Went to the layout this morning to admire a bit of work from the night before and size up the next step. Decided to give the train at crew change a run around. It's powered by three Athearn RTR SD40T-2 units. I decodered them and have them generally adjusted to run together. Powered up the controller and found I'd left them set to 22.
That's easy to do. They're broke in, but seem to have prlenty of internal friction and noisy like Athearn RTRs often are compared to some others. From a start, I often have to poke them with 90 or 100 out of 126 (on my NCE) controller to get them rolling, as I have everything slowed way down to run on the layout. As you dial in more juice, you can hear the slightly humming as you near take off speed
Down at 22 overnight, there's no humming, but they were slightly warm to the touch around the motor.
Then they usually lurch a little at around 100 and get going. You can dial back on the power once they're rolling and as they warm up, the lurch is less pronounced and at lower speeds, but not too much difference, just enough to be notable.
Anyway, thinking abouit this - because I've been considering going in and trying to improve the lurch with some CV massage lately -- I thought, "Wonder what speed they will start at now after being kept idling all night?"
They took off nice and slow at 60 (maybe a little slower actually, but I was hitting the Up 10 speed button)! I mean really smooth, no lurch. A considerable improvement. I was impressed and think messing with those units isn't what's needed. I know people tune these things, but maybe we should just let them "idle" for an hour or so before we start them?
Mike Lehman
Urbana, IL
What brand of decoders are you using? With NCE D13SR decoders I have always been able to get my old Athearn locomotives to creep on speed step one by adjusting CVs 2, 116, and 117.
I buy NCE decoders in bulk packs of 10 specifically for use in Athearns, even some so old that they have no flywheels.
They're all NCE decoders. Yeah, I'm sure I can improve on what I have programmed. But that's just the "software" (really firmware) side of things. It seems that the hardware could gain from some massaging, which I'm also aware of.
What was surprising to me is that the difference I experienced has to all be in the motor itself. The gear train wasn't warmed, at least in comparison to the motor, so I suspect none of the improvement came from that, which many of the folks who do tuneups obsess about. Beside, on the Tinnel Motors, half of it sits in a very well ventlated "screen porch."
One thing this brought to mind is using different lubricants. The Shay Fixer has been selling Nano-oil for some time and friends rave about its dramatic reduction in friction without anything else being done to the drive than being cleaned up and relubed with it.
Guess I'm bringing this up because I always assumed the attention to the gear train seemed really important. And folks wanting to sell you a new Gee-Whiz motor want you to think you need one of those. But If I can get most of that gain much more simplyu, I'll settle for that approach and save a lot of time and money.
mlehmanI know people tune these things, but maybe we should just let them "idle" for an hour or so before we start them?
By "idling" are you suggesting that power should be applied to a motor at a level just below the point where the loco will move, and then letting it sit there for a period of time to "warm up"? Doesn't sound like a great plan to me.
mlehmanOne thing this brought to mind is using different lubricants. The Shay Fixer has been selling Nano-oil for some time and friends rave about its dramatic reduction in friction without anything else being done to the drive than being cleaned up and relubed with it.
I'm another Nano-oil advocate, use it on all of my shays. climax, heislers, Bachmann 44 ton, Proto 0-8-0. its amazing stuff and well worth it. One tube is a lifetime supply.
"The true sign of intelligence is not knowledge but imagination."-Albert Einstein
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I only let my engines idle when It's below zero out...but I kick up the rpm's so the turbo don't load up.
Take Care!
Frank
maxmanBy "idling" are you suggesting that power should be applied to a motor at a level just below the point where the loco will move, and then letting it sit there for a period of time to "warm up"? Doesn't sound like a great plan to me.
Well, sorta. At step 22, it was actually way below what it takes to get that consist rolling cold, which is about 100/128 on my NCE PowerPro controller.
I'm not saying I'd necessarily recommend this. Coreless motors hate this sort of stuff and could be damaged. Don't think there's anything that fancy under the hood on these Athearn's, but willing to entertain enlightenment that this could hurt them, part of the reason I posted about this. I doubt there's any problem with doing this with the DCC system itself.
