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Improving Our Steam Engines Performance

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Posted by selector on Sunday, November 21, 2021 1:15 AM

David and Wayne, thanks for the information and kind offer.  I will take some time to do some local sleuthing about materials, but I might just take you up on your offer, Wayne.  I'll contact you off list in the next week or three.

-Crandell

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Posted by railandsail on Sunday, November 21, 2021 7:56 AM

doctorwayne

When I bought my first Athearn Genesis Mikado, I was impressed with it's smooth operation, but surprised that it had difficulty going up a not overly-steep grade, even though there were no cars coupled to it.
I later tested it, with a train attached, and found that it could barely move 10 not-very-heavy freight cars on straight track. 

I was starting to regret the purchase, but on a whim, grabbed a piece of sheet lead, folded it a couple of times, then formed it into a saddle, which I draped over the loco's boiler.  Just like that, the potential shelf queen morphed into Hannah the Hauler.  I don't recall the weight of the lead, but it was likely at least a couple of pounds.

That moment convinced me of the need for adding weight to steam locos, although it seemed pretty obvious that it wouldn't look all that prototypical if my locos were running around wearing lead saddles.

There's a thread HERE which offers some info on adding weight to steam locomotives.

Wayne

 

 

VERY interesting link you provided there on working with lead weights. I need to spend some time going over it in detail

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Posted by railandsail on Tuesday, November 23, 2021 6:52 AM

Rubber Band Drives

Old applications,..perhaps needing the injection of newer technologies?

 

Look at how many cars this rubber band engine is pulling,... (BTW the video is speeded up) 

 

 https://youtu.be/SQiZcR1wMk0

 

 

I always heard that one of the real drawbacks of the rubber band drives were their excess speed. But I wonder what newer motor control technologies, etc could do to make things more reliable??

A couple of more videos,...
https://youtu.be/mvFX-jZ6Onk

 

 

 

I was expecting this one to be even faster due to the smaller dia wheel axles, but it almost looks reasonable?
https://youtu.be/ERSbluts29Q

 

 

 

Sure looks like it could be some cheap experimenting !

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Posted by ATLANTIC CENTRAL on Tuesday, November 23, 2021 8:44 AM

railandsail

Rubber Band Drives

Old applications,..perhaps needing the injection of newer technologies?

 

Look at how many cars this rubber band engine is pulling,... (BTW the video is speeded up) 

 

 https://youtu.be/SQiZcR1wMk0

 

 

I always heard that one of the real drawbacks of the rubber band drives were their excess speed. But I wonder what newer motor control technologies, etc could do to make things more reliable??

A couple of more videos,...
https://youtu.be/mvFX-jZ6Onk

 

 

 

I was expecting this one to be even faster due to the smaller dia wheel axles, but it almost looks reasonable?
https://youtu.be/ERSbluts29Q

 

 

 

Sure looks like it could be some cheap experimenting !

 

Your point? The guy has four/five powered units, pulling what are likely light weight cars, on relatively level track. Any four gear drive F unit will out pull them.

As usual, you are looking for a magic bullet for the impossible. You simply ignored everyone who suggested your expectations are unrealistic.

Sheldon

    

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Posted by railandsail on Monday, November 29, 2021 1:44 PM

Your point? The guy has four/five powered units, pulling what are likely light weight cars, on relatively level track. Any four gear drive F unit will out pull them.
Sheldon

I seriously doubt that

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Posted by railandsail on Monday, November 29, 2021 1:56 PM

So forget that rubber band drive subject for now. Lets look at another drive system that's been successfully used in Europe,...a variation on the pusher/helper theme I have been experimenting around with my diesel engined 'disguised pusher/helper'.

Tender pusher

Because I model in N scale this trick has been used often to improve power pulling

With all the mechanisms on hand and diesel frame compatibility with steam tender this seems an easy way to go.

Not so easy unfortunately because of some factors

First you need a perfect stock running locomotives which run flawlessly with a good mechanism, second the synchronization of the speed and gear ratio need DCC to be achieved correctly between the locomotives itself and the powered tender, this is important especially when passing through  turnouts where the tender of the locomotives must no be a pusher  or à puller.

