Info re Bachmann K-27 from owners

haha, oh.....choke.......

"An issue you will likely never encounter. The K27 has a top speed that is very similar to other plastic models built by companies such as Aristocraft, LGB, Charles RO and others. This top speed is twice a K27 prototype speed and much faster then many comparable brass models. While the prototype modeler likes the slower speeds, the market still demands the faster speeds. Most of us use the after market electronics we have chosen to adjust our top speed to suit our preferences.

The K27 has a very large motor and some electronics in the market have problems powering the motor/gear mechanism. Comments such as a sluggishness, poor acceleration or stuck in third gear are an observation of a poor marrage between the drive and the electronics. Other electronics in the market is designed for high efficiency drives and the power is smooth across the speed range. I have used Lenz, QSI and ESU drives in my K27s. All have high frequency back emf as part of their design and none have any of the problems reported by Matthew. In fact several sound manufacturers had to slightly alter their software to accommodate the ultra slow performance that is achievable by this model. '

NOWHERE does he say it's wrong.
What he does is waffle on about "the market still demands the faster speeds".
And, that like Bose speakers, some manufacturers have "slightly alter"ed their software.

The gearing was supposed to be 29 or 30:1.
It IS 14.5:1.

Find me another steam loco with that gearing.

Toys, maybe, but certainly not 1:20.3 scale models!

One thing you may not have noticed, I have been working this problem for some time now.

I have copies of more stuff than even I can believe.


Stanley has many time said, in print, there is no problem with the gearing.
If 14.5:1 is okay, why not do away with gears altogether?

Remember:

Read with comprehension!

Posted By Marauderer on 09/03/2008 2:01 PM
Posted By Curmudgeon on 09/03/2008 9:10 AM
Another one failing to grasp the issue.
It isn't really worthwhile trying to explain it.
However, suffice it to say, if you follow Stanley's reasoning, we don't really need gears at all in our trains.
Rather, some new dcc control system, and the wheels connected directly to the motor shafts.
I am seriously puzzled by the total lack of any understanding of engineering and design principles shown by some.

That is pure bull on your part. All I got from that is that Stan felt the K 27 was geared wrong. No where did he say that gears shouild be done away with. Whats up???" border=0>




Oh, and telling me my comments are pure bull is not really productive.
I may be outspoken, and hard to get along with, but "bull" isn't part of the equation.

I did.

MANY years of experience showed about 30:1 with a 19V Pittman was ideal.

This engine is half that.

Because of that, the current "curve" is outside the normal envelope, i.e., while it will haul 28 cars on level track (do it), at 20 on 4% it exceeds 3 amps by so much it trips the output protection on the throttles every 4 feet.

Done it.

I know full slip is over 4 amps.

Elitist?

Really?

There is one person on this thread who qualifies as "elitist", and it i neither you nor I.

And, all of that said, the locomotive is fine within the confines of the limitations.
You stay inside something reasonable (like, say, prototypical loads on prototypical grades) you'll probably be just fine.

Personally, I don't like the current spike.
Nor 11/16" side-play at the pilot beam.
Nor cab doors that won't stay fully open.
Nor optical chuff triggers that don't work out of the box, nor wimpy yellow LED's and the need to re-wire to use incandescents.
Nor 13 wires between engine and tender (I cut out 5).

I know what was proposed over a year ago on the motor and gear ratios.
I have a fair idea of what was actually happening behind the scenes.

And, I'm not interested in doing any more to help sort out their issues under the current arrangement.

Waiting isn't going to accomplish much.
The "second run" of K's was originally scheduled for this fall.
That seems to have been supplanted by the Liver Spot.
The locomotive is what you get.
The fixes are easy, and if you don't run sound or don't care about bright incandescent-glow headlights, doors that open all the way, and have lots of side clearances with little grade or short trains, you're set.

The "fixes" are published.

I wasn't "involved" per se.
I was asked about motors and gearing, which I wrote a full report on (still have the original).

