Problems with brand new DCC-Sound SD45

[spookshow]

I would try to add some capacitance to the circuit. I've shown how to do this in another forum. You should Google it.

This thing already has two giant capacitors on it - you'd think that would be enough.



Cheers,
-Mark

[gatrhumpy]

Well, that's not very much capacitance, even though the size is huge. It's only 200uF worth of capacitance. I can get 220uF in about a quarter of the size. In fact, I would be willing to be that replacing those capacitors with smaller ones and adding more capacitance could make these sweet runners.

However, the height of the shell is a deal-breaker to me.

[spookshow]

Capacitors may help with the symptoms, but don't really address the main problem. Trouble is, I can't for the life of me figure out what that problem is. At this point I'm starting to get suspicious about the motor (or perhaps how the decoder and motor work together). I'm half tempted to rip out the decoder entirely to see how it runs under straight DC, but then I wouldn't be able to return it.

Cheers,
-Mark

[gatrhumpy]

Mark, I have run this on DC, and it runs perfect. I ripped out the decoder myself and no pickup issues whatsoever. So what it's doing, it's because of the DCC decoder/lack of capacitance.

[spookshow]

I seem to have gotten somewhere, but at this point I'm not entirely sure what I've learned...

I really wanted to give this thing some lengthy break-in time, but with all the stalling that just wasn't possible. So, my bright ideas was to crank the base voltage on my DCC system way up (from 16V to 20V). This allowed me to run the locomotive fast enough that it would power through the stalls. And, lo, I was finally able to run it around in circles for many hours (both forward and reverse).

Initially there was a lot of unevenness (up and down RPMs), but eventually (after about 8 hours in either direction), performance smoothed right out. But then a new problem - loud screeching when moving in forward (but not reverse). I checked the guts and it didn't appear that there was any lubrication at all. So, I greased the gears and oiled the bearings and it quieted right down.

At this point it runs perfectly. But the big question is - why? The most likely culprit would seem to be the wheel blackening (which eventually wore off). But man, that's a lot of hours for wheel blackening. Also, wheel blackening has to go somewhere (IE the track), and usually when going through this process I wind up having to clean the track at least once to get the loco running properly. But not so in this instance - I haven't had to clean the track at all.

What's odd is that after breaking it in in forward to the point that it ran pretty well, it still ran just as poorly in reverse as it did before. And only after breaking it in in reverse did performance improve in that direction. And if it was a wheel blackening issue, I wouldn't think that direction of travel would matter.

Do motors need break-in periods? I've never heard of that before, but who knows with these new coreless motors. Maybe that's a thing now?

Any thoughts?

Cheers,
-Mark

[gatrhumpy]

It never occurred to me about the wheel blackening. That's just **** poor QC, IMO. If Bachmann wanted to make a great sounding engine that people will love, lay off that crap! People don't know what's wrong with it when it keeps stalling.

So it seems like the stalling stopped after you ran it around the track for more than 8 hours to get the wheel blackening crap off. It seems like people could do the same thing by running it through a wheel cleaner with brushes or using a new Brite Boy on it. This would allow the lubrication to stay on the gears and eliminate the screeching noise you heard.

I've heard that motors need break-in period, but, well, being an engineer, don't see the justification for needing one.

I'm glad that you figured it out Mark. Now if they could do something about the awful height of the thing in respect to the frame.

[spookshow]

It could be the wheel blackening - but the fact that it started running pretty good one direction but not the other kind of leads me to believe that it wasn't. You'd think that performance would uniformly improve in both directions if wheel blackening was the issue.

Cheers,
-Mark

[westfalen]

We will test some on this end to determine if there is a problem.

It's now six months.  Any results from the tests yet?

[Bucksco]

Call the service department - the problem has been solved.

[gatrhumpy]

What was the problem?

[Bucksco]

Not exactly sure but I believe it has a newly designed contact strip.

[gatrhumpy]

You mean the four sticky upper wipers on (two on each truck) are no longer there or they've been redesigned?

[Bucksco]

I was told that the power pick up plate was redesigned - haven't seen one first hand. Next time I visit the service department I will have to check it out.

[spookshow]

I ordered a set of replacement trucks from the service department (the parts department doesn't have them, or apparently even know about them). Will be interested to see how they work.

-Mark

[westfalen]

Thanks, will contact the service department tomorrow.