is still around. There's been many mentions of rapid machine gun chuff on the atlantic  steamers. Many have mentioned the chuff switch adjustment. But, I think it goes beyond the chuff switch.

I mentioned this issue to mike regan at York a while back. I'm pretty sure I understood his response clearly? I believe he stated the microsowitch is only used for the intial chuffs when starting. Then there is a signal on the motor sensor board that takes over. I believe John's smoke puff generator functions similiar?

I would really like to find out if this is the case. As, I have one or two units there is no way its the microswitch. IMHO

I have no idea what version of the Atlantic steamer Mike was talking about, but I've personally never seen one with the chuff switch that didn't use it to generate all the chuffs "except" the first.  TMCC and early Legacy used the mechanical chuff switch, when the RCMC came along, the chuff was generated from the tach reader and there was no more chuff switch.

The Railsounds boards in products that have the physical chuff switch actually generate the very first chuff, at least from a power up, it does that when it sees a initial motion command.  You can tell, the symptom for a broken wire or dead chuff switch is a single chuff as you start and then never again.

@shawn posted:

At slow speeds - normail - At normal run speed hard to count - But, does sound like skipping is also happening in rapid chuff. Why, do you ask?

@shawn posted:

...I believe he stated the microsowitch is only used for the intial chuffs when starting. Then there is a signal on the motor sensor board that takes over. ...

I thought maybe both were providing a chuff signal at the same time and you were getting twice the chuffs (you had an 's' on "initial chuffs").

While not related to your question, the drive wheels on my 0-4-0 are small, and it sounds like a machine gun unless it is running real slow.   

@CAPPilot posted:

I thought maybe both were providing a chuff signal at the same time and you were getting twice the chuffs (you had an 's' on "initial chuffs").

I never saw or even heard of a locomotive that had both the mechanical chuff switch/cam and also generated chuffs from the flywheel tach, I'll be astonished if you can find one! As I said before, the single initial chuff is the only "generated" chuff I know of from the electronics for locomotives with a mechanical chuff switch.

I did have one guy that installed my Chuff-Generator and couldn't figure out why the chuffs were all scrambled!   Clipping the lead from the chuff switch yielded redemption.

@gunrunnerjohn posted:

I never saw or even heard of a locomotive that had both the mechanical chuff switch/cam and also generated chuffs from the flywheel tach, I'll be astonished if you can find one! As I said before, the single initial chuff is the only "generated" chuff I know of from the electronics for locomotives with a mechanical chuff switch.

I did have one guy that installed my Chuff-Generator and couldn't figure out why the chuffs were all scrambled!   Clipping the lead from the chuff switch yielded redemption.

John.

I agree - But, I 'm sure that is the way his response went to my question. That's the reason for me asking. Hopefully - we can get word from Mike Regan.

I may not have the depth of experience with TMCC and Railsounds as Mike, but I know my way around these products pretty well.  I've worked on hundreds of TMCC/Legacy engines, and I've never seen what is being described.  Add to that it makes no sense to duplicate a tach reader chuff generation with a physical chuff switch, and I'll be really surprised if there is such an example.  For sure, commonplace it ain't!

@shawn posted:

A shout out to Mike Regan - If he is still around. There's been many mentions of rapid machine gun chuff on the atlantic  steamers. Many have mentioned the chuff switch adjustment. But, I think it goes beyond the chuff switch.

I mentioned this issue to mike regan at York a while back. I'm pretty sure I understood his response clearly? I believe he stated the microsowitch is only used for the intial chuffs when starting. Then there is a signal on the motor sensor board that takes over. I believe John's smoke puff generator functions similiar?

I would really like to find out if this is the case. As, I have one or two units there is no way its the microswitch. IMHO

Do you have a link to a recording or a video of this problem?  I'm curious what it sounds like.

@shawn posted:

I would really like to find out if this is the case. As, I have one or two units there is no way its the microswitch. IMHO

Perhaps if you would tell us the exact product numbers of the affected units it would be a big help.

