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

[SkipGear]

I'm baffled by the complaints of "too much light under the boiler". The problem with most N scale loco's is that there is not enough light. The boiler is a separate assembly setting above the engine bed of the loco. They should not be joined in one big glob. There is supposed to be light between the boiler and the engine bed.


http://ogrforum.ogaugerr.com/fileSendAction/fcType/0/fcOid/17479526148760778/filePointer/17479526148760795/fodoid/17479526148760786/imageType/LARGE/inlineImage/true/NKP%20765%20at%20%20Altoona%20Station.jpg

Not the greatest video but you can see how open it is between the boiler and frame. The only thing that needs to be between them is piping and clutter, not a solid view block.

[SkipGear]

Another video:

The more I look at these, it is a problem of perspective more than anything. Our eyes are generally set farther apart than the length of the model locomotive. We will never have the same perspective as looking at the full size loco from effectively one point. On the model, we are looking straight through and the spring castings and such tend to line up and hide behind each other, making the loco look "lighter". When you look at the full size loco, because of perspective, you would only be able to line up at best, one driver in line with your eyes. The other drivers and suspension are effectively wider and block more of the view as the angle away from your point of view increases.

It's probably not the best way to explain it but we just can't look at our models in the same way you can the real thing unless shot through a camera at scale distances and even that is not accurate.

[sizemore]

Skip,
Those are pretty awesome vids!


The S.

[nickelplate759]

Here's a puzzle:

Last night I was working on stripping the whitewalls off my Berkshire's drivers.  I was running it upside down in a cradle, and holding an exacto blade against the white paint to scrape/chip it off.

The good news is that this works, and I like the looks much better.  The bad news is that after doing the second driver, the Berk stopped running.   Everything else still worked - sound, lights - but no motion.  I did check for binding in the rods and didn't find any.

The puzzle is that after I stopped work in frustration, watched the Timbers trounce FC Dallas, and reset my DCC system (Sprog II), everything magically worked again!

Running a knife on the driver does load it down, and a couple of times I stalled the engine.  Does the Bachmann DCC have some kind of overload protection?  I didn't notice the engine getting hot, but with a metal boiler I might not.

Regards,
George

[peteski]

No idea if they installed them on this model but Bachmann-s 44-tonner does include an electronic circuit breaker wired into the motor circuit. It is a small yellow disk-shaped component which is supposedly there to protect the tiny motor from overloads.  I suspect that it is some sort of a thermistor which will get warm when too much current goes through it and will shut down the motor circuit until it cools down.  It is only a speculation (about how it works) as I never tripped it).

[SkipGear]

Tsunami decoders have a thermal overload protection in them. That may be the case also.

[mmagliaro]

I would say that if you completely stopped the drivers with the knife blade, that's a really bad thing.  Forgetting about the decoder, that means you are being awfully hard on the gears and the motor.   I'm sure you didn't mean to stall it.  But I suggest maybe a different technique for scraping off those white walls.   Try angling the blade back as the wheel rotates under it.  The chances of jamming the wheel on the sharp knife edge are much less.

I've done this on other engines like the Bachmann 2-6-6-2, and it works well without locking the wheels.

[mmagliaro]

// Edited for grammar //

So now I have a Bachmann 2-8-4 here to fool around with.

The drivers are spaced apart by .040" more than the LL Berk, which is quite a bit when you think about how thick a piece of .040" styrene is.  The drivers themselves measured the same as the LL engine within a few thousandths.  I don't really like the wide spacing.  I think, honestly, that between that and the white tires, it looks like an old "American Flyer" engine, even though the rest of the body detailing is quite excellent.

As for the hitch in the motion, yep, this one has it bad.   I bypassed the decoder and ran it on plain DC.
The hitch is not a DCC induced problem.  It is mechanical.  Just running it until it hangs up and stops, and then using the old "wiggle the siderods with tweezers" test, it sure seems like a basic out-of-quarter problem.   The rods bind up tight at that spot in the rotation.   With a string of cars, it runs like you're tugging on the end of a string: yank-yank-yank.

I wouldn't say the pulling is great.  It's okay.  It can pull 30 cars (and probably more) on level track.  But up my 1.7% grade, it can't pull 20. That's pretty bad because, after all, who has a perfectly flat layout?   A superpower steam era engine like this ought to be able to pull more than that and not go into full slip on a 1.7% hill with 20 cars.
It also isn't too great on motor power.   At about 20 mph, it will slow down on the hill to a complete stop unless I juice the throttle (and then eventually, it will go into full spin when most of the train gets onto the hill).

I'll see how it runs when I correct the quartering.  First, I have to pull all the rods and see if it really is quartering.

I am not here to bash Bachmann.  I'm just telling you what I see when I run this.  The owner is letting me try it out
and maybe do some adjusting and fixing on it for him.
But I will say this.  If I had paid $200+ for this engine, I'd consider it completely unacceptable and I'd be sending it back.

[Chris333]

I really need to hurry up and put mine back together to sell it at a loss. Before I forget about it and end up with another box full of dollar signs.

[peteski]

I really need to hurry up and put mine back together to sell it at a loss. Before I forget about it and end up with another box full of dollar signs.

It's that good, eh?   

[Chris333]

It's that good, eh?   