Good achievement were done with only a powered tender pushing the locomotives, a concept used by Fleischmann in most of his N scale locomotives with powered tender only; this ended with powerful and fine running locomotives 

The boiler of these locomotives is full of weight and the running wheels roll without any gears, the locomotives is a full dummy unit. These N scale locomotives like a German BR 44 are far most powerful in N scale than a Bachmann Spectrum 2-6-6-2 or any other US mallet models in N scale 

When seeing the power of a diesel in N scale or in HO this solution need to be investigated more deeply by using a diesel tender pushing a dummy steam locomotives , a quiet easy heavy repowered solution

Tender Driven Pusher
Actually that Fleischmann idea looks like an interesting approach.

Tender driven pushers with unpowered boiler might make things a lot less complicated to engineer and build,...and likely far less expensive to manufacture? Plus good big space for speakers up in the actual locomotive (where the sound belongs).

Brian

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Posted by doctorwayne on Monday, November 29, 2021 2:30 PM

railandsail
Tender driven pushers with unpowered boiler might make things a lot less complicated to engineer and build,...and likely far less expensive to manufacture? Plus good big space for speakers up in the actual locomotive (where the sound belongs).

I re-built two brass Ten-Wheelers for a friend who wanted them re-motored.  The replacement motors were were too big to fit into the locos, though, so I disassembled the original open frame motors by removing the armatures and brushes, and replacing them with a longer drive shaft to the worm.  The extra length projected from the rear of what was left of the motor, allowing me to add a universal joint to each of the shafts, then coupled them to the new can motors, which were laying on their side in the tenders' coal bunkers.

With the motors mostly gone from the loco, I was able to cram both of them full with lead, until they were perfectly balanced at the mid-point of the drivers' wheelbases.  Those little Frankenshteens (not Frankensteins!) pull way over their original capabilities.

Wayne

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Posted by Overmod on Monday, November 29, 2021 7:53 PM

Something common in Civil War-era modeling is to use stiff wire or monofilament as a 'near-invisible' driveshaft between a tender motor and geared and weighted drivers in the locomotive.

I thought years ago that this could be done with a comparatively large motor in the tender, gears to drop the shaft centerline so the shaft could pass through a model stoker tunnel, then gears to raise the shaft line up to a worm as in the approach Wayne was suggesting.

I don't like the general idea of powering adjacent drivers via side rods in models, so this might still involve spur or helical gears between driver axles, with running clearance on the rods to preclude binding.

Much of the space freed up this way could be used for weight over the drivers where needed.  It might be interesting to see the effect of two motors in suitably-sized tenders: one for the drivers, and one to 'diesel trucks' with sideframe swap under the tender, giving more axles of effective propulsion than just a pusher tender alone...

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Posted by ATLANTIC CENTRAL on Monday, November 29, 2021 8:12 PM

railandsail

Your point? The guy has four/five powered units, pulling what are likely light weight cars, on relatively level track. Any four gear drive F unit will out pull them.
Sheldon

I seriously doubt that

 

In case you misunderstood, four powered F units, Genesis, Intermountain, Proto, Super geared Athearn Blue Box, Bowser/Stewart, take your pick, each eight wheel gear driven, suitably weighted as most such locos have been since the 70's, will easly out pull those four or five rubber band drives as shown in that video.

Easily 100 plus cars, likely on 2% grades, without working hard at all.

Sheldon 

    

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Posted by ATLANTIC CENTRAL on Monday, November 29, 2021 8:15 PM

Overmod

Something common in Civil War-era modeling is to use stiff wire or monofilament as a 'near-invisible' driveshaft between a tender motor and geared and weighted drivers in the locomotive.

I thought years ago that this could be done with a comparatively large motor in the tender, gears to drop the shaft centerline so the shaft could pass through a model stoker tunnel, then gears to raise the shaft line up to a worm as in the approach Wayne was suggesting.

I don't like the general idea of powering adjacent drivers via side rods in models, so this might still involve spur or helical gears between driver axles, with running clearance on the rods to preclude binding.

Much of the space freed up this way could be used for weight over the drivers where needed.  It might be interesting to see the effect of two motors in suitably-sized tenders: one for the drivers, and one to 'diesel trucks' with sideframe swap under the tender, giving more axles of effective propulsion than just a pusher tender alone...

 

Could a lot be done to the design of model steal locos to make them pull better? Sure.

But price is already an issue, and honestly, because people like myself with reasonable curves and grades already get acceptable performance, I suspect very few would be motivated to spend the extra cash.

