DCS steam slow speed dcs vs legacy

Most of my PS2 and PS3 steam run smooth at 1 SMPH and all of these steamers run smooth at 2 SMPH. My PS2/PS3 diesels and electrics all run smooth at 2 SMPH except for one particular electric that doesn't run smooth until 5 SMPH.

Regardless, MTH has at various times advertised that DCS engines run smooth at 2, 3 or 5 SMPH. I expect newer PS3's should be the best at slow speeds.

Also, Legacy speed step 1 is not 1 SMPH and Legacy speed step increments are not the same for all Legacy engines. If I recall correctly, Legacy "switchers" (however, they're defined) have slower speed step increments, at least on the low end, than do other Legacy engines.

Perhaps someone who is more knowledgeable than I of Legacy can shed more light on this subject.

My Legacy Heavy Mikado and VisionLine Big Boy both move at the same speed when set at the same speed step.  I think I did the math one point and when set at speed step 48 they were going about 25 MPH.  My Legacy B6sb moves even slower, about 2/3 the speed as the other two.  But if they are put together in a train, the switcher is set to road speeds (The remote will even warn you about this.), but doing so will add a speed limit to the train as the switcher can not go as fast as the road engines.

I don't own any PS2/3 locomotives myself, but a friend does, and yes, all his are jerky at slow speeds and don't even out until 3-5.

My MTH steamers run fine at slow speeds???

Gentlemen,

   All my DCS & Legacy remote control engines, especially my Tin Plate, run great at slow speeds, it's like a little boys dream come true for me, and I actually lived to see the technology on the tracks, just as my Grandfather told me I would.

PCRR/Dave

I have quite a few PS3 engines that run very well at around 2 smph. I have not verified the speeds of every engine I have, but I haven't noticed any of them that are jerky when going slow. These are all diesels, I don't have any steamers.

Joe,

The Hudsons look great!

Just curious  - why are the smoke units behaving differently? One's smoke dissipates quickly while the other's hangs in space much longer.

I have quite a few Legacy locomotives and I have never seen any locomotive run more slowly than a Legacy loco does regardless of what the smph is. I have five or six DCS locomotives and all run as slowly as the Legacy locos do, but not as smoothly in their first two speed steps. They all smooth out at speed step or 3 smph whatever it is called. That third step does not seem to be as slow but, it really is splitting hairs. If you like what you have, that is all that counts. I love the MTH locos I have. They do things no other locomotive does from any other manufacturer including Lionel. Eye of the beholder kind of thing. I opened two new Lionel locos tonight and they crawled along beautifully right out of the box.

The two Legacy switchers I have, the Genset and the B6sb, are the low speed champs for me.  The other Legacy stuff, is very good as well, but they do start out a bit faster than the switchers.  My DCS stuff smooths out around 3 scale MPH, pretty much what MTH claims.  I do have a couple that will actually run smooth at 1 scale MPH, but that's the exception.  All of the above locomotives and brands have excellent performance, no complaints.  If you're splitting hairs, the Legacy locomotives probably have a slim edge in the low speed performance, but not enough to be significant.

All the poster does is bash MTH.  I am sure I am not the only person to pick up on this.  I question if he actually has the locomotives he talks about.  I have requested pictures in the past and they do not get posted.   He went at this subject not long ago.  Show us a video.   I am a Legacy fan and recently sold my 844.  The 844 was early Legacy with modular boards and not the great RCMC system we enjoy today.  On it's best day it would not move smooth at step 1.

ironlake2 posted:

 my dcs proto 3 premier sp daylight at speed steep 1 runs very slow but super jerky 

There is something wrong with your engine.  Other PS3 steamers don't do this.  Take it in for service at your LHS.

My ps2 gn r1 and ps2 gn s2 also jerk at smph 1@2 but in talking to mth they claim this is normal.  Also my mth sd 70 ace does not start to run until speed step 5 but is smooth and is considered normal by mth.  My legacy sd70 ace just creeps a speed step 1 and all my lionel legacy engines run slower when side by side with dcs on the slowest setting the mth engines run faster at that speed step.  I am not bashing mth , I am just telling the truth.  I thought this problem would be gone with proto 3 but not so.

I have no Legacy but I do have a MTH sd70ace rail king and a 2-8-0 rail king, both PS3. The sd70 when new was jerky at 1 smph but smoothed out at 2. After some  weeks of use it  doesn't smooth out till 3 smph. The 2-8-0 was slightly used when I got it and it was really jerky at 1 smph, less so at 2 and smoothed out at 3. Pulling a few of my heavier cars, they both seem to smooth out sooner. The sd70ace at 2 smph and the 2-8-0 is less jerky a 2smph. I suspect the weight of the cars are helping take some of the backlash out of the drive train. Maybe some of the experts could tell me if my backlash theory could be correct.

