Just picked up an PSC M2 (#1147; I plan to renumber it as 1129 and put a 15Kgal tender on it). The detail is phenomenal, but I’m a little disappointed with the performance. I have two 2% grades on my layout, and it REALLY slows down going uphill and speeds up going downhill. I have lubed and greased it, but no help. Wonder if repowering it with a nice can motor would even it out some. I do note that my power pack has a “flat spot” in the output (essentially the same output voltage for about 15% of the dial rotation) and that is the voltage it wants to run at for the speed to look right.
Anybody else have this experience with the PSC M2s, or am I on my own here?
My experience with PSC is that the motors are generally underpowered for the size loco they are placed in. Providing that there is not a bind in the mechanism causing this, if the loco slows way down with a moderate load going uphill, and doesn’t reach a point where the drivers slip, you can assume that its getting close to the stall current. Staying near the stall current for long periods of time, will burn the motor out sooner rather than later. Depending on the motor, this can be as little as 2-3 seconds. You can’t go wrong with replacing it with a good quality, adequately sized, can motor.
Got any suggestions? I think I’m looking for a small, high-torque, low RPM motor. I generally don’t run over 40 Scale MPH as it doesn’t “look right” for my layout.
I have the M2c as well. Mine is #1157 with the 9k gallon tender. I called PSC technical support before I bought a decoder for mine to ask if they had a suggestion for the decoder. In speaking with them I was told that the engine is not a good puller, which I interpret to mean that it is underpowered. I changed out the spring that was under the pilot truck to improve tracking performance and it began to run better, but I have not tested it on any other grades. I did measure the stall current on mine and it 0.49 amps. I am interested to see how it will perform after I install the decoder that I bought for it.
The Tech 4 220 is only 16VA (1.3 amp output @ 12 volts) and if loaded down with accesories, or multiple engine’s, will not reach 12 volt’s. I had a top-of-the-line MRC, when lighting my ‘accessories’ roundhouse it dropped my track voltage to 3.5 volts. (It had meter’s).
Don’t count on it. That’s @ 0.26 amps per engine and NO cars.
I would check the weight factor (drag) of car’s being pulled.
That alone has an affect on uphill/downhill performance. A bigger motor pulls more amps. and does more work, but also has to ‘fit’ - no small undertaking.
Does the engine (by itself) measurably slow down going uphill?. 2. If so, have you talked with PSCabout it? 3. How many car’s are you trying to pull?
Track: oval on 4x8. All turns to left. 1 180-degree turn with 2% uphill grade, 1 180-degree turn with 2% downhill grade, 4-foot straights in between.
Test data is for loco and tender, no cars.
At 8.5 volts, loco runs approx 25 scale MPH on level straights. Loco takes 16 seconds to complete the climbing turn, drawing .18 to .19 Amps, and seems to be close to stalling out. Loco completes downhill turn in 11 seconds and draws .14-.16 Amps. Loco draws .15-.16 Amps on level straights.
At 12 volts, loco runs approximately 45 scale MPH on level straights, drawing .16-.17 Amps. Uphill turn takes 6 seconds and draws .2 Amps. Downhill turn takes 5.5 seconds and draws .15-.17 Amps.
I would ideally like to run the loco at 20-35 scale MPH.
Got your numbers. Good job. I suspect you have a ‘Can’ motor with those low amperage figures.
Seems you want a bigger motor with more torque that FIT’s - and possible regearing.
If it were mine, I’d call PSC. There was a guy there that moved from Denver - I think ‘Larry’ was his name - and he used to do remotoring and brass work for Caboose Hobbies. He would be in engineering, and I’d try to get his opinion.
He re-motored and re-geared two of my Balboa’s for me. He’s also pretty sharp.
Me thinks you are talking about an N&W Class M 4-8-0 Mastodon. Excellent looking engine that I have (as yet) managed to fight off the tremendous urge to purchase. I don’t see where you have a problem. Unless the wheels stop turning you are not underpowered. (Note, power is not tractive effort because they may slip.) All I run is straight DC, and all my brass engines with good can motors are much more sensitive to grade than anything else I run. Your amp draw isn’t changing much either. Top speed is a little low, but you said you didn’t even want to go that fast.
On the old Canon motors (which were very good) you could adjust the speed / torque by changing the brush position relative to the stator, and you may well have that situation, if I were you i would definitely check it out. But, if you get more speed you are probably going to have less torque at an equal amperage, and I don’t think you will get less slowdown on uphills and you may get more. The “solution” may be to go to a lower quality motor that draws more amps and is less sensitive. Or, go DCC with a back EMF control logic.
P.S. - Real locomotives slow down on grades too, and 2% for them is considered a whopper.
We be talking about an N&W class M2 Mastadon - the “biggie size” M:
Yeah, I realize that 2% is a pretty steep grade. I may see how much I can cut it back - don’t have room for 1% without a MAJOR rebuild, but might be able to get around 1.5%.
I put a slightly stronger spring on the pilot truck in mine. I was having problems with it going around an 18" radius flat curve on my test track because the pilot wheels kept coming off the track. The strange thing that I noticed is once the pilot wheels came off the track, it seemed that the rear driver wheels would lose electrical connection like it was too heavy in the front, and it would start sputtering around the track. when I put the slightly stronger spring on, I had no problems with the truck derailing and it ran consistently better around my level test track. I don’t know how it will handle the grades on my layout yet. My project this weekend is to install the decoder that I bought for it. I bought one with back EMF so hopefully it will run ok on my grades.
What are you going to do with the tender that you have on yours now? I have the small 9k gallon tender, but wanted the one that you had.
I have a Westside 15 Kgal/20T tender I plan to put behind it; I also plan to put a Pyle headlight on it and renumber it as #1129. That configures it as a '55 - '56 model; I model N&W 1955-1960.