For 11-1/2 years now, I have been involved (on my own time and dime) with generating field fixes to keep locos running.
I tried to generate them in such a manner as to be able to be accomplished by the average modeler.

"Biggies" I have always run past Philly Phirst, to let them have a shot at their own "fix".
The last one, they sat on it, and it was released, including the "Model A" shim use (from the old shims when I had a Model A) to someone else to release, and I don't work with people who do that.

This is what was submitted:

K-27 motor proposal 12JUL07


I have in my possession for evaluation two Pittman motors for the upcoming K-27.

I have evaluated these motors, not only on their stand-alone merits, but based upon much experience with Pittman motors in Large-Scale locomotive.


Barry Olsen of Barry’s Big Trains uses Pittman motors.
I do R&D work with Barry on new chassis.
Much trial-and-error has resulted in a 19V motor that works with all applications.

The motors in hand are a 9234E847, 15VDC, and a 9234E848, 19VDC.
Follows is pertinent data:

9234E847 9234E848

Torque: 6.1 oz/in 6.1 oz/in

Stall Current 12.1A 10.1A

Continuous current 2A 1.7A

Max no-load speed 6150RPM 6150RPM

As you can see, the 15VDC motor will handle more current. The 19VDC motor will be a good “compromise”.
Be advised there is a 25-26% overload feature in both, so the 19VDC motor will function fine on 24VDC.
The 1.7A continuous rating of the 19VDC motor is about three times what any of your other engines draw.

Working with Barry, we discovered a 30:1 gear reduction was best for prototypical speeds. I would not want to see much less than 26:1, as we don’t need folks flying these big locos off curves.

The 30:1 works well with Barry’s use of Bachmann 4-6-0 2” drivers, as well as the 1.75” drivers on his 2-8-0.

I would suggest a double-lead worm with a gear reduction to obtain the desired end ratio.
Double-leads eliminate “worm lock”, yet can retard runaways on downgrades with heavy loads, something a gearhead motor with bevel gears on the axle are unable to accomplish.

Discussing this with Barry, he advises me that his new replacement gearbox and motor for the 2-8-0 Bachmann Consolidation is ready for production after having been field tested.

He also states that he would be willing to discuss with you sharing the use of the development of this new gearbox, which has ball-bearings on each shaft, and quite beefy gearing.

The 9000 series motors I have will bolt into this gearbox and fit his worms.

You need to discuss details with him.
++++++++++++++++++++++++++++

Since nobody runs at 6,000 or 10,000 RPM, the motor speed through the gears to the driver diameter governs speed.
Obviously, they missed the mark, and I know why.
Want that published, too?

And, you're right.
You DON'T know.

Posted By gregcoit on 09/03/2008 11:48 PM
Stan Ames said it's hard to guess what max speeds the modelling public wants (again remembering how diverse we are). But I think the prototype itself offers some basis to make that decision - a 1:32 F or E unit should be able to operate at some decent scale speeds. Not so much for a 1:20.3 NG steam locomotive.
BTW - I'm not arguing with Stan Ames in any way - he's not the guy who made the decision. Just giving my 2 cents, if it's worth even that.... " border=0>
Greg Coit
Arcata, CA




How do you know he didn't?
You might just be amazed at what may or may not have been claimed at one time or another, what's in print, and what the truth really is.
Nobody wants to argue with Stanley.
It's pointless.
Just be very careful to understand what you THINK he says in a response.

Bob- Thanks.
Glad to see you were able to get a long post up.

Stanley-

Now what are you going to do?
Call Clambake and get Bob fired?
Gee, can't do that.

Complain to Howard Lee and get him pitched?
Gee, can't do that.

Get someone on the East Coast to ignore the polish on his shoes long enough to demand a re-review?
Gee,can't do that.

Tell everybody Bob doesn't like DCC and is picking on someone's choice of control systems?
Gee, can't do that.

Stanley, you stuck your nose in where it didn't belong, utilizing skills you didn't have, and you alone stand responsible.
Now you're involved with the Liver Spot, and God alone knows what you've done there.