@rplst8 posted:

Do you have a link to a recording or a video of this problem?  I'm curious what it sounds like.

no - the engine is currently in storage. I own a lot of Atlantic's. One was the cherry switch - not chuffing at all. I remove the motor with the shell off so I could push by hand with power on. really helped - that one was chuff switch. The one with rapid chuff skip - I've changed the switch. The issue still persist. I always wondered if the axle blocks are not completely square that fit in the frame - Maybe, they are not orientated correctly. Hopefully, I can get it out of the box for a video.

@gunrunnerjohn posted:

Perhaps if you would tell us the exact product numbers of the affected units it would be a big help.

i believe a 6-11117 santa fe 1484.

Well, I can tell you with 100% certainty that one does NOT drive the chuffs from the tach reader.  I've had several of them in for service, and the chuff switch was the most recent.

@gunrunnerjohn posted:

I may not have the depth of experience with TMCC and Railsounds as Mike, but I know my way around these products pretty well.  I've worked on hundreds of TMCC/Legacy engines, and I've never seen what is being described.  Add to that it makes no sense to duplicate a tach reader chuff generation with a physical chuff switch, and I'll be really surprised if there is such an example.  For sure, commonplace it ain't!

John,

Actually there were quite a lot of Pre-RCMC Legacy Locos that had a physical chuff switch, and those locos also used the motor encoder to pace the chuffs.  Once the switch made a single contact, the next 3 were generated from the tach feedback.  The backstory is the 4-lobe CAM was not perfectly lobed at 90 degrees, and yet we wanted to sync the driver wheels (hence the piston) at a certain relationship to the chuff sounds with a CAM.  Using the tach to pace the 4 chuff times, we could satisfy Neil Young's expectation of properly timed chuff sounds when the CAM lobes were not perfectly formed.

@SantaFeFan posted:

John,

Actually there were quite a lot of Pre-RCMC Legacy Locos that had a physical chuff switch, and those locos also used the motor encoder to pace the chuffs.  Once the switch made a single contact, the next 3 were generated from the tach feedback.  The backstory is the 4-lobe CAM was not perfectly lobed at 90 degrees, and yet we wanted to sync the driver wheels (hence the piston) at a certain relationship to the chuff sounds with a CAM.  Using the tach to pace the 4 chuff times, we could satisfy Neil Young's expectation of properly timed chuff sounds when the CAM lobes were not perfectly formed.

Wow, learn something every day.  I guess I was fooled into thinking when the chuff switch didn't work you got zilch, so it never occurred to me that the two were combined!  Since the cam indeed has 4 lobes, that really is a something! A dumb question, how did you insure you were using the right lobe on the cam to start the timing?

That was taking realism to another level with synchronizing the position of the driver to the chuff, how come they abandoned that with the RCMC?

I stand (or rather sit) corrected!

@gunrunnerjohn posted:

Wow, learn something every day.  I guess I was fooled into thinking when the chuff switch didn't work you got zilch, so it never occurred to me that the two were combined!  Since the cam indeed has 4 lobes, that really is a something! A dumb question, how did you insure you were using the right lobe on the cam to start the timing?

That was taking realism to another level with synchronizing the position of the driver to the chuff, how come they abandoned that with the RCMC?

I stand (or rather sit) corrected!

So, the motor sensor board could be an issue? How were the chuffs from the sensor derived?  is there a connection from the motor speed sensor to the sound card? If I believe this is my issue. What is the scope to trouble shoot the issue? also, does this still mean I will get chuffing if the switch is disabled. Or, does it need to be activated one time with the motor running?

What if the switch is bouncing? intermittent on contact cam closure. I assume that doesn't matter because the first closure occurred. So, the issue would have to be something other than the switch?  Also, was a resistor added at some point to correct this issue. I believe that was mentioned in my travels...

@gunrunnerjohn posted:

Wow, learn something every day.  I guess I was fooled into thinking when the chuff switch didn't work you got zilch, so it never occurred to me that the two were combined!  Since the cam indeed has 4 lobes, that really is a something! A dumb question, how did you insure you were using the right lobe on the cam to start the timing?

