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Bachmann USRA 4-8-2 questions

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Bachmann USRA 4-8-2 questions
Posted by Alex V. on Tuesday, December 23, 2008 12:23 PM

What is the minimum radius for the HO Bachmann USRA 4-8-2?  What's the drawbar pull?

 

Thanks

Alex - Engineer, brakeman, conductor, hostler, railfan, railroad historian, and model railroader
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Posted by DigitalGriffin on Tuesday, December 23, 2008 12:27 PM

R18 is the mininum.

There's a consistant problem with the cow catch being way too low to the track.  It often catches grade changes and points on turnouts.  It's metal on the frame, so you'll need a Dremel or file to shave it down. 

The power pickup brushes up against the back of the wheels are questionable, and often out of alignment.  A little tweeking will be necessary.  Be careful you don't tweek the pickup into a driver spoke or it could rip off.  (Ask me how I know)

I also have one where the lead trucks wheels were out of gauge and another where the flanges had burrs. 

The motor drive gear is made of plastic.  I don't think it's Delrin, so LUBE IT OFTEN.

My George Washington Heavy Mountain 4-8-2 can haul about 8 Pullmans up a 2% grade.  Any more and you risk wheel slippage.

 

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

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Posted by Alex V. on Tuesday, December 23, 2008 12:47 PM

Thanks for the review and tips.  FWIW I just recieved an undec. version of this loco for an early Christmas present.

The only trackage I have right now is a 4x6 Christmas layout - min. rad. of about 20", with about a 3.5% grade.  Mischief  Needless to say, I'll be building a bigger layout soon! 

 

 

 Thanks.

Alex - Engineer, brakeman, conductor, hostler, railfan, railroad historian, and model railroader
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Posted by stokesda on Tuesday, December 23, 2008 4:09 PM

I have a slightly older Bachmann Spectrum 4-8-2 heavy (DCC ready, no pre-installed decoder), and it performs fairly well. It negotiates my 22" curves just fine, so I don't think you'll have any problem with 20". My only complaint is I felt it was a fairly light puller. I had it over at a friend's house one day trying to climb a steep incline, and it kept slipping about halfway up. I found if I pushed down a little on the sand dome with my finger, it would keep going. So I think it may be a little underweighted. My friend's Spectrum 2-8-0 climbed the same hill with a longer consist and didn't slip once. I don't know how steep the incline was, but I'd guess it's in the neighborhood of your 3.5%.

Just be aware of that. If yours starts slipping, lightly press down on the top of the engine and see if it will gain traction and keep going. One of these days I'll take it apart and see if there's any way to stuff some extra weight inside.

Dan Stokes

My other car is a tunnel motor

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Posted by DigitalGriffin on Tuesday, December 23, 2008 4:32 PM

stokesda
One of these days I'll take it apart and see if there's any way to stuff some extra weight inside.

It's a bit of a bear to get the boiler back on.  Whatever you do, don't try to force it down at the rear!  Push the steam chest (front end) down firmly then pull towards the back.  It should slide back enough that the rear plate should slide over the frame.

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

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Posted by wjstix on Tuesday, December 23, 2008 4:43 PM

You didn't mention which one you have...the USRA light Mountain has a plastic boiler, the USRA heavy has a die-cast metal one which increases it's pulling power considerably. My light 4-8-2 is a great runner but I use it primarily on 5-6 car passenger trains so it's not required to do any heavy lifting. Smile

Stix
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Posted by twhite on Tuesday, December 23, 2008 7:35 PM

I've got one of the Spectrum Heavy 4-8-2's, it came with a Southern Pacific tender, so I kit-bashed it to resemble one of the SP MT-series (without the 'skylilne' casing, of course).  It does have room in the cast metal boiler for additional weight, though I've found that the loco as straight from the box is a pretty decent puller.  I use mine primarily for freight (the MT's were true dual-service locos), and it can handle a fairly good-sized train up my 2% grades with very little trouble.   As to minimum radius, mine is a 34", so it will handle just about any steamer.  However, with the 4-wheel leading truck and the overhang on the cab, I would think that 22" would be just about a minimum radius for this loco.  If you're going to add weight, my suggestion would be to add it just under, or forward of, the steam dome, making sure that the weight is insulated from the split frame. 

It's a nice lokie.  I sure like mine.  It's not as 'heavy' a puller as my three brass MT 4-8-2's, but it does the jobs that I assign it without any problems. 

Tom Smile 

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Posted by Alex V. on Tuesday, December 23, 2008 9:07 PM

Thanks for all the reviews, guys.  The more I run and look at this engine, the more I like it!

