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4-8-4 Engines slipping on 2% grade on new layout build

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4-8-4 Engines slipping on 2% grade on new layout build
Posted by Redhawk95 on Tuesday, October 18, 2022 8:06 AM

Hello everyone, I am currently in the process of building a new multi deck layout and I just completed the first continuous loop on the bottom deck. The layout is a folding dog bone with a a 2% grade and 30" inside and 32" outside curve radius on one side. I have a Bachmann 4-8-4 and a MTH 4-8-4 that I am trying to pull a 5 car passenger train with and both locos slip and struggle to make it up this grade. It does not seem like these engines should be struggling with such a small load. Does anybody think this is normal? Should I look into weighing the engines down? 

I have a Broadway Limited Y6B that can pull a 16 car freight train around this loop like there aint nothing to it. So I feel like its not a track problem. Any suggestions would be greatly appreciated because I had visions for pulling 11 car passenger trains around this layout. Thank you 

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Posted by NVSRR on Tuesday, October 18, 2022 9:06 AM

Locomotive weight is the first thing that comes to mind.  Too light for the grade and weight pull.    First I would look at.

how old is that Bachman? 

 

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 wjstix on Tuesday, October 18, 2022 9:52 AM

An engine's pulling power can be affected by a grade and by a curve, so having a 2% grade on a curve may affect an engine more than a 2% grade on straight track would.

As Shane mentions, which Bachmann engine you have and how old it is could be a factor. With a few exceptions (USRA 2-10-2 and Heavy 4-8-2) Bachmann engines have plastic boilers so don't have much weight, which can cause slippage. Also, older versions of say their NYC Niagara had relatively poor motors so didn't have much pulling power. 

You don't say which MTH engine you have, but there too, if it has a plastic boiler it could be causing the slippage.

Make sure too that all the wheels are firmly on the rails. Many Bachmann engines have an apron that swings down from the back of the cab to sit on the 'lip' at the front of the tender. If the apron gets under that lip, it can lift up the engine slightly, making the drivers not fully reach the track. I try to tip the apron all the way up, get the engine's wheels all on the track, then reach in with a screwdriver or pencil and lower the apron.

Stix
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Posted by Water Level Route on Tuesday, October 18, 2022 11:53 AM

Take a good hard look at how free rolling those cars are too.  I have a BLI Niagara without traction tires that pulls a 5 car consist of walther's Proto 85' passenger cars up a 3-1/2% grade that is the full length of a 25" radius curve.  I have a Bachmann light 4-8-2 that could pull any combination of freight cars up to a certain length up the same grade, unless I had one particular caboose coupled on the end.  That one caboose rolled so poorly it cut train length up the grade in half!  I never knew it on the flat layouts I had prior.

Mike

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Posted by Redhawk95 on Tuesday, October 18, 2022 12:04 PM

Both the Bachman and the MTH locomotive were bought last year. 

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Posted by Redhawk95 on Tuesday, October 18, 2022 12:11 PM

The Bachmann is last years version of the J class 4-8-4 611 and the MTH loco I also bought last year and is the J class 4-8-4 603 I bought new. I am pretty sure the Bachman is a plastic boiler but the MTH feels like metal. 

So would you suggest getting tungsten putty and start adding weight to the inside of the engines? How much weight would you start off with? 

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Posted by doctorwayne on Tuesday, October 18, 2022 3:09 PM

This much modified Bachmann locomotive...

...was never a good puller, and eventually quit running.  The tender was a partial scratchbuild, using part of a sun-damaged covered hopper that I converted into a centipede-type.
I sold it, quite cheaply, to a friend...he was aware that it didn't run, but it was a fairly nice loco for photographic purposes.

Pretty-well all of my locomotives get added weight...

I re-built three of these Athearn U-boats....

...fitting them with two motors each, and filling the bodyshells with sheet and custom-cast lead weights...

Each of them weighed in at just over 33 oz., and all three had similar drawbar pull-capacities of 8.3 oz.  They easily pulled a 22 lb. train of hoppers, filled with Black Beauty blasting medium, up a 45' long 2.8% grade, composed of two complete horseshoe-type curves (one to the right, and one to the left), followed by a series of wide radius S-bends.

I add weight to all of my locomotives, diesel or steam, and usually as much as can be crammed-in.

Most of the added weight is lead, cast in homemade aluminum moulds.

Here's an Athearn Genesis Mikado, one of six modified with extra weight...

...the air tanks are brass tubing, also filled with lead, and the cab has sheet lead under the roof, and lead seat's for the fireman and engineer.  The tender was modified by removing the coal bunker's cast-plastic load and fashioning a suitable coal bunker to allow use of either Black Beauty blasting medium or coke breeze as the fuel load.  The tender's cistern was also filled with blocks of lead, and all of the tenders' wheels were fitted with wipers to increase electrical contact.