Sheldon 

    

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Posted by Trainman440 on Monday, November 29, 2021 8:54 PM

You know its funny I had the SAME thought as the op 10 months ago, and when I made a post about it, got DUMPED on with criticism. 

Trainman440

I just had a thought about what if tender drives on steam locomotives became common place.

Think about it, it would make producing and designing an engine much easier since steam locomotives comes in all sorts of shapes and sizes, but tenders stay more or less the same, so a similar mechanism can be used for all engines, sorta like diesels these days.

Tenders are also usually just a big rectangle (besides vanderbilts and slope backs) which can just be a huge hunk of metal, and able to fit a massive motor, making them able to pull quite a bit too. 

Tenders also have small wheels, so slower speeds can be more achievable with the same gears and motors. 

Lastly, you can now put the decoder inside the engine, which means sound can finally come from inside the engine instead of from the tender. You could also fit much more inside the engine like smoke units, internal detail, etc. Im personally not a fan of smoke units, but atleast now they wont hinder the pulling performance. (Im sure those who run DC are gonna complain how this point is worthless)

Obviously you wont be able to have slipping drivers, but the infamous binding and mechanical nightmare that comes with using steam locos could basically disappear. No more need for sprung suspension, now all the wheels have to do is be free rolling. 

Now Im not saying this SHOULD be the norm, but I am proposing an alternate world, and how its not as bad as one may think. 

Anyways, just food for thought.

Charles

Okay its not the same idea, but basically the premise is that why dont we have powered cars instead of powered locos?

If you want to read through all the negative comments from that nightmare of a post, feel free.

https://cs.trains.com/mrr/f/88/t/286354.aspx

...and here's a similar post from even longer ago.

https://cs.trains.com/mrr/f/88/t/145956.aspx?page=1

Oh and one more thing, Im not sure about you bachmann 4-8-4, but I realized recently that my bachmann K4 (4-6-2) seems to have lost a lot of its pulling power. The engine visibly slows down dramatically with a longer train yet the wheels arent slipping. Turns out the motor seems to be rather weak* in some bachmann engines (or gear ratio too is too small) and no matter how much weight you add, it wont increase the pull. Weight is not the solution to all things. 

*Or too much friction in the drive despite proper maintenance and lubrication. 

Charles

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Posted by gmpullman on Monday, November 29, 2021 9:05 PM

Trainman440
You know its funny I had the SAME thought as the op 10 months ago, and when I made a post about it, got DUMPED on with criticism. 

Similarly, about six years ago I brought up the idea of having a DCC throttle that more closely resembled a locomotive control stand.

Not much enthusiasm from the replies.

https://cs.trains.com/mrr/f/744/t/254524.aspx

Today, at about $500 a pop, I think Proto-Throttle is selling quite well.

https://www.iascaled.com/store/MRBW-CST

I don't think these forums are the place to find what you might call "progressive thinkers".

Good Luck, Ed

 

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Posted by ATLANTIC CENTRAL on Monday, November 29, 2021 10:04 PM

gmpullman

 

 
Trainman440
You know its funny I had the SAME thought as the op 10 months ago, and when I made a post about it, got DUMPED on with criticism. 

 

Similarly, about six years ago I brought up the idea of having a DCC throttle that more closely resembled a locomotive control stand.

Not much enthusiasm from the replies.

https://cs.trains.com/mrr/f/744/t/254524.aspx

Today, at about $500 a pop, I think Proto-Throttle is selling quite well.

https://www.iascaled.com/store/MRBW-CST

I don't think these forums are the place to find what you might call "progressive thinkers".

Good Luck, Ed

 

 

I would have to agree, this is not a forum full of progressive thinkers.

Personally, I'm not opposed to the idea of tender drives or better pulling steam locos, but I don't have much of a dog in this fight because I am likely on the down hill side of my "locomotive aquisition curve".

I think anyone into operations would find powered cars an operational "problem". 

Proto action throttle - well, I think I have said before, great idea if you are into that. But it's not my thing, not at $500, not at $100.

But back to the idea of progressive thinkers........

I tried DCC, it works fine, it simply does not fit my goals all that well. Or maybe more importantly, it does not make my goals easier, it makes them harder and more expensive.

More expensive or complex steam locos that pull more? I solved most of that with more weight, free rolling trucks, reasonable grades and large curves.

Signals, not to many modelers interested in signals - to me they are esential.

Close coupled passenger cars with working diaphragms that touch? - also esential to me.

Progressive? Who decides what is progressive?