One small problem - there seems to be a roughness, or drag, while going forward - enough to make the engine lurch at low speed and make an audible noise.  It's right as the fireman's side main rods come up to the top - the wheels slow down until they've passed TDC and some noise can be heard as they do that.  Any idea what this is?

I took the bottom plate off and greased the main drive gear on the 3rd axle with white grease, and in doing that I did move the driven gear on the driving gear almost a whole revoution - could this be part of the problem?  Are there other gears up in there that are dragging, that I need to lube?  Thanks.

Alex - Engineer, brakeman, conductor, hostler, railfan, railroad historian, and model railroader
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Posted by twhite on Wednesday, December 24, 2008 11:59 AM

Alex--

Does that audible noise when the drivers slow down also involve a 'clicking' sound?  If so, you might have disturbed one or more of the small bronze pickups on the inside of the drivers.  If they're accidentally bent (and they are VERY thin), they'll rub against the spokes and 'click'.  I had that happen to mine, it was just a matter of gently flattening them out against the inside of the drivers. 

Just a thought.

Tom Smile 

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Posted by Alex V. on Wednesday, December 24, 2008 1:32 PM

Tom - no, it's not one of the pickup pieces.  One WAS bent down (to where it caught on switches and such) but I straightened it out and now it's fine.  There is a slight clicking, but it's more muffled and sounds like it's inside the engine (in the gear train), not down where the contacts are.

Would the hesitation be because of the belt on the belt drive?  I didn't think this had the belt drive, but looking in the parts blowup confirmed that it did.  My Spectrum 2-10-0 also has belt drive and it acts a little like this, but nowhere near this bad.  Confused  BUT, if it was stiffness in the belt, would the "rub" be in time with the wheels, or in time with the belt pulleys or some other part?  Is the output shaft for the belt geared 1:1 with the wheels?

Alex - Engineer, brakeman, conductor, hostler, railfan, railroad historian, and model railroader
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Posted by rockymidlandrr on Wednesday, December 24, 2008 7:14 PM

My URSA Heavy Mountain has been able to handle 18 radius curves, but it really doesnt like them.  Thanks goodness the 18 radius is on a branch.  Mine handles a decent load behind it, but anything over 10 or so cars the motor starts to whine just a little bit.  Is that what your hearing?

Still building the Rocky Midland RR Through, Over, and Around the Rockies
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Posted by twhite on Thursday, December 25, 2008 1:01 PM

Alex--

If the drag is occuring at the same place all of the time, it also might be a tight rod problem.  You might want to lube your main and eccentric rods with just a drop of very light oil (LaBelle makes a very light plastic-compatable oil for this) and see if that improves the 'lurch'.  Also the point where the main rod goes into the cylinders.  Sometimes a very light lubing can clear up that kind of problem.  I lube my steamers just as a matter of course when I buy them. 

Tom

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Posted by Alex V. on Thursday, December 25, 2008 2:01 PM

  I usually lube mine pretty soon after I get them, too - just to be on the safe side.

  Last night, I took the bottom cover off again.  Pumped a fair amount of grease down in the worm gear cavity, and put some more in the teeth of the gear on the 3rd axle.  I also rotated the drivers - without running the motor - and it seems to have cleared up a lot of the problem.  There are still a few smaller sticky spots per revolution, but nowhere near as bad as the one spot before. 

  The motor and gears seem to make a lot more noise going forward than backward - any ideas why?

 Thanks.

Alex - Engineer, brakeman, conductor, hostler, railfan, railroad historian, and model railroader
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Posted by wjstix on Thursday, December 25, 2008 3:19 PM

One of my Spectrum engines had the siderods slightly bent inwards, probably from being in the packaging, so it displayed the 'hesitation' you're talking about. Carefully looking over the rods and finding the bent on and gently bending it back out slightly did the trick.

Stix
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Posted by IC_Tom on Monday, June 13, 2022 5:25 PM

twhite

Alex--

Does that audible noise when the drivers slow down also involve a 'clicking' sound?  If so, you might have disturbed one or more of the small bronze pickups on the inside of the drivers.  If they're accidentally bent (and they are VERY thin), they'll rub against the spokes and 'click'.  I had that happen to mine, it was just a matter of gently flattening them out against the inside of the drivers. 

Just a thought.

Tom Smile 

 

Yes, it's been forever with this thread.  If anyone is still paying attention, though, I just wanted to say, "Thanks!"

I snagged a couple of Spectrum Heavy Mountains in my beloved ICRR from ebay over the past year.  I finally got some time to install an inexpensive Soundtraxx mobile-only decoder in one over the last few days.