That was taking realism to another level with synchronizing the position of the driver to the chuff, how come they abandoned that with the RCMC?

I stand (or rather sit) corrected!

This issue has been driving me insane!!! That's all I can say! I assume he's saying any pre- rcmc board with4 lobes cam and legacy? It would be nice to have a list of engines that incorporated this feature.

That's a @SantaFeFan question I would imagine, I'm not sure where they are coming from.  I guess if the serial data goes through the DCDS, the output on pin-2 of the 10-pin connector could insert the chuffs.   Since they're coming from the tach counts, I suspect that might be the way it's done.

I found this diagram, the chuff switch seems to be directly connected to the smoke unit.  Not sure how that could work if the switch was closed and you wanted to generate a chuff from the DCDS.

Here's another early Legacy wiring diagram, seems like it's wired the same way.  You'll have to wait for Jon to describe how the chuff got back to do the smoke chuffs, I'm not seeing it from these diagrams.

Lionel Legacy FEF3 Wiring Diagram.pdf

See, that 1k resistor off the chuff switch. I'm thinking that is missing. or, it was added later at some point? I certainly don't remember seeing it. At least in the wiring to the chuff switch? although, I may have removed. If it was in line in heat shrink. Going to be interesting to find out.

John,

If you have your Atlantic in pieces what's the value of the capacitor across the chuff switch?

@shawn posted:

John,

If you have your Atlantic in pieces what's the value of the capacitor across the chuff switch? Also, I think he stated that 1 closure of the chuff switch produces the next 3 chuffs using the tach. I assume this continues and it is never completely the tach. Is that your understanding?

@gunrunnerjohn posted:

Wow, learn something every day.  I guess I was fooled into thinking when the chuff switch didn't work you got zilch, so it never occurred to me that the two were combined!  Since the cam indeed has 4 lobes, that really is a something! A dumb question, how did you insure you were using the right lobe on the cam to start the timing?

That was taking realism to another level with synchronizing the position of the driver to the chuff, how come they abandoned that with the RCMC?

I stand (or rather sit) corrected!

With a 4 lobe cam correctly positioned it wouldn't matter what lobe they started with, they would all be in the correct position. It really begs the question why move from the cam to the tach reader? The cam is always spot on assuming it had 4 perfect sides.

Another solution looking for a problem.

Pete

@shawn posted:

John,

If you have your Atlantic in pieces what's the value of the capacitor across the chuff switch?

It's in a box waiting for parts to build it up.

@Norton posted:

With a 4 lobe cam correctly positioned it wouldn't matter what lobe they started with, they would all be in the correct position. It really begs the question why move from the cam to the tach reader? The cam is always spot on assuming it had 4 perfect sides.

Another solution looking for a problem.

Good point Pete, I thought of that after I posted.

I didn't quite understand the issue that prompted the two-pronged approach either, that seemed like a lot of extra work.

I guess Santa Fe fan hasn’t seen this post yet. Getting ready to reopen the engine and take a look - John, do you think he meant the first closet of the cam switch - the motor tach took over from there on out.

Actually, he means every 4th cam closure starts a new cycle, one chuff from the cam and three from the electronics, timed from the flywheel, then the next chuff comes from the cam again.

@gunrunnerjohn posted:

Actually, he means every 4th cam closure starts a new cycle, one chuff from the cam and three from the electronics, timed from the flywheel, then the next chuff comes from the cam again.

Ok - that’s what I initially thought - sort of crazy. So, I wonder if there most be a hold off time from the cam being detected again before the 3 chuffs are complete??

Well, I thought about that, but if the electronics has the correct gear ratio, it shouldn't be a problem, they're measuring actual rotation of the flywheel.

OK, I think I know why they went with this setup. I don’t believe there is a cam on an axle. Looking at the frame I see no cam. I am guessing the switch is closed by one of the crossheads like a post war engine. That would give one chuff per revolution.

Pete

@Norton posted:

OK, I think I know why they went with this setup. I don’t believe there is a cam on an axle. Looking at the frame I see no cam. I am guessing the switch is closed by one of the crossheads like a post war engine. That would give one chuff per revolution.