The main reason I'm considering it is the nature of this consist's current assignment. It powers the longest/heaviest train on the line, so has to sit in its own special long hidden siding. It's dead cold to start with, comes out of staging, immediately stops to pick up a helper, then the slow climb to the summit just before Durango. The issue is that the balky nature of this consist makes train handling a little dicey, which is not good when there's a 4-unit helper pushing.
If it was all warmed up and performed like this morning from the get-go, it would be great. That's why I'm thinking I may start setting it "at idle" an hour or so before an ops session starts. Still planning on fiddling with the CVs, but this obserevation seemed interesting enough to report and dicuss.
Mike,After my SCR "crew" signs in the engineer proceeds to start S4 112(A Bachmann DCC/Sound S4) and let it idle while the conductor checks the day's switch list.
So,I see no harm being done by letting the S4 idle for a short period of time.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
Larry,
Yeah, but I think you're talking about letting the decoder make sound, not feeding power to move the unit, maybe?
These are non-sound units (well, they're Athearn's, you know "non-sound" is relative ), except for the hum coming from the motors as they complain there's not enough juice yet to get moving.
mlehman These are non-sound units (well, they're Athearn's, you know "non-sound" is relative, except for the hum coming from the motors as they complain there's not enough juice yet to get moving.
These are non-sound units (well, they're Athearn's, you know "non-sound" is relative, except for the hum coming from the motors as they complain there's not enough juice yet to get moving.
cacole,
Had a few minutes over lunch to grab these units and check what was in them on the programming track. I thought at first I must have messed these up when I went through all my SG diesels a few months ago to slow them down.However, my operators sometimes start punching the extra buttons on one of the NCE hammerheads that are available, so that could also account for this as they were running these a couple of weeks ago.
All had CV 2 at 10 and I left that alone for now. CV116 and 117 were all over the place from 0 on up. I set CV 116 at 2 and CV 117 at 30. This helped low speed performance a bunch, lot less lurch to start out, although they're still a little cranky. Thanks for pointing me specifically at them, saved some time going through each one to see what was the common fault. I did quiet the hum before start-up a lot. Any feedback on the current settings would be appreciated.
The newer RTRs aren't that much different in performance from the old BB units. I used to tweak my BB locos and they actually would run quite well. You would think that after many hours of "break-in" and use that they would perform consistantly. I would find that if let sit for any extended period, a new run in, work out the "cobwebs" each time until the performance returned, Go figure?
Modeling B&O- Chessie Bob K. www.ssmrc.org
The documentation that comes with the NCE D13SR decoders says that CV116 typical adjustment is 2 to 4 -- I normally start off with a value of 3.
Normal range for CV117 is 4 to 25. I start at 8 and work upward until the unit will creep at speed step 1. You may need to lower the value in CV2 as you adjust CV117.
Adjustment of CVs 116 and 117 should take the buzz out of the Athearn motors.
mlehman Larry, Yeah, but I think you're talking about letting the decoder make sound, not feeding power to move the unit, maybe? These are non-sound units (well, they're Athearn's, you know "non-sound" is relative ), except for the hum coming from the motors as they complain there's not enough juice yet to get moving.
Well,apparently Athearn uses different motors in their RTR engines..As a example my two SW1500s and both GP60M is as quiet as a Atlas.I have 2 RTR GP40-2 and 1 GP38-2 that is just as quiet.
The others has the normal motor hum even though they have the newer drive train..
cacoleThe documentation that comes with the NCE D13SR decoders says that CV116 typical adjustment is 2 to 4 -- I normally start off with a value of 3.
Yeah, the documentation has some small differences with my PowerCab and PowerPro manuals. They say...
Theb typical value is 2-4 with a maximum practical value of about six. The smaller the number, the more often the motor gets a brief voltage kick. A value of 0 turns off the kick. A value of 1 gives continuous kicks to the motor (not very useful). When using Torque Compensation (CV 116) set the Start Voltage (CV2) to 0.
I've tended to use 2 as a default value, figuring a lot of kicks is better than fewer kicks, which I think would be 6, but the language reads a little rough, since it says that's a "maximum value"?