I would be curious to see side by side comparisons.  I can see 2 or 3 SMPH being a natural 'smooth' point from the technical end, but it seems the Legacy engines can move along a bit slower.  I don't have either to compare with, but if someone was so inclined, it isn't very hard to determine speeds.  In my tests of the LionChief engines I used a length of straight track exactly 66 inches long(1/20 scale mile) and a stop watch to see how long the engine took to move that distance.  Some simple math yielded the speed in Scale miles per hour for each step.  ( ( 1 / ( time * 20 ) ) * 3600 ) = SMPHFor really slow speeds it may be quicker, if a bit less accurate to use a 33 inch track and multiply by 40, or 16.5 inches multiplied by 80.  I like the longer track because it averaged out my hand-eye coordination better.  Also useful to have a straight section of at least the length of the engine before the timing area so as to exclude the possibility of slowing around curves.  

When it comes to the two systems, they seem to operate in rather different ways, and I've yet to find a satisfactory reason that MTH's engines can be as far off from their reported speed as they often seem to be, with the equipment they use to report speed to the processor.  I'm curious if Legacy engines behave the same as LionChief engines with their speed steps, where a given step is a set speed regardless of load or voltage.  For example, if step 20 is 5 SMPH at 18VAC with no load behind the engine, is it still 5 SMPH at say 14VAC, or with 20 cars behind it?  

Anyway, if anyone wants to duplicate my test of LionChief Plus speed control with various Legacy and DCS engines I would be very interested in the results.  

JGL

I don't have 66 feet of a straight to do the test!

"For example, if step 20 is 5 SMPH at 18VAC with no load behind the engine, is it still 5 SMPH at say 14VAC, or with 20 cars behind it?"

I tested the first Legacy locomotive (Big Boy) with 9 VAC on the track and with 16 VAC on the track.  The speed steps were identical up to the point where the 9VAC test reached its max speed.  Of course, more speed was possible with 16 than with only 9 volts.

It's a legitimate question.  In my experience a Legacy loco will be smoother.  After years of dealing with complaints about the Odyssey "lurch," etc., when Legacy debuted, Lionel made two important changes:

(1) More speed steps (256 in all)  There are probably 5 or 6 speed steps between zero and 3 scale MPH.  And as other posters have noted, locos designated by Lionel as "switchers" employ a different speed table, where each step represents a slower speed than it would in a main-line road engine.  Some DCC decoders allow the user to create their own speed table.  Barry might know whether PS3 allows this under DCC operation.

(2) Most of the "better" Legacy locos, including the FEF, have back-drivable gears.  This means the wheels can turn the motor.  It also means that the weight and momentum of the train help to keep things rolling smoothly at all speeds.  This is especially important in dual-motored diesels, where the two small motors are able to "help" each other.   If one motor stalls momentarily, the other can "push" it.  It also reduces bucking when going downgrade, or when double-heading two locos with slightly different gear ratios.

Most Postwar locos had back-drivable gears; Lionel re-introduced them around 2007.  In my opinion they confer a worthwhile improvement in operation; I would like to see MTH adopt them too.  

MTH could also design their new locos to have a 2-piece chassis, with a separate gearbox, and removable wheels and axles.  This would make it easier to install a higher-ratio gearbox for slow speed operation, to replace the rubber-tired wheel sets with steel ones (or vice versa.)  MTH's HO steam locomotives are built this way, as are some Vision Line locos, and expensive brass models in all scales.  

Many of MTH's designs are about 20 years old, and were based on "toy trains" made up to that time.  Now it's time to retool, and make the engineering improvements needed to maintain parity with the competition.

gunrunnerjohn posted:

I don't have 66 feet of a straight to do the test!

Do I have a typo somewhere that I can't find?  it's 66 inches.  

Ted, hit a couple good points here.  Gear ratio matter, and type of gears.  Also when going for scale speed versus undetermined but consist speed.

I can smooth out any MTH engine at low end, buy changing tach tape to one with a few fewer stripes.  1 SMPH will be jerk free, but it won't be 1SMPH.  It will be slightly faster.

Or upgrade a Williams brass that had a 40 to 1 ratio, vice the 20-25 ratio of MTH and you will have a very slow moving train, but no top end if you want to highball that GS-4 or J.

Both manufactures are limited by the upper voltage available.  For Lionel 18VAC, for MTH 22 to 24 VAC or DC.

MTH has not refined gear drive like Lionel did.  Lionel gearing in the Legacy diesels and probably Steam too is a different drive system and has smoothed out the mechanical end.

Tach read segments also effect the amount of change available.

If you watch an MTH motor maintaining 1 or 2SMPH it rotate and stops,  It is not the sweet spot.

I need to measure some gear ratios on Lionel.  I have some recorded for MTH/Williams because of Upgrades I do, but have not measured any lionel.

I do believe, at least ERR Cruise that the first notch is faster than 1 SMPH though.  G

For ERR, it depends on the gear ratio how fast the first notch is.  In general, I'd put Legacy low speed performance first, with both PS2/3 and ERR Cruise a close second.  I believe you should be able to be happy with the performance of any of these systems, and I personally don't pick between them based on that small nit.

What John said. 

[back-drivable gears]

They are a problem if you are pulling a long train downhill. The load behind will push the engine faster than you want. I had a grade with a curve at the bottom and my PW Berkshire speeded up as the cars from behind accelerated  the engine with the voltage off until it de-railed off the curve.

