Record & Playback: Variance, all of a sudden. << SOLVED >>

Check the SF for a thrown traction tire

Alex,

   Barry is right on the money, any adverse drag such as a binding traction rubber

tire, can alter the actual distance your engine is traveling. 

PCRR/Dave

Barry, Dave -

Looked at the tires of both A units, and all are there. They are rather shiny as I have never changed them. The odometer reads 521 scale miles, but I have no clue of what the longevity of the tires is, or whether this reading could have been affected by repairs done about two or three years ago.

I am going to check the track to see if there is anything that could have caused the wheels to slip. About a fifth of the dual main (some 50 to 60 feet) is hidden, and although accessible, is not just as convenient to reach, so I have not even wiped it off in four years - I guess I better do it now .

If you can think of anything else, please let me know.

Thanks!

Alex

Alex,

    Even a change to a skinny tire that slips on an intermittent basis, might change the travel, you might have to reprogram to use the new skinner rubber tire.  Best to find the same size tire you removed, and install it.  Then retest the Record & Playback program.

PCRR/Dave

Just guessing but maybe the rolling stock is do for lube job? and or track wipe down?

Clem k

clem k,

    There is an outside chance a lube job could help, however lack of lub should not make the engine run quite this far off, your advise is good however I would additionally lube the engine just incase, he might be really binding as the engine travels.

PCRR/Dave

Worse than anticipated - - - 

After cleaning the track and changing the tires on both A units, it was time to test the ABA locomotives without the cars. They ran fine in reverse, but when running forward, the front truck of the trailing A unit; that is, the truck that is closest to the passenger cars, did not run, and was forced or tilted upwards while it was dragged. 

The entire ABA appears to run OK from a distance, but it is struggling. I am surprised that it ran at all the last few times and that it appeared to be OK. If it had not been for being short three feet of the end point on the Record/Playback session, as I described earlier, I may have never known.

I have another group of guests coming in two hours, so I don’t think I will have time to investigate what is wrong with the trailing A unit. I am going to replace the SF passenger train (my favorite) with a similar MTH ABA Union Pacific passenger train – my very first O-Gauge acquisition in 2008 (from Jimmy Sutter) and try to duplicate the Record/Playback session I have that includes the SF passenger train.

Question abort the Record/Playback feature:

I have two TIU’s, and they are in Super Mode. Is it possible to record three sessions on each TIU? I ask because the session in question (with the SF train) is TIU1, Session 1, and I have two other sessions on TIU1 that I would like to keep. It would be nice if I could record the new session, using the UP train instead of the SF, on TIU 2.

Thanks!

Alex

Short answer  No.  You only have 3 sessions in super.

Alex,

If you substitute anther ABA for the problem unit, and if it's the same size, you might get away with simply renumbering its DCS ID to that of the problem unit and use the same Record/Playback session.

I haven't ever tried this, however, it should work.

Good idea. I think it will work also. Since it goes by IDs

I have done what Barry has suggested. It worked well, within reason, using the same engine with a different road name.

With mine, I made sure the settings were the same. I'm not sure if that makes a difference or not. By settings I mean Smoke volume, deceleration rate, etc. The result was pretty good.

On the other hand, I've found that recording for super accuracy is pretty tough so I try for reasonable accuracy. Setting up the scenario so it's not too critical where it stops seems to help somewhat. (if you need to clear a switch for example, don't clear it by one foot, clear it by 3 or 4 feet if possible)

Thank you, Barry!

As others have attested, changing the engine ID does the trick. I deleted the SF ABA (ID=23) and changed the UP ABA from ID=1 to =23, and the session ran fine. The UP ABA ran about two feet over, but considering that it is a different ABA set, it was not bad at all.

I had no time to test the session with the substituted passenger train before our guests arrived, so they witnessed the test-run. Consensus: A-OK.

The SF+BNSF freight train keeps returning to the start point ±1 inch. Out of four runs today, two were one inch shy, one about an inch long, and the last only 1/4-inch short.

Next thing to do is to figure out what is wrong with the trailing A units 'dead' truck. I have not taken it apart yet, as our guests left a short while ago.

Thank you all for your help!

Alex

Alex,

   Looks like you have this problem licked, you may need some new trucks of the unit

however.

PCRR/Dave

<SOLVED>

The reason for the Santa Fe F3 ABA passenger train variance was due to the trailing A-Unit. The leading truck of this F3 was not operational when the ABA unit traveled forward; it was just dragged along. I suspect that this occurred intermittently, and it progressively became worse.

I sent both A units to George (GGG) last week, he worked his magic, and I had the locomotives back this past Tuesday! Talk about speedy service!

This was soon enough to allow me time to record a new session including the Santa Fe passenger train, and add a few operations that I had thought of in the meantime.

Everything worked out great, we had 24 guests visit us Thursday, and we had a great time. Since the Rural Missouri article was published a few weeks ago, we have had 55 guests, to bring the total of our signed-in guests to 232.

Bottom line – Thank You George!

Alex

Your Welcome.  G