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Old 09-11-2019, 03:46 AM   #11
gimme30
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Well GNfan you nailed it! Since the 0-6-0 has been relegated to shelf duty I decided to go ahead and take it apart and sure enough a tiny chunk of white plastic fell out when I took off the shell.
I really liked that little engine, even though it couldn't pull more than 2 or 3 cars downhill with a tailwind. I don't know that I'll repair it though...all those tiny little parts! They're cheap enough that if I decide I can't live without it I'll just buy another one.

TF I tried getting pics but my little point-and-shoot can't focus well up close. I'll try again under better lighting this weekend, or use the cell phone camera. Boy do I regret selling off all my 35mm gear now!

In the meantime I'll try to be more specific. Both engines are made by Bachmann, one is an RS3 and the other a GP7. Both are dcc equipped purchased new from Trainworld, and look identical to me under the shell although they're geared differently as the GP7 is much slower. They both have what look like closed end bell motors so I'll have to dig those out to see how many poles they have. There are flywheels at either end. Power is transferred via copper (?) wipers which look clean to me, but then again my eyesight isn't what it used to be.

They both have PCB's mounted on the top of the frames but I have no idea where/how power is received.

Ok don't laugh, but I'm using a Bachmann transformer that came with a Dewitt-Clinton. ( I couldn't resist!) My guess would be it is not PWM?
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Old 09-11-2019, 05:04 PM   #12
traction fan
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West DCC equipped loco running on a poor quality DC pack?

Quote:
Originally Posted by gimme30 View Post
Well GNfan you nailed it! Since the 0-6-0 has been relegated to shelf duty I decided to go ahead and take it apart and sure enough a tiny chunk of white plastic fell out when I took off the shell.
I really liked that little engine, even though it couldn't pull more than 2 or 3 cars downhill with a tailwind. I don't know that I'll repair it though...all those tiny little parts! They're cheap enough that if I decide I can't live without it I'll just buy another one.

TF I tried getting pics but my little point-and-shoot can't focus well up close. I'll try again under better lighting this weekend, or use the cell phone camera. Boy do I regret selling off all my 35mm gear now!

In the meantime I'll try to be more specific. Both engines are made by Bachmann, one is an RS3 and the other a GP7. Both are dcc equipped purchased new from Trainworld, and look identical to me under the shell although they're geared differently as the GP7 is much slower. They both have what look like closed end bell motors so I'll have to dig those out to see how many poles they have. There are flywheels at either end. Power is transferred via copper (?) wipers which look clean to me, but then again my eyesight isn't what it used to be.

They both have PCB's mounted on the top of the frames but I have no idea where/how power is received.

Ok don't laugh, but I'm using a Bachmann transformer that came with a Dewitt-Clinton. ( I couldn't resist!) My guess would be it is not PWM?
gimme30;

If the Bachmann RS3 and GP7 are DCC equipped, that explains the circuit board inside, it's likely the DCC decoder. That brings up another possibility, are theses DCC decoders of the dual-mode type, that are designed to operate on either DCC, or old fashioned DC. It also raises a couple more questions. Do you own a DCC controller? (i.e. NCE powercab, Digitrax zephyr, etc.) If you do own one, why are you using a cheap DC power pack, rather than running your DCC equipped locomotives on DCC?

I got the impression, from your first post, that you were experiencing the "lurch then stop" behavior, while running these locos with DCC. That's one thing that puzzled me, since DCC is usually very smooth running, with excellent speed control. I'm now wondering if the problem may be in that super-low-end-toy(p.o.c.) power pack from the DeWitt-Clinton set. Is that what you have been running these trains with all along, or was something else used?

The "bell" motors you saw are probably a type commonly called "can" motors, since they a fully enclosed in a metal can-shaped housing. No need to open it. If your locos have can motors and flywheels, then they are not the old three-pole motors/no flywheels/high gear ratio, duds, I was concerned about. Your locos should be capable of smooth running at slow speed.

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Old 09-12-2019, 04:45 AM   #13
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Hiya TF!

In my first post I wrote that these loco's were dcc equipped, but that I'm not. I didn't elaborate much so I see how that'd be easy to miss!
Being a gadget freak dcc greatly appeals to me and when I can move on to a HO layout that's definitely the route I'll be taking, but I don't need it, (or the additional expense!) for my little N scale track.

Anyway to clarify both engines are dual mode but you and Dennis may be on to something here. I do own a few Kato models and they don't exhibit this behavior at all, but they are DC only. Could it be that my cheapo transformer's lack of PWM is causing the problem?

Does anyone make a conventional DC transformer with PWM?

I know I need to upgrade, but I gotta tell ya, that lightweight cheap feeling Bachmann unit sure works a lot better than the metal brick I initially started with! It was one of those gold-cased MRC throttles that IIRC came with an Atlas set. All of 3 speeds....move the lever until the engine started moving, get a small increase at mid range, then no change until you were at WOT! If it ever conks out I'll use it to anchor my fishing boat.

Any advice on a suitable replacement? Current MRC models don't get the greatest reviews, and I'm not sure I'd like the knob-on-a-lever arrangement Kato uses.

Please disregard the "closed endbell" terminology...that's a throwback to my R/C days that sticks with me whenever I see a fully encased motor. When open cans were introduced we were thrilled-We could change our own brushes! True our own comms!
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Old 09-12-2019, 06:47 AM   #14
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you really should go to dcc it is much better and if your gunna move to that any way with ho ya might as well get dcc then you will have it. i use NCE witch is great , very easy to use. it has every thing you need to go right out of the box and not bad on price if you shop around a bit.
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Old 09-12-2019, 07:21 AM   #15
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Don't tempt me Sid, you're gonna drive me straight to the poorhouse!