It ran horribly.  The motor was noisy, it clicked all the time, and jerked.  I found a post referencing the TCS mobile decoder upgrade for the Bachmann Heavy Mountain.  It mentioned clipping the leads of the two capacitors on the Bachmann mother board.  I did that, and things improved considerably, but that clicking sound continued.

I searched all over the net for solutions this morning and found this post.  Sure enough, inspecting my Mountain revealed two of the pickups were swallowed up by the wheel spokes.  I removed the base keeper plate, bent the pickups back into shape, and voila!  The clicking noise is gone and it runs (and crawls) like a champ.

Thanks again!

P.S. Maybe some of you remember this, but it brought back memories of when I was a kid and used clothes pins to attach playing cards to my bicycle so that the wheel spokes would hit the cards.  In that case, I wanted the noise.

Better to use a sound decoder and speaker to make noise with an HO loco. Wink  That'll come next, now that I know my Mountains are keepers.

 

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Posted by doctorwayne on Wednesday, June 15, 2022 8:57 PM

Thanks to the glitches on this site, I've just wasted over five hours trying to submit weights and drawbar ratings for a number of my layout's steam locomotives, including Bachmann's Light 4-8-2...all gone in a few seconds.

Not one to be deterred by bad technology, I'm gonna give it another shot.

All of my steam locomotives have added weight, both in the loco and tender, which also includes loose coke breeze (fine material from the making of coal into coke for the steel industry) as coal in the tenders.

The poorest puller on my layout is a Proto 0-8-0, heavily modified to represent a CNR prototype...

It weighs-in, loco and loaded tender, at 17.8 oz., with a drawbar pull of 1.9 oz., which is sufficient for moving at least 20 cars on level track.

This Bachmann Ten Wheeler, one of two, originally looked like this...

...but I modified them, using Varney cast metal boilers and plastic Bachmann cabs from Bachmann Consolidations...

The total weight of one, including the loaded tender, was 18.8 oz.,with a drawbar pull of 2.1 oz.  Despite the greater drawbar pull, it struggled with 20 cars once it entered a curve.  I normally run these two 10 Wheelers together, as much of the layout is on grades, which often include curves - minimum radius is 30", and only in one place.  Everywhere else, the radii are 32" and wider, some up to 48".

Next up is the Athearn Genesis Light Mikado, one of 6 (four are currently in service)...

...weighing 24.8 oz., and a drawbar pull of 2.8 oz.

Surprisingly similar to the Genesis Mikes for pulling is this brass 10 Wheeler...

...which is a little lighter (21.3 oz.), but also has a drawbar pull of 2.8 oz.  I have a second one under construction.

This IHC Mogul was bought some years ago...

...its oil tender modified for coal, and a new cab from a Bachmann Consolidation.  I replaced the original motor and added extra weight.  It weighs-in at 16.9 oz., with a drawbar pull of 3.1 oz.

Usually operating with the 37 is this brass Mogul, my first brass loco.  I've modified it several times from its original look, from this...

...to this...

I've re-geared and re-motored it, along with the extra weight  and modifications.  It weighs-in at 19.7 oz., with a drawbar pull of 3.3 oz.

This Bachmann Consolidation, one of eight (five are in-service)...

has added weight, and tips the scale at 22.5 oz., with a drawbar pull of 5.9 oz.

That brings us to the Bachmann Light Mountain...

...which weighs-in at 25 oz., but a drawbar pull of only 3.5 oz.

This brass 0-6-0 was given to me by a friend, who felt that it didn't pull well enough for his needs...

...I added weight, and replaced the old magnets in the open-frame motor using rare earth magnets, then gave it a paint job and some CNR lettering.
I did offer it back to my friend, but he declined, as he had found two very heavy brass 0-8-0s, which I later painted for him.

The 0-6-0 weighs in at 20.9 oz., with a drawbar pull of 3.8 oz. - good enough to handle 20 cars on level track.

I bought this Bowser Pacific for my son, but he lost interest in model railroading fairly early...

 

While I did modify it, I plan on changing it into a copy of one of my hometown Pacifics operated by the TH&B.
Its current weight is 32 oz., with a drawbar pull of 4.4 oz.

Surprisingly, even to me, the top dog for pulling power was my kitbashed "BEE", a Rivarossi Santa Fe combine that I hacked-up and rebuilt using part of the frame from an Athearn F-unit, along with a motor and lots of weight...

Perhaps I shouldn't have included it with steam locos, but it does fit into the steam era.  It weighs-in at only 20.6 oz., but has a drawbar pull of 7.5 oz.

I have had diesels that weighed considerably more and had higher drawbar ratings, too, but they were definitely from a more modern era.

I should also include a mention that photobucket contributed to the lengthy posting procedure, with their slow-paced loading of the required images.

Wayne

 

 

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