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NMRA car weight

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Posted by maxman on Friday, April 3, 2015 11:09 AM

TomLutman
So the extra weight helps with stringlining and derails, but is there any other benefit the extra weight brings to the table?

The addition of a little weight to bring it up to the NMRA recommended practice helps with car coupling.  With the free-rolling wheels now available on some cars, and the ability of locos to creep up to the coupling point, you can end up chasing a car all over the railroad before overcoming any resistance to the knuckle opening.  Of course if you are one who likes to couple at 10 smph, then it doesn't matter.

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Posted by dknelson on Friday, April 3, 2015 10:56 AM

mactier_hogger

I'm with Mike Confalone on this one. Triple, or even quadruple the NMRA weights on cars so that our newer, efficient, model engines will have to work for a living! In other words, actually have to double the hill instead of pretending to do so.

 

 
An interesting thought and concept. I would only point out that one consequence of working our model engines really hard is that they will in fact wear out faster, and this comes at a time when it is my general impression that some of the really beautiful and pricey locomotives do not seem all that durable.  
 
The advent of free-rolling trucks around 1960 meant that model locomotives had a much longer service life, which is why some old Athearn and Mantua stuff is still going strong, for those who care to run it.  
 
Dave Nelson     
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Posted by mactier_hogger on Thursday, April 2, 2015 7:30 PM

I'm with Mike Confalone on this one. Triple, or even quadruple the NMRA weights on cars so that our newer, efficient, model engines will have to work for a living! In other words, actually have to double the hill instead of pretending to do so.

Dean

30 years 1:1 Canadian Pacific.....now switching in HOSmile

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Posted by TomLutman on Thursday, April 2, 2015 7:15 PM

So the extra weight helps with stringlining and derails, but is there any other benefit the extra weight brings to the table?

  The only derails I get is the occassional pilot truck climbing points, and I will work on tht later. The only thing I have going is some jerky action of the cars coming down a 1% grade and around a 24r curve, and thats happening as they exit the curve into flatground as couplers go slack and then get pushed into the next car.

  If bringing the cars from 2.5oz ish to 4oz will eliminate this, then it's worth me doing it. I've got lots of 158 and 240gr lead weights, but some of the cars can be interesting to get opened up.

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Posted by BRAKIE on Thursday, April 2, 2015 5:17 PM

Guys, The cars I have in mind is the modern cars like coil cars,60' cars,72' cars,automax,well cars,89 footers etc.

The measurement in inches varies greatly between cars and I fully believe they should have the same weight.

As a example compare a 89' auto parts boxcar next to a 50' boxcar next to a 64' reefer next to a 65' gon..Those cars is seen in every mixed freight train including occasional set of well cars.

Larry

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Posted by ricktrains4824 on Thursday, April 2, 2015 4:01 PM

Right.

I've found that the weight in of itself is not an issue, it's the having cars mixed in that have varied amounts of weight that causes the biggest issues. If all the cars are lightweights, or midweights (what I count for recommended), or heavyweights, you get less stringlining and, save for locomotive pulling power being affected, no ill effects from any of them. So, it's not a "must have it here, nowhere else" standard like wheelsets gauge, etc..., but, having some kind of minimum weight for the size is good, along with a (preferably) no heavier than this weight. Striving to be in the middle is good, and, my middle just happens to follow RP weights. Yes, I allow some "wiggle room" in it, because it's hard to have some of them exact, but try to stay as close as possible within that "wiggle room" middle of the RP weight. 

Ricky W.

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Posted by mlehman on Thursday, April 2, 2015 12:32 PM

dstarr
You want all the cars in a train to weigh about the same, with some allowances for longer and shorter cars.

What David said works for me.

With standard gauge, I do tend to follow NMRA RP weight when a car has issues that might be weigght related and no obvious defect stands out on inspection. Too heavy or too light will cause issues.

Like many narrowgaugers, I intentionaly underweight cars, but do it consistently. You'll find that Blackstone cars are a little light and that's because of consultation with the NG community. We like grades and straining small engines, so are cautious about added weight. It really cuts into the rated tonnage one can move. Yet the trains run well if track and rolling stock are in good order. That's what counts and why it's an RP not a Standard.

 

Mike Lehman

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Posted by NP2626 on Thursday, April 2, 2015 12:12 PM

It's my opinion is that RP20.1 works.  I'm sure the NMRA feels the same way.  It's a Recmmended Practice, that means it is only recommended, not required.  It is certainly not important to follow RP20.1 and if you have a better way, by all means do it your way.  I think if the NMRA felt it was time for a change, there would a hue and cry from the model railroading public, all thinking their way was a far better way to do things than some dumb committee would come up with, so, why change it?  

