Is the new Arnold U25C the best N scale engine ever?

[bbussey]

The little "nubs" in a MT coupler don't really center it, do they.  The spring does that.

Instead, I always thought they:
1. reduced compression.
2.  Provide a swing terminus (limiter).

They keep the coupler from drifting off-center. Otherwise, the coupler lists to the far left or far right. The spring by itself does not keep the coupler centered.

[bbussey]

I'm not sure what you mean by centering nubs. Can you show me a picture of an MTL that illustrates what you're talking about?

Thanks,
-Mark

I will send you a photo when I return home later.

[peteski]

Those nubs (along with the elongated slots in the coupler box) in the MT coupler are also what allows it to open during uncoupling (when it swings to the left when the force is applied to the coupler half with the trip pin) and yet keep it closed when the entire coupler swings in either direction. The split-shank is a quite ingenious patented system.

[Spikre]

 
    Edit:
   the CR units made it into the 80s,retired by 1983,most
   or all traded back to GE on current models.
    did see some PC/CRs on the Erie mainline thru Waldwick
   during 76/77.
    almost as odd as seeing the PRR/PC/CR GP9Bs in the area.
        Spikre
         

[Hornwrecker]

MBK just got another six, of each road number, in today.

[spookshow]

OK, important safety tip - do not accidentally dislodge one of those flimsy little cut-lever detail pieces. In all the universe there aren't tweezers fine enough, eyes sharp enough, nor hands steady enough to get that bleeping thing plugged back in!  Grrrr

Cheers,
-Mark

[spookshow]

And since I'm already mangling things, here ya go -



Cheers,
-Mark

[peteski]

LOL Mark!  Send it to me - I'll fix it for you.   

The coupler shank looks to be an exact clone of MT coupler design.  But Bryan wanted to see the other side of each shank (looking for little nubs poking out of the outside surface on the loop). 

Here is an original and genuine real  MT coupler showing the features Bryan was looking for.


The nub is visible near the spring and the coupler box cover has a depression visible by the mounting screw hole.  Is the Arnold coupler similar to that?

EDIT: what else ... speelling 

[spookshow]

The nub is visible near the spring and the coupler box cover has a depression visible by the mounting screw hole.  Is the Arnold coupler similar to that?

Ah, I get it now. Yes, they are exactly like that.

Cheers,
-Mark

[Mark5]

So, does this mean that they "slink"? 

[peteski]

So, does this mean that they "slink"? 

Most likely. But less than the couplers where the spring is behind the post (like the 1023/25s and the truck-mounted ones on MT trucks).

[JSL]

They are back in stock at MBK. One NP is already at 0 in stock.

[Nato]

          I just received two Burlington locomotives. First the Gray Color, it looks too light to me color photos of the prototype look darker, but not as dark as some Atlas or the LL GP20. I love the road specific details, lights, horns, antenna's etc. The MU detail on the pilots is very nice. Even the small model ID plate, markings "U25" found on Burlington locomotives is there. Out of the box my first locomotive ran smoothly and quietly. My second locomotive when placed on the rails just sat there with it's headlight on made no noise and acted the same way in reverse. By lightly pushing down on the entire locomotive I could get it to move forward, but not reverse keeping it pressed down to the rails. After going forward just a bit I stopped pressing down and it ran by itself. After a short break-in forward run, when switched to reverse it tried to move, pushing down made it move, after a short time removing my hand it also ran by itself in reverse. After a bit more run time it now runs just like the first one.                                              Spookshow and others thanks for the useful disassembly and mechanism photos. Nate Goodman (Nato).

[u18b]

So who will be the first to do something new with this new loco?

New possibilities have been opened up.

Remember, early U28Cs arrived in U25 carbodies....

Like this one I kitbashed and painted for SCL.

[nkalanaga]

Ron:  An NP, CB&Q,or BN U28C would hardly qualify as a "project" - just change the numbers.  The last few NP U28Cs actually produced 3,000 HP, so were technically U30Cs, though never listed as such.  And they still had U25C bodies.

Got my Hornby U25Cs today.  They're beautiful locomotives, but...