Pete

Depend on the vintage of the engine - the 1484 Santa Fe -  6-11117 definitely has a cam . On the axle It buried —

@gunrunnerjohn posted:

Well, I thought about that, but if the electronics has the correct gear ratio, it shouldn't be a problem, they're measuring actual rotation of the flywheel.

Or, he wasn’t clear and just describing the first sequence - 1 chuff switch 3 chuffs motor tach. Maybe the switch just starts the sequence and the motor tach takes over completely.

Whatever.  I read it that they used every 4th switch closure, but maybe someday I'll check it out and see what happens.

@gunrunnerjohn posted:

Whatever.  I read it that they used every 4th switch closure, but maybe someday I'll check it out and see what happens.

I’m going to try and pick mine up from my mansion over the weekend - I’ll let you know what I find.

@gunrunnerjohn posted:

Whatever.  I read it that they used every 4th switch closure, but maybe someday I'll check it out and see what happens.

GRJ, that is correct.  I can't vouch for the wiring diagrams, but know for sure the very first Legacy Loco (Big Boy) used the CAM to puff, and start the Chuffing sequence.  It was not a solution looking for a problem.  The CAM symmetry was hard to maintain in production, and Legacy was a high bar.  Since we had the chuff switch and the tach, the software to create the timing was quite simple.

@SantaFeFan posted:

GRJ, that is correct.  I can't vouch for the wiring diagrams, but know for sure the very first Legacy Loco (Big Boy) used the CAM to puff, and start the Chuffing sequence.  It was not a solution looking for a problem.  The CAM symmetry was hard to maintain in production, and Legacy was a high bar.  Since we had the chuff switch and the tach, the software to create the timing was quite simple.

Makes sense I guess if the cam wasn't doing it.  How did the succeeding chuffs get fed back to the smoke unit logic?  I didn't quite get it from the wiring diagrams I saw, though they may not be correct.

@SantaFeFan posted:

GRJ, that is correct.  I can't vouch for the wiring diagrams, but know for sure the very first Legacy Loco (Big Boy) used the CAM to puff, and start the Chuffing sequence.  It was not a solution looking for a problem.  The CAM symmetry was hard to maintain in production, and Legacy was a high bar.  Since we had the chuff switch and the tach, the software to create the timing was quite simple.

So, Jon - the Switch was basically smoke puffing and the motor driver board took over completely after the first closure for chuff sound?

which, might make sense why one person change the r4lc and corrected the issue. At, least in his case. The other question - did that sound chuff signal go into the duty cycle input on the R4lc or chuff input? Where was the signal coming from.
we need a wiring diagram.

Quoting GRJ,

"I read it that they used every 4th switch closure, but maybe someday I'll check it out and see what happens."

This is correct. -jon

@shawn posted:

A shout out to Mike Regan - If he is still around. There's been many mentions of rapid machine gun chuff on the atlantic  steamers. Many have mentioned the chuff switch adjustment. But, I think it goes beyond the chuff switch.

I mentioned this issue to mike regan at York a while back. I'm pretty sure I understood his response clearly? I believe he stated the microsowitch is only used for the intial chuffs when starting. Then there is a signal on the motor sensor board that takes over. I believe John's smoke puff generator functions similiar?

I would really like to find out if this is the case. As, I have one or two units there is no way its the microswitch. IMHO

Shawn, do you have this engine? If so, any chance of making a video. It appears the thread was started because the chuff rate does not sound like a normal 4 chuff per rev  engine.

Pete

@Norton posted:

Shawn, do you have this engine? If so, any chance of making a video. It appears the thread was started because the chuff rate does not sound like a normal 4 chuff per rev  engine.

Pete

Pete,

I came into procession of like 5 or 6 of these atlantics in different flavors - via a eBay blowout. Two whistle smoke versions and three non whistle smoke. I kept two and gave the others away to my nephews kids.

The suspect unit is at my nephews house. When, I get over there. I would be glad to make a video.

I really wish Lionel had a wiring diagram for the 6-11117 Santa Fe 1484 Atlantic

shawn