In completed form, the engine/tender combo weighs-in at just over 25 oz.

Wayne

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Posted by "JaBear" on Tuesday, October 18, 2022 4:19 PM
I can’t recollect how much extra weight I added to this locomotive, using a form of doctorwaynes method, but would suggest that as you add the extra weight, try and get the locomotives weight balanced over the centre of the drivers.
 
Balance by Bear, on Flickr
 
Out of curiosity I just weighed the engine and tender, the result is 24 oz.
My 2 Cents Cheers, the Bear.Smile

"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."

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Posted by York1 on Tuesday, October 18, 2022 4:31 PM

I guess I'm wondering if it is slipping.

If so, I'd wipe the rails with rubbing alcohol and clean the locomotive's wheels with alcohol.

I don't know if that will make a difference, but it is the easiest thing to try before you get to more complicated stuff.

York1 John       

I asked my doctor if I gave up delicious food and all alcohol, would I live longer?  He said, "No, but it will seem longer."

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Posted by gregc on Tuesday, October 18, 2022 5:36 PM

i'm curious.   could you post the weight of the loco and passenger cars (total) and how easily the passenger cars rolls down the 2% grade?

greg - Philadelphia & Reading / Reading

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Posted by dknelson on Tuesday, October 18, 2022 5:49 PM

Another factor that is familiar to buyers of smaller brass locomotives and that is that the driver treads are really slick when new and over time and with enough running that should ease.  Don't rub the driver treads with abrasive as that is an invite to places that gather dirt.  

It should probably also be mentioned that while 2% grades are rather common on layouts, on the prototype a 2% ruling grade is something to be reckoned with.

Dave Nelson

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Posted by MisterBeasley on Tuesday, October 18, 2022 5:52 PM

I have a Bachmann light Mikado that couldn't pull a dozen freight cars around my basically flat layout.  I swapped out all the old plastic wheelsets and it so imprived rolling performance that i just kept goilg until all my wheels were metal.

It takes an iron man to play with a toy iron horse. 

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Posted by Redhawk95 on Tuesday, October 18, 2022 6:49 PM

unfortunately I do not have a scale at the moment. I can tell you that if you u couple the passenger cars at the top of the grade they will run very fast down the grade and well past the end of the grade about 4 feet into a staging yard.

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Posted by Redhawk95 on Tuesday, October 18, 2022 6:52 PM

I notice a lot of you guys using lead. Has anyone ever used tungsten putty? It's heavier and moldable just seems like a better substitut. Just wondering if there is a reason. 

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Posted by "JaBear" on Tuesday, October 18, 2022 7:13 PM

Redhawk95
I notice a lot of you guys using lead...   ... Just wondering if there is a reason.

The only reason I use lead, that I have a reasonable amount that I got for FREE!  I also have the wherewithal to make moulds to make the weights.
Cheers, the Bear.Smile

"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."

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Posted by Pruitt on Tuesday, October 18, 2022 8:16 PM

One sure-fire fix - add Bullfrog Snot to the rear set of drivers on each loco. It acts like a traction tire. Works great!

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Posted by wrench567 on Tuesday, October 18, 2022 10:39 PM

Redhawk95

I notice a lot of you guys using lead. Has anyone ever used tungsten putty? It's heavier and moldable just seems like a better substitut. Just wondering if there is a reason. 

 

  Cost. I have a bunch of lead flashing. It was free. It's maleable and easy to work.

How much weight do I add to my locomotives? As much as I can fit. Some of my brass locomotives had cast zink weights. They were replaced with lead. You can find places if you think outside the box. Cab roofs, cab floors, smoke box, and fire box are some places. I even put lead inside the cylinders just leaving room for the piston rods.

    Pete.

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Posted by doctorwayne on Wednesday, October 19, 2022 1:51 AM

I got sheet lead from a small company in my hometown of Hamilton, Ontario, and dropped in to buy some.  I don't recall how much I had intended to buy, but the two guys running the melting pot simply cut off 5' or 6' of it and wished me a good day...no charge. 

I also dropped by a tire shop a couple miles from home, and asked if they had any scrap wheel-balancing weights available.  I got about 10lbs. of them, although some turned out to be steel or zinc.

I have lots of sheet aluminum on hand, from when we bought the house next door to ours.  It's perfect for creating moulds if you wish to cast your own  for adding weight to both locomotives and rolling stock.  A straight-edge, a knife, and tin-snips will do the job

Here are some pictures ...

I made a melting pot, using the steel cap from a spray-bomb, along with a piece of broomstick, then loaded some lead into the pot, put it on the vice and then heated it with a propane torch...

After the lead has been poured into the moulds, it takes only a few minutes to harden, but I do let it cool before removing the castings from the moulds...

The moulds can be used several times, but eventually the aluminum will fatigue.

These simple moulds were used to make the boiler weights for the Genesis Mikados....