Took the first one, NP 2525, out of the box.  Left side handrails loose, as other have noted, but everything else was in place.  Checked the gauge, as that's critical for my dual gauge turnouts.  All six axles were badly out of gauge, up to 1/32 inch narrow.  A small flat screwdriver easily pried the wheels out to match the NMRA gauge.  So far, so good, nothing that hasn't happened on other locos.  The trucks seemed a little "floppy", but that may be normal.

Put it on the track, ME code 55 on an 18 inch radius curve, the easiest part to reach.  Ran about five feet and stopped.  Pushing it didn't help, no lights on.  Removed from track, and tested with leads from the power pack.  The only axles picking up power were the two middle axles, the ones with the traction tires.  Took sideframes off, wipers not touching the wheels, probably because I widened the gauge.

Adjusting the wipers took a while, because the only way to bend them is to remove the wheels, at which point the wipers fall off, and there's nothing to hold them on until the wheels are back on.  On the other hand, taking the trucks apart is easy, and one doesn't have to remove the sideframes, although it's easier.  The sideframes hold the wipers on, which is why they fell off when I took the truck apart.

Put everything back together, and the loco ran - except through one tunnel.  Straight, flat track, and my MiniTrix FM, with its primitive electrical system, went through fine.  Finally got the new unit to go through, after MUing it with the FM, and pushing/pulling it back and forth a few times.  Being pushed, the rear axle of the front truck would lift, due to the way the trucks are mounted, causing derailments on curves.  This unit needs to be behind any faster units.  I also tried running it with a Kato SD40, and it didn't like that at all, nor did the Kato.  The speed difference is too great.  So much for running an all-NP U25C/U33C/SD45 lashup.

Earlier there were thoughts that it might have wires for pickup.  I think that would be an improvement.  The current system goes wheel - truck wiper - vertical wiper - horizontal PC board wiper. A wire from the truck wiper to the PC board would almost have to be more reliable than all of those contact points.

The other NP was closer to gauge, and didn't need the wipers adjusted, but ran about the same.  They run smoothly when they run, and seem to have good pulling power.  The slow speed is a personal issue, and others may very well consider it an advantage.  DCC users won't notice it at all.  But the contact and axle lift problems could have been caught in testing, if not in the design phase.
**********
On the last lap, there was a loud POP from the MRC handheld throttle I use, and everything stopped.  Now I need a new throttle.  I can't imagine it's related to the Hornby unit, as I've short-circuited the throttle numerous times, with no damage, and the locos were running fine when it died.

In the middle of working on this new "Arnold" model, I hauled out my really ancient Arnold/Rapido "FA-whatever".  I had one in the late 60s, as my first true N scale loco, but this one was found in a house by someone about 15 years ago, and given to my "local" hobby shop to be sold on consignment.  This is a complete set, except for the cardboard box.  The vacuum-formed plastic liner, and clear plastic cover, loco, two freight cars, caboose, track, and power pack, all original late 60s or early 70s.  The power pack is even labeled "Made in USA"!  I keep it wrapped up, on the bottom shelf in my closet, under everything else, as I have no intention of using it regularly, but thought the comparison might be interesting.

The wheels on the FA were all in gauge, although the flanges are too deep.  On ME code 55 they hit the spikes, and might hit the ties.  But all of the wheels were clean and shiny, so I gave it power, and it took right off.  Ran smoothly, and even with the flange problem, didn't wobble or hesitate.  It even ran through my dual gauge track without shorting, and never showed any sign of poor contact.  Turn the flanges down and I wouldn't hesitate to use it.  Almost fifty years difference in the two Arnold models, and I can't say that the new one is better, mechanically or electrically, although it's much prettier.  The FA went back in the box, and the U25Cs will probably be scenery.  I would hesitate to buy another Hornby model.  Hopefully others will have better luck.

And that MRC "Cab Control 55"?  I took it apart and couldn't find any obvious problems.  Nothing is scorched, power goes in, no power comes out, nothing smells burned.  Fortunately I bought two, many years ago, so I dug out the spare.  The instructions say it has an electronic cicuit breaker, which should reset automatically, but that shouldn't make noises even if it fails.  On the other hand, the noise could have been a coincidence, not unusual in our house, especially with the heat on, as the ductwork often makes noises.  But it didn't sound quite like that, or like a cat getting into something.  Maybe it just died of old age.