For an NKP C&O or PM Berkshire it would be worth fixing up, but for the start of a kitbash it doesn't look worth the trouble. 

[jdcolombo]

So now I have a Bachmann 2-8-4 here to fool around with.

The drivers are spaced apart by .040" more than the LL Berk, which is quite a bit when you think about how thick a piece of .040" styrene is.  The drivers themselves measured the same as the LL engine within a few thousandths.  I don't really like the wide spacing.  I think, honestly, that between that and the white tires, it looks like an old "American Flyer" engine, even though the rest of the body detailing is quite excellent.

As for the hitch in the motion, yep, this one has it, bad.   I bypassed the decoder, and ran it on plain DC.
The hitch is not a DCC induced problem.  It is mechanical.  Just running it until it hangs up an stopping, and then using the old "wiggle the siderods with tweezers" test, it sure seems like a basic out-of-quarter problem.   The rods bind up tight at that spot in the rotation.   With a string of cars, it runs like you're tugging on the end of a string: yank-yank-yank.

I wouldn't say the pulling is great.  It's okay.  It can pull 30 cars, and probably more, on level track, but up my 1.7% grade, it can't pull 20, and that's pretty bad because, after all, who has a perfectly flat layout?   A superpower steam era engine like this ought to be able to pull more than that and not go into full slip on a 1.7% hill with 20 cars.
It also isn't too great on motor power.   At about 20 mph, it will slow down on the hill to a complete stop unless I juice the throttle (and then eventually, it will go into full spin when most of the train gets onto the hill).

I'll see how it runs when I correct the quartering.  First, I have to pull all the rods and see if it really is quartering.

I am not here to bash Bachmann.  I'm just telling you what I see when I run this.  The owner is letting me try it out
and maybe do some adjusting and fixing on it for him.
But I will say this.  If I had paid $200+ for this engine, I'd consider it completely unacceptable and I'd be sending it back.

Hi Max.

Anxious to get your "fixes" for this engine.   Two of mine still have a bit of a hitch, which is worse in reverse than forward, despite my attempts to correct the quartering.  I'm beginning to think that the valve gear linkage just has so much "slop" in it that getting absolutely smooth running is going to be a futile effort, although the one I have converted to an ESU LokSound runs OK and sounds great (!).  Too bad I had to pay twice for a DCC/sound decoder . . .  It's really frustrating.  The detail on the engine is excellent; the "operating" (more or less) Mars light on NKP 759 is a big plus, and the electrical pickup from the tender seems absolutely bullet-proof.  The pulling power is OK for me (I happen to be one of those people who has an absolutely flat layout - the area from Fostoria, OH to Rocky River just west of Cleveland just didn't have a lot of grades . . . ), so if I could get the thing to run really smoothly, I'd be pretty happy, although I too have noticed that the motor seems less than robust.

Sigh . . . I had such high hopes for this engine . . .

John C.

[mmagliaro]

It's that good, eh?   

Ha!  Made me laugh, man.   
Seriously, it's a matter of how many of them have problems like this.
The motor power issue and the wide driver spacing bother me.   Those things can't really be "fixed". 

[sizemore]

I'll see how it runs when I correct the quartering.  First, I have to pull all the rods and see if it really is quartering.

Last week on my test subject I yanked all the rods and wheels and did a complete quartering job. All the drivers including the third driver were out a tad. I re-quartered them all and it has no hitch without load. With load I get the surge-yank-yank and it likes to walk side to side a little. I could probably change the CV's for BEMF to cut it out but at this point I'm ready to chuck them up on the bay get at least some dineros back.

The S.

[mmagliaro]

sizemore:  Good info.
I am hoping the quartering isn't that bad when I get to working on that aspect.

I've had this one apart a little.  First off, there's an issue where the siderods will jam if the front driver is allowed
to move all the way side to side.  TopHobbyTrains even has a youtube video on this and they even show a "fix" for it wherein they bend the side rod between #1 and #2, on one side only, which effectively shortens the rod distance between those two drivers.  I put a shim down in the axle cavity so keep the front axle from moving too much side-to-side and that also fixed it.  It can cause a hard jam in reverse.  I'm sure it doesn't happen on every engine.

That had a pleasant side effect.  Although I'm sure I gave up some tigher-radius running (who cares?), by limiting driver #1's lateral play, the engine stays more centered on the track, and it could just barely get my 20-car test train up the hill (with some slip).  It couldn't do that before.

Still runs flippin' lousy though.

While I had the cover plate off, I ran it at low speed and watched it run.  The main idler between 2-3 is nasty.   It just wiggles and wobbles all over the place. 
It spins on a pin that is cast into the right-hand frame half.  But the metal nub on the left-hand frame half that is supposed to limit the gear's side-to-side play is a misshapen blob, and the gear itself wobbles on its pin way to much.
Sigh.  The parts, the tolerances, the fit...  It just ain't Kato. 
I am going to try making a shim of some sort to slide down in next to that gear so that it will stay put and stay vertical without so much wobbling.  That may help everything run more uniformly.  Then again, I may find that the mechanism can't run at all without all that slop in it.  We'll see.

It definitely has a bad bind at 2 spots in every rotation in forward, and 1 spot in reverse.
And remember, the decoder is not in this engine anymore.  These symptoms are all from the drivertrain itself.