Anyway I don't think I wired my track correctly for DCC.
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Old 09-12-2019, 10:07 PM   #16
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West DCC or DC

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Originally Posted by gimme30 View Post
Hiya TF!

In my first post I wrote that these loco's were dcc equipped, but that I'm not. I didn't elaborate much so I see how that'd be easy to miss!
Being a gadget freak dcc greatly appeals to me and when I can move on to a HO layout that's definitely the route I'll be taking, but I don't need it, (or the additional expense!) for my little N scale track.

Anyway to clarify both engines are dual mode but you and Dennis may be on to something here. I do own a few Kato models and they don't exhibit this behavior at all, but they are DC only. Could it be that my cheapo transformer's lack of PWM is causing the problem?

Does anyone make a conventional DC transformer with PWM?

I know I need to upgrade, but I gotta tell ya, that lightweight cheap feeling Bachmann unit sure works a lot better than the metal brick I initially started with! It was one of those gold-cased MRC throttles that IIRC came with an Atlas set. All of 3 speeds....move the lever until the engine started moving, get a small increase at mid range, then no change until you were at WOT! If it ever conks out I'll use it to anchor my fishing boat.

Any advice on a suitable replacement? Current MRC models don't get the greatest reviews, and I'm not sure I'd like the knob-on-a-lever arrangement Kato uses.

Please disregard the "closed endbell" terminology...that's a throwback to my R/C days that sticks with me whenever I see a fully encased motor. When open cans were introduced we were thrilled-We could change our own brushes! True our own comms!
gimme30;

I can't advise you on a DC power pack with pulse wave modulation. I think that's what PWM stands for.
However, a good quality, new, DC power pack won't be all that much cheaper than a DCC controller.
I use, and like, the NCE Powercab. It costs about $200 new retail. On sale, or used, you could probably get one for less. It has everything in one small hand-held unit. You hook it up just like a DC power pack; two wires from the controller to the track, that's it. It's easy to operate, and easy to program, and it will work with N-scale, or HO-scale. I think you will be very pleased with how slowly, and smoothly, it will run those same two locomotives; and with no lurch.

Here's an experiment you can try, before buying anything.
Test run the locomotives on battery power.
Flashlight type batteries put out pure, simple, steady, reliable DC power. If you have one of those mini 9 LED flashlights that run on three AAA cells, that will work. Pull the battery holder out of the flashlight and hook it up to a loop of track. Run one of the suspect locomotives around several times and see if there is any lurch, or other problem. If all is well with battery power, then I would be very suspicious of that Dewitt-Clinton power pack. Conversely, if the locos still behave badly on battery power, then I think those locos don't like DC power very much.
If your straight DC, Kato, units work well on both battery power, and also on the Dewhitt power pack, then your Bachmann RS-3 and GP-7 are the problem; at least when they are run on DC.
I would then suggest you try them on an NCE Powercab, or the DCC controller of your choice.

Good luck;

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Old 09-13-2019, 06:51 AM   #17
gimme30
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Batteries! Why didn't I think of that?
Chalk it up to another dumb blonde moment...

I'll give that a shot when I get home tonight!

After a quick look at what's available on the transformer market, it looks like I may have to make the leap to DCC afterall-one high end (IE more expensive) MRC unit I ran across is $150, which doesn't make sense as the Powercab will do so much more for only a few more dollars.

Better go count those pennies...
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Old 09-13-2019, 05:48 PM   #18
sid
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you wont regret the NCE power cab work fantastic and is easy to use. im a complete knuckle head and i can use it pretty good, but im stil learning . (im stuck in kindergarten) hahahaha
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Old 09-13-2019, 09:01 PM   #19
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West NCE powercab on sale

Quote:
Originally Posted by gimme30 View Post
Batteries! Why didn't I think of that?
Chalk it up to another dumb blonde moment...

I'll give that a shot when I get home tonight!

After a quick look at what's available on the transformer market, it looks like I may have to make the leap to DCC afterall-one high end (IE more expensive) MRC unit I ran across is $150, which doesn't make sense as the Powercab will do so much more for only a few more dollars.

Better go count those pennies...
gimme30;

If you can rustle up $189.36 in pennies, or other coin of the realm, www.modeltrainstuff.com is selling a brand new NCE powercab starter set for that price. I've ordered from them, and they are a good, reliable, online dealer. When you get around to building your HO dream layout, the Powercab will work fine for that too. You can also add sound decoders in future, if you want. The powercab can operate all the lights, loco sounds,(steam chuff, diesel prime mover, coupler clash, air brake sounds, and of course, the ever popular, whistles and bells your heart desires!

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Old 09-15-2019, 03:49 AM   #20
gimme30
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Ok I was able to try the battery trick with limited success. I tried 3 cells at first and one of the engines wouldn't move at all, so I tried a 9 volt, which conveniently fits across the rails but turns out is a wee bit much-that little RS3 shot off like a rocket! Both Bachmanns continued to lurch, while the Katos ran flawlessly as usual.

That rules out my cheapo transformer, so it looks like until I can pick up a Powercab this will remain a mystery.

As you know from my other thread I'm looking for more pulling power, and I went ahead and pulled the trigger on that pair of C420's I was looking at.

I'll know soon how Atlas compares!
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