For CV 117 it says:
This is how hard the motor is kicked at low speed. Typical values range from 1 to 40. High quality motors (Kato) need very little klick strength where lower q2uality motors such as old Athearn and lifelike need relatively large values (30-50) for slow speed crawling.
What I found was that I had one unit that was just a smooth, quick off the mark unit. I tried played with CV5 and CV6, but didn'tr get enough improvement before other units started getting out of sync. I finally turned CV116 to 4 and turned CV117 way down to just 8. Then they started really playing well together. Much better, smoother, wide control range, a joy to run. Thanks.
BRAKIEWell,apparently Athearn uses different motors in their RTR engines..As a example my two SW1500s and both GP60M is as quiet as a Atlas.I have 2 RTR GP40-2 and 1 GP38-2 that is just as quiet. The others has the normal motor hum even though they have the newer drive train..
You gets bugged by loose stirrups. It's the highly variable motor/drivetrain performance that bugs me about Athearn. It is getting better in general, though. I've not heard so many complaints about that in recent years.
These units were from the very first run of Tunnel Motors. I'd say they're broken-in, but still needing some tuning. I've been getting back to a number of units with little issues after going through and slowing them down to match suggested track speed and the slow clock.
mlehmanYou gets bugged by loose stirrups. It's the highly variable motor/drivetrain performance that bugs me about Athearn. It is getting better in general, though. I've not heard so many complaints about that in recent years.
Athearn does seem to be improving their drives..I love the slow switching speeds of my two SW1500s.The GP60s has seen several hours of run time at the club during open houses and no complaints there.My GATX GP38-2 is another slow switcher.
As the above engines show Athearn does have the know how to get the job done.
mlehman Went to the layout this morning to admire a bit of work from the night before and size up the next step. Decided to give the train at crew change a run around. It's powered by three Athearn RTR SD40T-2 units. I decodered them and have them generally adjusted to run together. Powered up the controller and found I'd left them set to 22. That's easy to do. They're broke in, but seem to have prlenty of internal friction and noisy like Athearn RTRs often are compared to some others. From a start, I often have to poke them with 90 or 100 out of 126 (on my NCE) controller to get them rolling, as I have everything slowed way down to run on the layout. As you dial in more juice, you can hear the slightly humming as you near take off speed Down at 22 overnight, there's no humming, but they were slightly warm to the touch around the motor. Then they usually lurch a little at around 100 and get going. You can dial back on the power once they're rolling and as they warm up, the lurch is less pronounced and at lower speeds, but not too much difference, just enough to be notable. Anyway, thinking abouit this - because I've been considering going in and trying to improve the lurch with some CV massage lately -- I thought, "Wonder what speed they will start at now after being kept idling all night?"
Joe Fuegate commented back in his old forums about Athearn RTR drives like those in the SD40T-2's being a little stiff. He suggested using decoders with the backEMF feature, and said his experience was that it improved the performance of those Athearn drives, making them start and run more smoothly. I'm a noob, but I've picked up a few TCS1 and TCS4 decoders to install based on his recommendation. I'm still working on the layout so I haven't gotten very far with the DCC system stuff and just picked up a Digitrax DT402D throttle to make my old Radio Chief system a little easier to use. But the BACKEMF thing was worth mentioning if others are having the same issue you were, taking a higher number to get them started.
Rio Grande. The Action Road - Focus 1977-1983
Jim,
Thanks, sounds like good info. The D13xx group of NCE decoders don't have a back EMF feature, so would have to upgrade.They're way, way better than they were, so not feeling the need to.
The long term plan is to install sound in all 3 units, so I won't make any changes before then in hardware. Just hasn't been ahead of other budget priorities, which I'm sure you know what I mean. Pretty much all the sound decoders now feature back EMF. Most likely they'll get Tsunamis, but I'm prepared to be WOW-ed if they release the diesel version before I get around to converting them.
The back EMF with LokSound Select decoders is smoother than a Tsunami, and I think their sounds are better, too. And they are cheaper.
I am technically a DCC noob, but I've been told you have to dial back the Back EMF when you run those diesels with others in MU form or they will fight against each other.
That's what I've heard about basic ol' BEMF. I believe some high-end decoders now have built-in compensation for BEMF when in consist, but don't keep up with the latest and greatest that closely.