Am I not progressive because I don't like building my layout with foam board?

But I was gluing down my flex track before most people had heard of the idea.

I may not be progressive, in some ways I am no doubt stuck in the past of this hobby. 

But in this hobby, or in other things in life, I don't generally follow the trends or the crowds......

I'm getting started on a DC powered layout, one deck, with deep scenery - talk about going against the trends....... it will have lots of hidden staging.

But my very first layout in 1968 had hidden staging - that seems pretty progressive? Every layout I have built has had hidden staging.......

I tried a double deck layout, I hated it before I could get it finished.......

My HiFi trained ears just can't warm up to onboard DCC sound.......

I designed a handheld throttle years ago that also let you throw turnouts from the throttle - long before DCC, and long before I realized what a bad idea it was.......

Ed, You are a top notch modeler, I have the greatest respect for you, despite the fact that our goals and view of the hobby are likely not all that close, or, maybe they are?

I was just intrigued with your comment, so I had to share my thoughts.

Sheldon 

    

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Posted by Trainman440 on Monday, November 29, 2021 11:40 PM

ATLANTIC CENTRAL

Progressive? Who decides what is progressive?

Atleast in my forum topics' case, I would argue that I wouldve liked to see more comments atleast entertain the idea instead of nearly everyone more or less saying "tyco did that and see where they are now" without considering the fact that we have technology that can make the premise (tender drives) have so much more potential, and that tyco was fundamentally a cheap manufacturer that made cheap, train set level engines. tyco's failure wasent the fact that their engines were tender drive but rather that their mechanisms were cheap performed poorly, and broke down too easily. 

Therefore in my singular case, I would consider progressive to be more open minded. 

----------------------

Sheldon seems to have defined progressive as accepting new technology, and in that case its not this forum but rather this hobby as a whole that's not very progressive. 

It took ages to implement technology in this hobby. First it was the adoption of plastic into locos, then adoption of DCC, then sound. (Im sure there are many more examples beyond these but I cant think of them off the top of my head) Many people (Sheldon here yelling loud and clear that hes one to not use DCC) prefer not to adopt (some of) this new technology. I know some (old) modelers who swear by only running diecast and brass locos, and have a great bias against plastic, even though plastic engines have come so far in terms of detail and quality, and now its basically universally agreed that plastic is just as good. 

Obviously no one should be forced to adopt all the new technology, and I would agree that a lot of the R&D is wasted in much of the new "gimmicks". BLI adding depleting coal loads, markers, and smoking whistles into their big boys seems like a waste. 

Personally I would like to see the R&D to instead be spent on finding ways to make models cheaper, and offer more kit style products...maybe even bring back loco kits. The "do it yourself" aspect of the hobby is lost on many of the new generation, and I feel like I am one of the relative few who has embraced it. 

But Im aware that it doesnt make financial sense for manufacturers to do so, since labor is so cheap in other countries. So Im sure manufacturers will continue to strive to cram more gimmicks into engines, and charge even more for features I'll never use. 

Anyways, my point is this hobby as a whole isnt really progressive, and its not really meant to be. It could be a sign that we've already perfected the way of making RTR models, and now all that's left to do is to expand the list of prototypes (Id love a mercury thats not $1000), and drop the price. 

Charles

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Posted by richhotrain on Monday, November 29, 2021 11:52 PM

Trainman440

Anyways, my point is this hobby as a whole isnt really progressive, and its not really meant to be. 

Charles, I think you got it right. It's not this forum that's not progressive, at least not alone. It is the entire hobby that isn't really progressive. And, as you said, it's not really meant to be. Well said.

Rich

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Posted by RR_Mel on Tuesday, November 30, 2021 1:34 AM

I’m a bit late to the party but I also like plenty of drawbar.  I simply love my Rivarossi articulateds but out of the box their gutless.  The Y6Bs have 2.6 ounces of drawbar and the Cab Forward has 2.8 oz.

You can’t add weight to either without causing the Rivarossi motor to seriously overheat.  My fix is to remoter them using rare Earth magnet can motors then add as much weight as I can.



I use #8 birdshot.  I glue as much birdshot in the boilers as I can, this Cab Forward has 11 ounces of birdshot.  The added weight increased the drawbar from 2.8 oz to 6 oz.

My E7s are made up of a Cary metal body on an Athearn SD40-2 frame using a Mabuchi FK280SA motors weighing in at 33 ounces with over 9 oz drawbar each.  A pair will pull your socks off.