Thank Heavens you were successful in getting me pitched.

I feel no strong urges to sort out your mess this time.

And, please, stop with the e-mails and phone calls.
They will NOT be answered.

I did not self destruct.
If that's your view, stuff it.
I will let you figure out where.
I put in 11-1/2 years fighting prima-donnas, and I certainly don't need any more.
Fighting or prima-donnas.
You wormed your way into the Pholks at Philly, and look what we've got.
Read Bob's post, if you want a dcc version of the issues.
Obviously, since I use a system different than dcc, I am not qualified to evaluate the units, nor write reviews.
I cannot wait to see how your influence has affected the next loco out of the shed.
Self-destructed?
Boy.
You don't understand mechanics, nor electronics, and you certainly do not understand what was happening.
Personally, I have determined that as long as you are involved with this company, and that includes making statements for them, I will not purchase anything from them.
That's my opinion.
I have no intention of encouraging anyone else, publicly or privately, to either purchase or not purchase products from said company.
That said, look at the comments from folks waiting for the "next run" of K's.
While Marketing and the ecconomy may have something to do with sales, when even staunch dcc-users come out with huge posts on "issues", you become a lone voice (added to your particular shill following), and we all wonder if the consumer isn't looking at all the comments from actual owners before deciding to buy or not.
Remember the counterweights.
While I am trying my darndest to get them to look at the issue and allow publishing of a field fix, all I am hearing is "Stanley says there is no problem".
That is, until you had an engineer look at it and confirm what you had fought against.
I have other things to do now that do NOT include the company in question.

Posted By bobgrosh on 09/05/2008 1:25 PM
TOC, I think you are being too hard on Stanly. I actually liked the idea of a standard socket. Stanly tried to introduce a standard that expanded on an existing proprietary socket. He assigned the purpose that each pin was to be used for, including several pins that had been unused in the proprietary socket. 


You have no idea, and I am by NO MEANS being "too hard" on poor old Stanly (sic)


Stan has said, several times, he is not an electronics engineer. It was Bachmann's responsibility to implement the standard. 

And, Stanly (sic) advised them......


Bachmann did not seem to understand the basic concept of DCC plug and play sockets. 

BINGO!


Most manufacturers seem to adhere to a simple concept.

The purpose ..... is to connect the motor and lights to the track using the standard pins on the interface. A lighting board may also have electronics to provide directional, constant or special lighting effects like mars lights. 



Remove either the dummy board, or the lighting board, and you expose the rails, motor and all the lights so that you can install a decoder. 



There is a small dummy plug. Remove it and all the wiring in the loco is exposed on the pins of the interface. The motor and lights are no longer connected to the rails, or anything else for that matter. 

Now compare this concept that nearly all other manufacturers do to what Bachmann did. 



Bachmann started with a very ambitious DC lighting board. They included flashers for the firebox. current regulators for LED lighting, Optical chuff, etc on their lighting board. The tried to incorporate a set of standard pins for a decoder (generic) interface. Unfortunately, the pins are not in the right place. (electronically the right place) Instead of being between the DC lighting circuits and all the hardware, they are inputs to more circuitry they added  as an additional interface to external decoders. When you remove the dummy plug, you are not disconnecting all the DC lighting circuits like the small scales or LGB. Instead, you are removing just the bridge rectifier that provides raw DC to the DC lighting circuits. The fact that you removed the bridge is testimony to just how badly Bachmann failed to understand the basic concept. As soon as you remove the dummy plug, you expose the INPUTS to their hardware interface, ( NOT THE REQUIRED HARDWARE) 

Of course the interface will no longer work because it no longer has a power source. You now have to replace the bridge rectifier you just removed to power the interface which sits between you and the hardware you need to control.



It gets worse...


Really?