Bear's comment about balancing the weight at the mid-point of the loco's wheel base is good advice for getting the best results when adding extra weight.

Wayne

 

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Posted by BEAUSABRE on Wednesday, October 19, 2022 4:09 AM

You might want to consider replacing the trucks and wheel sets of your cars and/or using MicroMark's Truck Tunner and Truck Spreader on the journals and trucks Search results for "truck tuner" (micromark.com)

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Posted by gregc on Wednesday, October 19, 2022 5:43 AM

BEAUSABRE
You might want to consider replacing the trucks and wheel sets of your cars

doesn't seem warranted, yet.  he said the cars roll freely

Redhawk95
I can tell you that if you u couple the passenger cars at the top of the grade they will run very fast down the grade and well past the end of the grade about 4 feet into a staging yard.

i think adding weight is where to start, but not sure without knowing weight of loco or cars

greg - Philadelphia & Reading / Reading

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Posted by Water Level Route on Wednesday, October 19, 2022 6:08 AM

Pruitt

One sure-fire fix - add Bullfrog Snot to the rear set of drivers on each loco. It acts like a traction tire. Works great!

 

Amen to that!

Mike

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Posted by selector on Wednesday, October 19, 2022 3:04 PM

Lots of savvy and highly experienced responders above.  I will add that undulating track and grades-that-are-steeper-than-we-think are often going to trip up the intrepid layout builder.  My BLI Niagara can brute six Walthers Heavyweight passenger cars, plus two head-end reefers, up my 3% grades, and that's the Paragon from 2004/5 with no traction tires.

I do lube my cars' trucks, though, with plastics compatible ATF.

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Posted by Redhawk95 on Wednesday, October 19, 2022 6:05 PM

So I did just weigh the MTH engine. It is 23 ounces without the tender and 37 ounces with the tender on it combined. So that's only 1 oz less than your engine. so do you guys still think its a weight issue? 

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Posted by Redhawk95 on Wednesday, October 19, 2022 7:07 PM

Also I would like to add that I have a BLI n&w Y6B that I tried pulling the longest possible train that I could around this grade and it was able to pull 16 coal cars as well as 6 passenger cars. But these 4-8-4s are struggling to pull anything more than 4 passenger cars. I just put an order in for some tungsten putty so I'm hoping to see a change. I mean its super frustrating to see that. Haha 

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Posted by wrench567 on Wednesday, October 19, 2022 7:50 PM

  Beside adding weight, try removing the springs on the front and trailing trucks. That would put more weight on the drivers. Sometimes those springs do more harm than good.

     Pete.

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Posted by gregc on Wednesday, October 19, 2022 7:55 PM

Redhawk95
It is 23 ounces without the tender

what do the passenger cars?  i'm curious about the y6b

i'd estimate that the engine can pull (tractive effort) 5oz. (20-25% of weight on drivers)

better rolling cars require < 2% of their weigh to move on level track.  add 2% for the grade and possibly another 1% (R/30) for a curve and that's ~5% or ~100 oz (weight of train)

less 14 for the tender leaves ~86oz

do your 5 passenger cars weigh about ~17 oz/car?

greg - Philadelphia & Reading / Reading

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Posted by wjstix on Thursday, October 20, 2022 2:39 PM

wrench567

  Beside adding weight, try removing the springs on the front and trailing trucks. That would put more weight on the drivers. Sometimes those springs do more harm than good.

     Pete.

 

 
That's a good point, I had a 4-4-2 that pulled poorly and slipped a lot. Turned out the springs (particularly on the front truck) were so strong that the drivers were barely touching the track. Removing them greatly increased pulling power. 
 
Also might want to check the tender - sometimes depending on how the power wipers on the tender trucks are set up, they can cause quite a bit of drag.
Stix
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Posted by maxman on Thursday, October 20, 2022 11:05 PM

Redhawk95

So I did just weigh the MTH engine. It is 23 ounces without the tender and 37 ounces with the tender on it combined. So that's only 1 oz less than your engine. so do you guys still think its a weight issue? 

Weight of the tender is not relavent to pulling ability since that weight is not over the drivers.

However, the tender weight will work against you as it increases the load the engine has to pull.

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Posted by Redhawk95 on Sunday, October 23, 2022 9:26 PM

So my tungaten weight came in the mail today. Ended up adding a little less than 4 oz and removed the rear spring for the guide wheels. Now the train has zero struggle at all up the grade. Now sure if it was the spring that helped the most or the weight. Just doesn't seem like 3.5 oz would make that much of a difference. I may go ahead and remove the front spring as well just to see how it does. 

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Posted by "JaBear" on Monday, October 24, 2022 12:57 AM
Well, it’s good to see you’ve had a win, even if you’ve used the shot gun approach to trouble shooting!Smile, Wink & Grin
Cheers, the Bear.Smile

"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."

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