One of my heaver beasts, this one has 11.8 oz drawbar.  Eaily pulls my 3½% grades with a full load of cars.



Mel


 
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Posted by ATLANTIC CENTRAL on Tuesday, November 30, 2021 6:26 AM

richhotrain

 

 
Trainman440

Anyways, my point is this hobby as a whole isnt really progressive, and its not really meant to be. 

 

 

Charles, I think you got it right. It's not this forum that's not progressive, at least not alone. It is the entire hobby that isn't really progressive. And, as you said, it's not really meant to be. Well said.

 

Rich

 

Glad to see my point was clear. the long term nature of the hobby requires that it not be trendy or "progressive" in any rapid sense.

Sheldon

    

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Posted by NVSRR on Tuesday, November 30, 2021 7:32 AM

The British have an interesting solution to this problem of traction.   from what I have seen with experiments some have done on steep helix and steep grades is that it does increase pulling power.  They have even less space in thier steam locomotives.  They use a magnet and plate system.   The small neodymium magnets are secured to the bottom of the frame.  thin sheet steel plates are put under the tracks.   Works pretty good.  Does not interfere with dcc either.    I will look it up tonight what the name and where to get.   

in the mean time,random thoughts,  could quartering be a problem?   The motor is just trying to turn slightly out of quarter wheels instead of that power going to the rail.  Or binding elsewhere like at the cylinder or maybe a rod is too long or short?  That all would rob ppwer. 

shane

A pessimist sees a dark tunnel

An optimist sees the light at the end of the tunnel

A realist sees a frieght train

An engineer sees three idiots standing on the tracks stairing blankly in space

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Posted by railandsail on Tuesday, November 30, 2021 7:39 AM

Lets stick with the 'pusher/helper' theme of this subject thread. I'm NOT suggesting that the tender drive itself have any drive shaft connection to the boiler unit. I'm simply saying to make that/those tenders heavy and powerful enough to push/pull our steam loco around the layout.

I experimented with that recently in just plain old DC mode. I used an Atlas S2 (die-cast frame, very heavy) to push my Backmann Northern around the layout. It did extremely well, and likely with a little tweaking could have done it with just as many cars WITHOUT the motor in the Northern.

If we could spend the same time to get all the visually detail stuff on the boilers of our steamers WITHOUT having to engineer the more complicated drive train in there, it would certainly be cheaper,...to design, and to produce.

And we could put a nice speaker system in that relatively 'empty' boiler shell to have fantastic sound coming from where it should. We could also likely improve the electrical pickup on those big drive wheels, spring them (as has been suggested), and send the improved electrical signal to our decoder in the boiler, then subsequently to the powerful tender.

 

 

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Posted by ATLANTIC CENTRAL on Tuesday, November 30, 2021 8:15 AM

railandsail

Lets stick with the 'pusher/helper' theme of this subject thread. I'm NOT suggesting that the tender drive itself have any drive shaft connection to the boiler unit. I'm simply saying to make that/those tenders heavy and powerful enough to push/pull our steam loco around the layout.

I experimented with that recently in just plain old DC mode. I used an Atlas S2 (die-cast frame, very heavy) to push my Backmann Northern around the layout. It did extremely well, and likely with a little tweaking could have done it with just as many cars WITHOUT the motor in the Northern.

If we could spend the same time to get all the visually detail stuff on the boilers of our steamers WITHOUT having to engineer the more complicated drive train in there, it would certainly be cheaper,...to design, and to produce.

And we could put a nice speaker system in that relatively 'empty' boiler shell to have fantastic sound coming from where it should. We could also likely improve the electrical pickup on those big drive wheels, spring them (as has been suggested), and send the improved electrical signal to our decoder in the boiler, then subsequently to the powerful tender.

 

 

 

I would still like to know which Bachmann Northern we are referring to, since they have made at least three completely different 4-8-4 models.

But in any case, as much as I am perceived as a Bachmann fan, none of their 4-8-4's have been great pullers out of the box. And there are lots of similar sized locos from Bachmann and others that pull dramaticly better.

So which loco are we talking about?

I only own the N&W J, and I consider it a project that needs weight, and maybe a new motor and gear ratio.

Sheldon

    

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Posted by ATLANTIC CENTRAL on Tuesday, November 30, 2021 8:37 AM

And, for what it is worth, I think a tender driven steam loco with a "diesel like" drive on the tender trucks could be a really good thing.