The DC lighting part of this mess is designed for a fixed set of devices. It will only drive the provided LED's or electrically identical LEDs. Want a brighter LED? You can't have it. Want a five volt or 24 volt bulb, Sorry! Don't want a rock convert light show in your firebox. sorry but you are stuck with it. Most modern decoders have realistic lighting effects. They are designed for incandescent light bulbs. You can drive an LED, but it will not look anywhere near as realistic as a bulb. A bulb will average the pulses sent by these effects and GLOW at whatever the brightness the effect requires. LED's are either on of off. They do it so fast they SORT OF fool the eye into thinking they are dim, but the effect is not  the same. Look a bulbs driven by a rotary beacon effect from a Digitrax decoder and it looks like the bulbs are actually rotating. Connect LED's instead, and it looks like one of those cheep lighters from the quick mart. Worse still, the pulsing patterns on LED's, while too fast for the human eye simply can not be video taped. Take several photos with a digital SLR using a fast shutter speed and that "Dim" LED headlight will show up at full brightness in some shots and totally off in others.

Show the picture to a friend and he'll say" what happened to the headlight, it's not working. Now, Stan and others CLAIM this mess works, but you have photographic evidence that it does NOT.

****, I know.
I was gutting them before you ever got one!


OK, so I am too particular. I expect too much.

Yep, I admit it. I want a simple interface that exposes the hardware to a set of pins. I do not want a super fancy DC lighting effects board with a do everything battery, RC, Air-wire, DCS, Analog DC, anything but DCC interface.



And Yes, It pisses me of that those who don't want all that electronic car call it a DCC interface, It is everything BUT a DCC interface.



I am a DCC user and I do not like being forced to pay for expensive stuff that adds cost, I can't use, doesn't provide any benefit, has to be ripped out and thrown away.



I'm really lusting over that mallet. Someone talk me out of it.







Gee, Bob, I can't wait for you to tell us what you REALLY think!
If you only knew the extent of Stanley's involvement in all of this......and the latest falderdash......

Just a note:

While operating tonight, I ran my K for a while.
I widened on 'er, wide open at 14.4V of battery.
It became a 1-4-1 at the first #4 turnout.

Read my post about it a nice engine.
Read others postings about how it could have been a nicer engine.

IF we had correct (or, closer) gearing, IF we didn't have to deal with the Ames Super Socket, or the "With Integrated Production Electronics", or the 13 wires between engine and tender, early units with counterweight issues, red class lights, impossibility of just placing an incandescent bulb in without rewiring, very small surface mount electronics impossible for the average hobbyist to repair, 11/16" of side play at the pilot beam, the jet-blast-roar of the fan on battery or dcc, inverted chuff that needs "modification" and still won't work at low track voltages without MORE modifications that preclude the use of the smoke unit, silly things like doors and holes in the sides of smokeboxes, then, yes, worth every penny.

I've fixed all the issues on mine, and probably a dozen others, and they all run fine.

This could have ben a home run.

The pinch-hitter they brought in appears to have not been up to the task, and has been successful in one thing.

Getting the person who kept the locos running not wanting to do it anymore.

But, hey, the pinch-hitter is more than capable of finding folks to do a better job.

Just remember, if the stuff was built without any problems, we wouldn't need to fix them, and look at all the fun we'd miss out on.

It IS a nice loco.
Don't mis-understand me.

The push was for a home-run, and for simplicity.

If you followed older threads (now probably in the archives), I had a counter-proposal for screw terminals at one end of the tender, on the floor, that ANYBODY could connect virtually anything to.

With the limited space in the next announced engine (two vertical motors, 21MM of height for a speaker, and whatever version of Ames Super Socket) plus smoke unit, weights, any other electronics, and a flicker board, I would be willing to guess someone in the organization is re-thinking the screw-terminal approach and re-evaluating why anyone listened to the socket promoter in the first place.

While the K was a good candidate for "cut and throw", from what I have seen, the next big one is almost a mandatory.

I had to re-shuffle my boxes and bags of cut out locomotive electronics earlier in the week, and it's getting to be a problem storing this crXp.

But, there is a reason I keep it.