NP 2626 "Northern Pacific, really terrific"

Northern Pacific Railway Historical Association:  http://www.nprha.org/

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Posted by BRAKIE on Thursday, April 2, 2015 11:33 AM

dknelson
Some guys feel that the NMRA weight standards ceased to make sense with very long freight cars, but the NMRA standards were set when passenger cars were long, so one has to assume that the technical committee was indeed thinking of 85 foot cars.

Passenger cars is not a freight train of mixed freight cars of various lengths in one train.

No way did that committee of 50 plus years ago think about today's freight cars.How could they when freight cars was 40-50'?

The method that RP20.1 uses should be revamp and rethought but,this will never happen.

Larry

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Posted by jrbernier on Thursday, April 2, 2015 11:23 AM

  I am in the NMRA 'Sliding Scale' weight side of this discussion.  A lot of folks clain that the old metric is 'outdated' - I am of the opinion that they are just too lazy to do the work!  I try to get all of my cars up to the suggested weight.  Many times flat cars and open hoppers can be a challenge.  As Dave mentioned, getting a consistent weighting scheme is the key.  And good wheels/couplers/track are just as important.  I find that the 'heft' of a properly weighted car is really nice when switching.

  I ran a 'test' at the club last year.  I took my weighted cars with I-M wheel sets down to the club and ran them against 'factory' wieghted cars(current Athearn/Exactrail/Walthers/etc) cars.  My cars did weigh more on average, but I could pull more of my cars up the 2%, 33" radius curves that the 'lighter' cars.  I ream out the truck side frames with a Micro-Mark 'Truck Tuner' and install I-M metal wheels - They roll much better - even though they weigh more!

Jim

Modeling BNSF  and Milwaukee Road in SW Wisconsin

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Posted by ricktrains4824 on Thursday, April 2, 2015 11:10 AM

dknelson

The old Athearn Blue Box quad hopper was fairly notorious for derailing on curves due not to its weight but some design anomoly that could only be cured with more weight above the NMRA standard

Dave,

How did you know which coal hoppers I had loaded with live loads to add weight?!? Are you spying on me somehow? Indifferent

(Sorry, I Had to say it... Laugh)

Yes, added weight in those helped out tremendously... And they now track beautifully. Big Smile

Ricky W.

HO scale Proto-freelancer.

My Railroad rules:

1: It's my railroad, my rules.

2: It's for having fun and enjoyment.

3: Any objections, consult above rules.

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Posted by dknelson on Thursday, April 2, 2015 10:47 AM

There is nothing magically "right" about the NMRA weighting standards, but what is useful is to have a consistent standard for weighting on a layout, and the NMRA standards mean that you can exchange or purchase cars weighted to those standards and not have to tinker with them or accept the consequences of irregular weighting.

And of course not all weight is created equal - the lower the better.  And consistent weighting but inconsistent rolling qualities of the trucks, or mixing truck mounted and body mounted couplers, all create their own issues.

Certainly some variance in weight is usually OK and does not result in problems.  It is rare for any empty flatcars or gons to meet standards, but what weight they do have is low.  By contrast the old Varney ore car was light as a feather and was not easy to run in mixed freight trains -- and very difficult to run with the Model Die Casting all metal ore car which some of us remember.

It is also true that certain cars, due to their design or whatever, seem to have tracking problems unless weighted above the standards.  The old Athearn Blue Box quad hopper was fairly notorious for derailing on curves due not to its weight but some design anomoly that could only be cured with more weight above the NMRA standard  I think the blue box 60 foot tank cars likewise benefit from the somewhat heavier weights that Adair Shops offer.

Some guys feel that the NMRA weight standards ceased to make sense with very long freight cars, but the NMRA standards were set when passenger cars were long, so one has to assume that the technical committee was indeed thinking of 85 foot cars.  Indeed it was not an easy matter to make one of the old Walthers full length passenger car kits keep within NMRA standards if you decided to install a full interior with those old cast lead seats and figures - not to mention the underbody details.

Dave Nelson

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Posted by BRAKIE on Thursday, April 2, 2015 10:30 AM

dstarr
You want all the cars in a train to weigh about the same, with some allowances for longer and shorter cars.

This is especially true for those of us that run modern cars that can be 42-89' in lenght..I favor one weight for all cars to even the balance instead of RP20.1 method of weighing cars.

Of course most home layout trains is 10-30 cars so,there shouldn't be much of a issue.

Tommy Overspeed* may play a hand in derailments as well.