The biggest challenge will be to design those gear driven tender trucks so they still look correct. Some types would be easier than others.

Who has a million dollars to play with? I will help develope and market it.

Sheldon

    

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Posted by snjroy on Tuesday, November 30, 2021 9:54 AM

The NWSL Stanton drive could be used, I guess. These are two axle trucks though, so not really appropriate for a heavy tender. 

I'm not opposed to the idea of a tender drive, but I suspect that the pushing motion on the engine may cause derailments from the engine, especially longer locos. The proof will be in the pudding, as they say.

That being said, I don't see what problem we are trying to fix here. I think that the manufacturers have nailed it pretty well when it comes to the drive train under the boiler, at least Bachmann has on its recent products. I'm told that the new Civil War 4-4-0 is great with the new tooling, that now puts everything under that tiny boiler. They remain fragile, but so would a tender drive system as it does not remove the fragility of the side rods and valve linkages. And they still need to be quartered. 

Rapido's recent steam engines use a multi-wheel gear system under the boiler. It appears to be very powerful, but I would not want to take these apart for servicing. Servicing a tender drive, on the other hand, would be a cinch.

Simon

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Posted by Trainman440 on Tuesday, November 30, 2021 10:19 AM

Biggest problem with mid train pushers disguised as freight cars is attempting to get them speed matched with the engine.

I think designing a non-worm gear equipped gearbox would be super beneficial in this regard, as it can just spin freely if not powered, but also it can just give a pushing force without causing issues (locking gears) if not speed matched properly with the engine and/or other powered cars. 

Sort of like one of those coasting drive gearboxes, but not quite. (those simply disengage the worm from the worm gear.)

Think about the possibilties, we can finally get hump yards on flat track! :)

These arent even that hard to make themselves, Im sure darth could easily rig something up!

Charles

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Posted by ATLANTIC CENTRAL on Tuesday, November 30, 2021 12:31 PM

snjroy

The NWSL Stanton drive could be used, I guess. These are two axle trucks though, so not really appropriate for a heavy tender. 

I'm not opposed to the idea of a tender drive, but I suspect that the pushing motion on the engine may cause derailments from the engine, especially longer locos. The proof will be in the pudding, as they say.

That being said, I don't see what problem we are trying to fix here. I think that the manufacturers have nailed it pretty well when it comes to the drive train under the boiler, at least Bachmann has on its recent products. I'm told that the new Civil War 4-4-0 is great with the new tooling, that now puts everything under that tiny boiler. They remain fragile, but so would a tender drive system as it does not remove the fragility of the side rods and valve linkages. And they still need to be quartered. 

Rapido's recent steam engines use a multi-wheel gear system under the boiler. It appears to be very powerful, but I would not want to take these apart for servicing. Servicing a tender drive, on the other hand, would be a cinch.

Simon

 

The OP has steep grades and sharp curves, and wants big steam locos to pull  moderately long trains. As he notes, his diesels will but steam will not.

Interestingly, the mysterious Bachmann 4-8-4 he talks about is likely one of the worst pullers in the industry, unlike a number of other locos from Bachmann and others.

Sheldon

    

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Posted by RR_Mel on Tuesday, November 30, 2021 1:28 PM

I have a pair of Bowser 4-8-4 mechanisms with Bachmann GS4 shells that do pretty good, much better than the Bachmann.  The Bowser mechanisms come with additional weights.  I think all the Bachmann 4-8-4 shells will fit Bowser mechanisms.

EDIT:

A single Bowser/Bachmann GS4 will pull 13 Athearn over weighted passenger cars up my 3½% grades.

 
Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Turned 84 in July, aging is definitely not for wimps.


  • Member since
    December 2008
  • From: Heart of Georgia
  • 4,646 posts
Posted by Doughless on Tuesday, November 30, 2021 2:14 PM

I have no dog in this hunt for better pulling from steam locos, but with issues about layouts and equipment not performaing how we want them to, I level set the problem in my head by asking what would the prototype do to solve the problem.  Or what would they NOT do that created a problem that then had to be solved.

How would they build a loco to perform the work it needed to perform?  And, does the model do the same thing.

As OP noted, the ROCO designed Atlas S2/4 is an excellent puller.  Its also designed with low gearing.  It pulls alot of cars and runs slow, like a switcher is supposed to do. Duh.

