Kato RS11

[peteski]

Thanks Max. I believe you. But it looks like if I want some exact info I would have to dig out some of the older Katos out of my stash and start counting gears (and evaluate the motors).  Maybe someday... 

[brokemoto]

Which specific run of F3s are you talking about?  IIRC, the initial run used truck construction similar to the trucks discussed in this thread (and maybe the Kato GP38-2 trucks). 

The truck construction was, in fact similar to that of the Atlas/Kato RS/GP chassis under discussion here.  The electrical contact was the same.  The gearing, as mmagliaro has demonstrated, was, in fact different.  The lower gearing and the presence of flywheels made two important contributions to the F-3's better performance.  First, it allowed a better use of the motor's speed ranges, as mmagliaro had indicated.  Second, presence of the flywheels allowed the thing to coast until electrical contact could be re-established.  To be sure, the initial runs of the Kato F did stall more than did the later runs.  This was due to the electrical contact being similar to that of the chassis under discussion.  Kato revamped both the cab unit chassis and RS-configured chassis.  The result was improvement on the already pretty good performance of the former.  Kato also re-geared the trucks on the latter.  The improvements first appeared in the Atlas/Kato SD-7/SD-9, which is to this day one of the best operating N scale locomotives out there.  I am guessing that it has been out of production for at least fiften years, but few subsequently issued RS-configured units have equalled its performance.

I will disclose, here, that I have not bought the Atlas SD unit of Chinese manufacture, so I do not know if it equals or surpasses the performance of the Atlas/Kato SD unit.

[peteski]

Thanks Brokemoto!

[mmagliaro]

This chart may help.  I don't have ever single gear Kato's ever made in there, but I have most of them:

http://www.maxcowonline.com/maxspage/projectFiles.php?projectStringData=picdir%3Dgears%26picidx%3D29%26lastpic%3D0%26lastpic2%3D0%26picstyle%3D9%26

[sirenwerks]

Two questions...

I am I correct in presuming the new Atlas RS11, the one with the proper wheelbase, is geared and motored in a manner that gives it the slow speed operation and torque Max finds favorable?  I still need another pair in NP paint.

And a return to a previous line of query... What options are there for using a third party motor?  Are there motors suitable out there that I can get without sacrificing another loco to, in essence, pop in the existing frame? If so, what manufacturer and model number and where can I buy it?

Bryan

[mmagliaro]

I can't comment on the new RS11.  If somebody has one and can clock it at full throttle (and that means not cheating
with speed steps, but clocking it when the motor is actually getting about 12 volts), I can compare that top speed
to my old F3's.

If you aren't going to cannibalize another chassis to put under your RS11 and you want a new motor, a Mashima 1015
ought to fit in there without too much trouble.  It has nice long dual drive shafts of the correct diameter, and the motor body
is small enough to fit into the old RS-11 without any major surgery, although you may have to shim it to get it to stay
put in the correct position.  Mashimas generally turn slower and with more power than the stock motors.

You can get it from micro-loco-motion.com (you will have to email him; there is no online ordering),

or here:
http://www.gizmoszone.com/shopping/agora.cgi?product=DC_Motor;ppinc=1g  as part MHK-1015
(Hong Kong)

or here:
http://www.hollywoodfoundry.com/   
(Australia)

It's frustrating to me that these are not as easy to buy from a US shop as they ought to be, but there it is.


Another possibility is the Atlas "scale speed" motor - but I don't own any of those so I don't know if it would fit without
frame grinding.

[peteski]

I think that the speed problems mentioned here are greatly exaggerated.  From the early years to the present Kato locos were and are speed demons.

So what if RS11 has a top speed (at 12V) of 300 Smiles/hr while the "slower" Kato locos might top out at 200 Smiles/hr?  I understand what Max says is the problem but seriously, how many of those locos were sold and how many people kept on happily using them? Lots!  How many people actually re-geared or re-motored them to slow them down?  Maybe 0.1%?  I wouldn't worry about their slow speed performance.

[strummer]

What I'm finding interesting about this thread is that we're talking about a model that's been around since the mid-80s(?) and its generated enough interest to warrant 3 pages (so far)...

I must not the the only one who has had these items...for better or worse

Mark in Oregon

[Wardie]

My first two N scale locomotives were Atlas/Kato RS-11s, both Maine Central units. At the time they were better then any of the HO stuff I had as a kid, and I put the Micro-Trains pilot conversions on both of them and they ran quit a few miles on first small layouts. They have however been  replaced by the newer Chinese made versions. The DCC mechanisms along with the body upgrades sold me on the newer ones, and of course Atlas did both Maine Central schemes on them so I have 6 models of 2 RS-11s. I am not planning to get rid of the two Kato's though, they run ok and we're my first N scale locomotives. But if I was modeling RS 10s and RS-18s I would start with the Chinese models.

[peteski]

Yes, these were some of the best (or the bast) running N scale models i9n the 80s.  Also the current versions are superior to those 30 year old models. No question about it. But some of the posts here make the original models sound like they are really terrible runners.  They're not that bad.

[strummer]

I think probably half of my diesels are 80's Kato built Atlas, and I like 'em all. True, they may not be quite as smooth or quiet as the Chinese-built Atlas models,but they weigh a little more, so they pull as well if not better,and I admit I rather enjoy doing the coupler conversions.

Mark in Oregon

[mmagliaro]

Let's put some hard numbers on this.

I just clocked the F3 at full speed.   72.7 mph
The newer F7  167.8 mph

Look, the F7 is no piece of crap.  It's a great engine.  But it would be ever better if it were geared down.

I don't have a stock RS11 anymore, but I think that it is even faster than these F7's.  Everything runs better
when it's geared down, so why not just build it that way?

(I think I'm more sensitive to this issue than most because I mostly build steam, and the improvement
in a steam loco is really dramatic when you gear it down).

[wcfn100]

Let's put some hard numbers on this.

I just clocked the F3 at full speed.   72.7 mph
The newer F7  167.8 mph

How much of that do you think is the original non low friction trucks?

I have a bunch of the original drives (blue boxes) and I'm not sure where they stand as far as getting used now vs. the newer DCC drives.

Jason

[peteski]

Let's put some hard numbers on this.

I just clocked the F3 at full speed.   72.7 mph
The newer F7  167.8 mph

Look, the F7 is no piece of crap.  It's a great engine.  But it would be ever better if it were geared down.

I'm not disputing the facts. But most modelers don't really care if the top speed is 80, 160 or 300 Smiles/hr.  Yes, I know that high gearing  results in poor low speed torque.  But with DCC and BEMF this problem is not that bad.  It is amazing how much low speed torque can be achieved  by a decoder with PWM motor drive (which is how all DCC decoders work).  To me taking care of the reliable pickup in those older locos would be more important than reducing the top speed.