Bachmann 2-8-4 Berkshire/Kanawha in stock at M.B. Klein

[wcfn100]

What I don't understand is why the Berk is so inferior to the EM-1 or 2-10-2 or 2-8-0.   Do they make those in different factories?  Different production lines? 

The EM-1, 2-10-2 and 2-8-0 are all Spectrum units.

This appears to be from their POS line like all their diesels, freight cars and non-Spectrum steam. 


Jason

[mmagliaro]

John, I wondered that myself.   Maybe there are 2 different teams at Bachmann who do engine designs.
Maybe they operate like Apple did back in the early days where they had two competing teams within the company to spur a competitive attitude.

I think the problem is that their design practices, manufacturing tolerances, and QC are still not really very good.
But mainly, it's their design practices.

If you look at the EM-1, as much as people are happy with it, it has issues with rod jams and other quirky things that
are caused partly by sloppy tolerances and partly by the design of the parts themselves which make it more
likely that they can be assembled with a problem.  It's just that on the EM-1, they "got away with it" and mostly everything fits and works.   On the 2-8-4, they weren't so lucky.

Look at the Spectrum 2-8-0.  It's a great running engine.  But... driver one is designed with enough
side-to-side slop that it can jam the pins on the valve gear, especially if you gauge it correctly.
That is caused by the way it was designed, not by sloppy assembly.   The parts are designed to fit that way,
with insufficient clearance between the #1 crankpins and the valve gear.
The only real way to fix it is to add washers to limit the side-to-side play of driver #1.    A smart designer
would limit the driver #1 play ANYWAY, because they know it rides right behind the valve gear.

The wheelsets being out of gauge.   Seriously?  In this day and age, Bachmann cannot design a jig to assemble
their drivers and wheelsets that keeps the wheels the correct distance apart?  I mean, come on.  I'm not asking for much here.  Make the wheels the same distance apart as the (*#)(*@  RAILS.  That's kind of a basic idea for making
toy trains, isn't it?

Let's look at this 2-8-4 issue with the quartering.  What if they had just chosen to make drivers 2, 3, 4 geared, and driver 1 only run on the rods, and #2 and #4 run only on the gears.   That would require just one more idler and geared axle.  Yet it eliminates a whole host of aggravating precision problems related to quartering.
That's what Kato did on the Mikado.

Peteski, this is kind of what I meant by my earlier remark.  I don't expect Bachmann to ever match Kato's precision manufacturing.  But they are certainly capable of making better choices, like what is geared and what is pinned, so that their models have a much better chance of working right, even allowing for tolerances.  It's like they design themselves into a corner, where everything has to be made much better than they are capable of making it in order for the engine to run right.

[mmagliaro]

Harrumph... I have one final trick up my sleeve.
I'm going to make a new solid siderod to go across 1, 3, 4.  I suspect that this will force #4's crank hole to stay in a straight line with 1 and 3, which will entice that wheel to move around move smoothly.  The way it is now, with the little short rod off #3, it just tugs-and-turns, tugs-and-turns.  The rod holes are much too sloppy to keep it rotating properly,
at least on the one I have.  It is possible to have a wheelset quartered perfectly and still have it get stuck because the rod doesn't follow the wheels, and that's what's happening to mine.

[victor miranda]

this is a paraphrase from charlie vlk.
The locos get a team of people on the project
and you get that they design...

I will add that some teams are better than others.

I understand that b-mann stuff is all from one factory.
I also do not think that makes much difference
because the locos are all so different.

I am not going to be fair in my review
because I can't say some things in a nice way
and say other things in an unkind way

my berk has hitches.
my berk can run pretty slow
... thus I get to see the hitches.
those two things are interrelated...
the loco goes slow enough that you will see small issues.

the motor is efficient and I know my loco will pull 15 and more cars
the loco has a flywheel and looks to be geared at 40 to 1.
the tender has allwheel cone and axle point pick-ups
There are wires tender to engine.

what should have been done to avoid this loco's problems...
the team should have made the tender pickup springs longer.
they should know to avoid building a gearbox with pivots in a straight line
they should never have put the worm on the motor.
last and generally indicating why all the above happened
the gearing at 40 to one is a little low.
it is a small shift is attitude about how all these things interrelate
to create a good loco.
... plus it does not take into account that production items do not easily
 hold tight tolerances.

so the design fails to consider what production will do to the design
AND
fails to consider what the guys who buy them expect from the model.

from here I will be explaining and adding opinions and it
might be a little boring.

this loco is in many ways done well
it has CAPP and a flywheel and is geared pretty low
and the motor is smooth.
the gear train and poorely done quartering just stand out
because... it should be GOOD!
quartering is a production mistake... a misaligned Jig is my bet.
even fixed, there are hitches. this is the gear train.
when you build a gear box. try to avoid three pivots in a line.
it is strange, what happens is the middle gear gets one place where is MUST stay.
that means it needs a good bearing.
another way to say that is the middle gear has two place it will ride
depending on gear rotation...
any gear flaws in the middle gear will hitch twice per revolution

worm...
the gear train? if there is a problem in it...
the worm will move away from the wheel and then snap back into
position once the hitch has passed.