No more back-driven gears for me!

The PW Berkshire is a long ways from the Legacy locomotives we're talking about.  I've never heard anyone that had this kind of issue before.  What kind of grade were you running it down, 10%?

Joe, if your PW Berkshire had one of the modern "cruise control" electronics packages, the motor would resist speeding up on the downgrade and act like a brake.

graz posted:

Joe,

The Hudsons look great!

Just curious  - why are the smoke units behaving differently? One's smoke dissipates quickly while the other's hangs in space much longer.

 

They have both MTH and Mega steam oils in un-known quantities (mix ratio?). One engine is a brand new PS3 and the other is a used PS2. I think all this matters.

gunrunnerjohn posted:

The PW Berkshire is a long ways from the Legacy locomotives we're talking about.  I've never heard anyone that had this kind of issue before.  What kind of grade were you running it down, 10%?

It was on my first layout back in the early 60's with Lionel track and 0-31 curves. The grades were the same as the Lionel graduated trestles but extended up farther on a 5 x 12 layout. The 0-31 curve at the bottom was the problem as the engine picked up speed with 10 freight cars behind even when stopped at the top with this long down grade.

Joe the gear ratio in the postwar Berkshire is hopeless, somewhere around 8:1.  Also universal "Pullmor" type motors are much more sensitive to changes in load, compared to a modern "can" motor.  The poor speed control characteristics of Postwar steam is the #1 reason I switched over to scale-sized trains when I did.

Newer Legacy steam are geared about 18:1, and the double-cut worm has a lot more built-in braking ability than the triple-cut worm on your Berkshire.  If you tried a Legacy Mikado or Pacific, even with Odyssey speed control turned "off"  I believe it would be a revelation for you.  

GGG, I think Williams had the right idea with their 40:1 gearbox.  After all, how long is the average straightaway on a home layout?  Not sure about the OP's GS-4, but most of the Premier steam I've taken apart were geared at 16:1.  With a top speed north of 100 scale MPH, that's too fast.  I actually replaced the original Pittman motor in my PS1 Hudson with 24-volt version of same and it runs better now at half the speed.  I would have preferred to change the gearbox but I can't because it's built-in! 

There's another problem with the self-locking gears used by MTH.  Despite advertising a flywheel, the early Hudsons (20-3020) and USRA Pacifics don't coast worth a darn.  When I run these locos on our club layout, I never let kids handle the remote. (We are running TMCC in conventional mode with Powermasters) for fear they will push the "DIR" button and bring the whole train to a rod-graunching halt.  This has happened, and I often worry that the driving rods, the hex screws holding the rods, or even the all-important axle gear will be damaged by the weight and momentum of the train pushing against locked gears.  Again rubber tires are part of the problem, because the loco cannot slide as a real one would.  Of course there's no way to replace those grooved wheels with tires, because the locos have a one-piece chassis with captive axles.   

Lionel was very wise to change the gearing in their premium locos.  MTH would do well to follow suit, and/or make the other changes that I mentioned above.  I have plenty of mousetraps already, I don't need another.  What I want is a better mousetrap!

gunrunnerjohn posted:

I believe you should be able to be happy with the performance of any of these systems, and I personally don't pick between them based on that small nit.

MartyE posted:

What John said. 

What John said, also.

This thread conversation is getting into "how many angels can dance on the head of a pin" territory. 

Gentlemen,

     In reality the engineering in these toy trains is just fantastic, both Lionel and MTH have great slow speed products today, I own and operate both, my new Legacy Northern Pacific GP9 crawls along with a full consist, my P2 263E Tin Plate Work Train does the some thing. I am just glad both companies produce such a fine engineering product.  Marty you do have point, I have noticed the same thing, however some people say the same thing about me, when I voice my opinion about CW-80 Transformers.

PCRR/Dave 

Calling MTH and asking them to diagnose his problem over the phone is not the same as taking it to a service center and having them check it out.  There are a number of issues that could cause this, none of them designed into the product by MTH and most of them correctable. None of us can solve this for him without eyes on the problem.  Marty's request for a video was ignored. Seems we are devoting too much time on this topic given the situation.

George

George S posted:

ironlake2 posted:

 my dcs proto 3 premier sp daylight at speed steep 1 runs very slow but super jerky 

There is something wrong with your engine.  Other PS3 steamers don't do this.  Take it in for service at your LHS.

I did and mth said this is normal for speed step 1 and 2 and sent it back.  Also I have no way of posting video as I do not have a video camera.  and in response to your coment on the legacy 844 it runs super slow and smooth on speed step 1 and is just a great engine.  You comment on never run on speed step 1 is out to lunch, but then you said your experience with legacy is very limited.

Mth dcs came out around the late 90s and is now 16 years old and needs to be improved.  I have yet to see a change in 3 rail operation and sound quality is also below par to lionel legacy.  MTH needs to improve the system.

Still beating up on MTH just to be a troll, Ironlake2?   

It gets old after a while.