A 0-4-0 docksider is supposed to shunt a few cars around sharp curves, mainly on flat grades.  Why expect a model to be different?  If the grades were steep, the prototype probably doubleheaded them (which would look cool, BTW).

A 4-6-2 is a passenger locomotive built mainly for speed.  It takes a while to get up to speed and probably conquers steepish grades partly by getting a good speedy run at it.  Are you trying to run it like a slow freight drag?

A 2-8-4 Berkshire was built for speed on flatlands.  Yes there were different variations, but again, a slow freight drag was not its forte.

8 drivers, 10 drivers were built for broad curves. 6 drivers for sharp curves.  A 6 drivered loco is small, and is not supposed to pull a lot of cars up steep grades by itself.   

Sure, if you want to change a locomotive so that it will do anything train related you wanted it to do, there are plenty of ways to build the one-off project.

TYCO's Chattanooga Choo Choo had the drive in the tender to have a smoke box in the engine, circa 1977.

You can have a permanent freight car behind a tender, very unprototypically, if you want to run the layout unprototypically.  Nothing wrong with that, but one decision sort of begets the other, which is what creates the problem.

 

- Douglas

  • Member since
    May 2021
  • 16 posts
Posted by dennis461 on Tuesday, November 30, 2021 6:36 PM

I do not see a problem...

  • Member since
    January 2009
  • From: Maryland
  • 11,263 posts
Posted by ATLANTIC CENTRAL on Tuesday, November 30, 2021 8:35 PM

Brian,

I would still be interested to know which Bachmann 4-8-4? Why is this such a secret?

And how steep are these grades? 3%? More?

Sheldon

 

    

  • Member since
    May 2014
  • From: Pennsylvania
  • 1,048 posts
Posted by Trainman440 on Tuesday, November 30, 2021 9:31 PM

To the OP: 

I think what youre comparing here is a bit unfair. 

Assuming you're using a Bachmann ATSF/NYC/SP 4-8-4 (which roughly all have a similar design), you're really not giving the 4-8-4 a fair shot. 

First off, these engines have 80" drivers, MUCH larger than the atlas S4 you're comparing it to. Designed for speed. 

Second off the gearing on these engines arent exactly designed with low speed, high torque in mind. 

Third off, Bachmann's engines are far from well tuned enough to operate with precision and balancing in mind. These are upgraded from engines designed all the way back in the 1980s...meant as cheap starter set locos. You're comparing this entry level engine designed with low budget in mind to some of the best diesel drives in the century. 

Lastly, your S4 diesel has diecast in its mechanism. Bachmann's 4-8-4s have a huge plastic shell, and lots of additional space inside for weight. More proof that these engines werent designed for the maximum possible pulling power in mind.

So you're going to use this ONE sample, comparing a low engine steamer to a well made diesel? And conclusively say that all modern built steam engines need to be improved?

I find it logical you took a cheap steamer originally first made in the 1980s and compared it to a "new" diesel and found it to be inferior. Also you openly admitted you compared a plastic engine to one with diecast yet was surprised your diecast engine performed better. 

If youre going to use a mid range atlas diesel with a diecast frame, I suggest you compare it to a mid range steamer with a diecast frame (or diecast boiler better yet). Maybe a T1 or H10 (both with some diecast) from BLI. If you were to use one of these engines (or as someone mentioned an old penn line diecast steamer), you'll realize how much better these midteir steamers perform against midteir diesels. 

My $0.02.

Charles

---------------------------------------------------------------------------------------------------------------

Modeling the Santa Fe & Pennsylvania in HO

Youtube Channel: https://www.youtube.com/channel/UCLb3FRqukolAtnD1khrb6lQ

  • Member since
    January 2009
  • 6,313 posts
Posted by RR_Mel on Tuesday, November 30, 2021 9:56 PM

Sheldon

I was able to set some locomotives on my layout and check their drawbar this evening.

I have a DCC Bachmann 4-8-4 SP GS4 purchased about 10 years ago, very little run time.  It has 4.3 ounces of drawbar.  My two Bowser GS4s (DC) have 5.7 & 5.9 ounces of drawbar.

I have several older Bachmann GS4s Plus (DC) and they have 3.3 ounces of drawbar.

 

My method of measurement.



My arthritis pain is off the charts but I thought I needed to check them for this topic.


Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Turned 84 in July, aging is definitely not for wimps.

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