the motor driving the worm... will respond to the added load.
by slowing from the additional load.... this magnifies the hitch.
so off load the worm problem to a pair of worm bearings.

the gear box should be driving the idler gear between the two geared driver/axles
the axles should have bigger gears and the idler should be smaller
this one change alone will get 44-ish to one gear ratio and
would eliminate most of the driver hitching.

my opinions go on like that. it would not take any real effort
to get this loco design to become servicable.
to do that step require the designers to percieve they are not doing 'good enough'
Until they can be made to see the failings, nothing will change.

blame the coreless motor.
without that... you would see the usual 'good enough'

victor

[peteski]

Max, as far as the tight wheel gauge goes, it seems that most manufacturers make them (various degrees) tight rather then in-gauge or even wide.  I have no idea why.  Standards are well defined and readily accessible.

One possibility is that the engineers make the gauge tight in order to make the model compatible with tighter track radius (an old habit left over from the toy-train days of N scale).  Or maybe the majority of N scalers still have layouts with a 7" radius curves!! 

[jdcolombo]

Harrumph... I have one final trick up my sleeve.
I'm going to make a new solid siderod to go across 1, 3, 4.  I suspect that this will force #4's crank hole to stay in a straight line with 1 and 3, which will entice that wheel to move around move smoothly.  The way it is now, with the little short rod off #3, it just tugs-and-turns, tugs-and-turns.  The rod holes are much too sloppy to keep it rotating properly,
at least on the one I have.  It is possible to have a wheelset quartered perfectly and still have it get stuck because the rod doesn't follow the wheels, and that's what's happening to mine.

Please let us know if this works, Max.  I had the same thought.  It is clear to me that the slop in the rod from #3-#4 is creating much of the "hitch" problem that remains in mine.  It's not huge, like it was before I adjusted the quartering, but enough to be annoying, and sometimes causes a complete bind when backing a train (if backing the engine alone, it's OK, but if trying to back a 30-car train, the engine will occasionally just seize up).  If a new solid rod across 1, 3 and 4 fixes this . . . well, I might need to hire you to make me a few.   

Like Victor, I see much that is good in this engine, and it just drives me nuts that there is so much bad.  Given that I've bought 3 of them, I'm willing to invest reasonable amounts of time and money to get them performing as well as they can, rather than putting them on a shelf and writing off the $600 investment.

John C.

[peteski]

John, remind me: do these have true see-through spokes or solid disk centers (like Bachmann 2-8-0)?

[Kentuckian]

Being a C&O modeler, I was really looking forward to this release.  I want to believe.  I will admit that when it comes to food or N scale steam, I am much more of a gourmand than a gourmet.  I guess I lucked out; so far I have only made the CV changes recommended by John C. and those have pretty much eliminated the very slight hitch both of mine had.  I plan on changing the speaker; this seems to be it will give the most bang for the buck, after the free CV, quartering, and guage tweaks.  The sound decoder will likely be there for a long time; I have several "mute" engines waiting for sound.

Why do $35,000 cars come with paper air filters? Why do expensive dress shoes have cheap shoestrings? It seems like everything today needs some tweaking.  I cetainly would have preferred a $150.00 street price for what we have, or better yet a better designed locomotive.  But so far, I am still a satisfied customer.

Thanks to the board for all the comments; I have learned so much.  But especially thanks to John C., Max, and Victor.

[victor miranda]

well, you could think of it as the same thing as  the recent b-mann 2-6-0 and 4-6-0 with a sound decoder....


I know at least a few have said the have good units.
I am glad you posted that.

victor

[victor miranda]

any one know where to get  u joints for one mm shafts ?

I have an idea if I can find that....

victor

[SkipGear]

Victor - Not sure but look at the driveline of a Kato NW2 for the small joints and cups. I just had one apart last night and they are pretty small.

[Chris333]

I'm just glad you guys found most of the same problems I had. Makes me feel less crazy.


My first Bachmann 2-8-0 ran perfect and still does. I've bought 5 more since then and none run as good as my first.

[peteski]

Why do $35,000 cars come with paper air filters?

I know they point you're making but the days of paper filters are pretty much gone (for contemporary cars). They are now made from some sort of non-woven synthetic fluffy stuff. But even when filters were made from paper that was because it was the optimal balance between performance and price.  Paper worked very well as a filter material and it was cheap enough to be disposable (since filters are replaced regularly).
 

[sizemore]

I've bought 5 more since then and none run as good as my first.

They say the first time is the best...  #hadtotaketheshot


The S.

[victor miranda]

Victor - Not sure but look at the driveline of a Kato NW2 for the small joints and cups. I just had one apart last night and they are pretty small.

I have one somewhere... I'll take a look.
thanks