 

*Tommy Overspeed is/was a moniker for a engineer well known for pushing just above the track speed limits and just below the overspeed alarm.

 

Larry

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Summerset Ry.


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Posted by dstarr on Thursday, April 2, 2015 8:54 AM

You will find that pretty much all commercial rolling stock is underweight. You want all the cars in a train to weigh about the same, with some allowances for longer and shorter cars.  If you have some heavy cars and some light cars in the same train, the heavy cars tend to pull the light cars off the track on curves (stringlining).  So you want to have some kinda weight standard for your road, either your own standard or someone else's. Many of us use the NMRA standard even though it has been criticzed as being overly heavy. 

I do remember my mine branch local was derailing as it backed down my mine branch.  The branch was difficult trackwork, down grade, 18 inch curves, turnouts.  After weighting the Roundhouse coaches up to NMRA spec, the local could back down and out of the mine branch every time. 

If your road is running well, you don't have to do anything, just keep running. 

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Posted by NP2626 on Thursday, April 2, 2015 6:04 AM

BRAKIE

 

 
TomLutman
I really don't have issues with rolling stock jumping rails. What other advantages do you get with loading in the lead?

 

None..Good solid track work,correctly gauged wheels along with couplers  and trip pins at the correct height results in derailment free operation not added weight.

If a car is on the light side 2 or 3 stick on weights will even things up.

RP20.1 goes back to the days of light wooden car kits and less then  desirable  wheels.

 

If RP20.1 is obsolete; or, out dated than why hasn't the NMRA updated it lately to reflect that our equipment is so much better, today?  I should think that Recommended Practices and Standards would be in a constant state of review, to reflect the changing "State of the Art" in this hobby.

I have seen no reason to back off on adherence to RP20.1 and have found over many years that increasing the weight of a car to the RP’s suggested weight has almost always made the car a better performer.  

NP 2626 "Northern Pacific, really terrific"

Northern Pacific Railway Historical Association:  http://www.nprha.org/

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Posted by BRAKIE on Thursday, April 2, 2015 5:51 AM

TomLutman
I really don't have issues with rolling stock jumping rails. What other advantages do you get with loading in the lead?

None..Good solid track work,correctly gauged wheels along with couplers  and trip pins at the correct height results in derailment free operation not added weight.

If a car is on the light side 2 or 3 stick on weights will even things up.

RP20.1 goes back to the days of light wooden car kits and less then  desirable  wheels.

Larry

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Summerset Ry.


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Posted by "JaBear" on Thursday, April 2, 2015 3:45 AM
Weighing cars to the NMRA recommended weights, checking wheel gauge, and coupler height on ever car, is just something I decided to do. I can’t comment specifically on any benefits but I know that when I take my cars to run on others layouts that the guys like running them, up front, especially on long trains.
Cheers, the Bear.

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Posted by ricktrains4824 on Wednesday, April 1, 2015 11:17 PM

When I find lighter than normal railcars, my usual issue is not them "jumping" off, but, stringlining on curves, especially when I have a regular weight model, lighter weight ones, then regular (or even slightly heavy) weighted ones in that order on a train due to makeup while not paying the closest of attention to that detail...... 

I hate, even in HO scale, cleaning up a derailed train, especially when it just so happens to be the coal drag that also just so happens to have some simulated live coal loads using scale coal....Angry (Yes, a few of my coal cars had live loads, on top of a false bottom, to bring them up to specs on weight, and add a load while doing so. Now, after that happening just once, I've upgraded to hiding the weight under the false loads. Cool Ones that came with a simulated load already, just went right onto the layout after making sure the wheels and couplers were good. Black Eye I knew I forgot to check something! Dunce Bang Head) Can only imagine the mess the real 1:1 folks have to clean though... Dead

After I realized what was going on, my lighter models all got some "added muscle" in the form of fishing weights. Lot less of the stringlining events now. Now, all of my models that run are NMRA recommended weight, to slightly heavy, depending on model, age, diet and exersize.... Whistling 

Ricky W.

HO scale Proto-freelancer.

My Railroad rules:

1: It's my railroad, my rules.

2: It's for having fun and enjoyment.

3: Any objections, consult above rules.

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NMRA car weight
Posted by TomLutman on Wednesday, April 1, 2015 10:21 PM

Well, I was remodeling a recently purchased house and scored a TransAmerican scale. It's more of a commercial type scale with a .xxx readout in several different measures. First thing I thought of was weighing some rolling stock to see where it was, which turns out to be almost half of NMRA suggestions.

  I really don't have issues with rolling stock jumping rails. What other advantages do you get with loading in the lead?

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