Weighting Cars

[cjcrescent]

It should be noted, that although the RP was originally established in the 1950's, as was the RP.25, (wheels), both have been revisited, and revised several times, (RP20.1 was last REVISED in 1990), but through testing has still found that the basic RP still valid.

However, it is just a RP, and not a standard. On my layout except for resin cars, all cars are operated with the weight of the cars they came with as they were built. Resin kits are weighted to about 3 ounces for a 40' car. All the cars, wood, plastic or resin are weighted as low as possible keeping the COG low. Real cars are of different weights and in a GM freight, not all cars are loaded. So now the engineer has to contend with that weight difference in starts, stops, and curves on my layout.

While I'm DCC, I haven't programmed any momentum at all into my locomotives, (30 steam, 5 diesels). The only thing "extra" programmed in is a speed table, and except for the diesels and my passenger steamers, all locos are limited to about 45 SMPH. Drag locos are limited to about 35SMPH. The engineer has to rely on his skill on running his train. He has to start slowly or he may pull cars off the track, esp on a curve. He has to stop slowly or he may knock cars off due too a weight shift, esp on downgrades.

The Yardmaster has to block the road trains to help insure that the Road Engineer shouldn't have problems with his train due to weight, but also by destination. Overall I have found that when the engineer is careful with the train, there are no derailments.

[JoeinPA]

Antonio:

A postal scale is plenty accurate for weighing cars. They are available in office supply stores or even the post office. I have one that has been working well for several years. It is battery powered and has a nice digital display. I got it at Office Max.

Joe

[AntonioFP45]

A related question............

What are the opinions on digital scales?

There are a wide variety and I considered buying a small digital food scale that I saw at Walmart.  However, I was cautioned that those scales are not accurate. I'm just looking for something that can way objects in "Ounces", won't easily lose its calibration, and will last some years.

Suggestions?

[dstarr]

ChevelleSSguy

Now this is just my opinion. But I have found that NMRA's weight spec for HO is a tad too heavy for todays freight cars, and even those dating back to at least the late 80's and 1990's shake the box kits. I dont have much expierence with cars much older then the 1980s. Todays wheel sets and even older plastic kit wheel sets actually track quite well when they are in guage and a few members of our club believe they came up with the specification back when wheelsets very poor quality.

   Cars from the 1950's had a lot of metal in them and were heavier than today's plastic cars.  The railroaders who came up with RP 20.1 realized that it was a lot easier to ballast light cars up to weight than to lighten up heavy cars.   So RP 20.1 called for weights a little on the heavy side.

   I do clearly remember a long spur on my last layout that went uphill around some curves and thru turnouts on the grade.  I had one train that would pull into this spur, but just would not back out of it without derailing.  After ballasting the cars up to RP 20.1 standards,  that train had no further trouble on that spur.   There is a lot to like about heavy cars. 

[doctorwayne]

maxman

.......because you'll have one guy that would use the car out of the box without any additional weight, and the other joker who likes to fill his hopper cars with live loads.  They just don't work well with each other.....

In most cases, you're correct, but they'll work alright together if you exercise care in where the cars are place within the train.  I like to run live loads (total weight of about 8oz. for an Athearn 34' hopper).  If I stuck an empty Accurail USRA hopper (about 2oz.) right behind the locomotives, the trailing weight of a dozen loaded hoppers would likely cause problems with that empty.  However, place it directly ahead of the 4oz. caboose, and there's no problem.

maxman

.....Some others have made comments that the weight needed to get their cars to the recommended standard inhibits their ability to haul cars up a grade.  I would point out that when the recommended practice was established cars did not roll as well as most of them are capable of doing now.  Since the drag on the loco is now less due to the free rolling wheels, they should be able to pull more cars up the grade even with the same car weight.

I'm not aware of when that RP was established, but when Athearn introduced plastic wheels on steel needle-point axles, and in plastic sideframes, one of the big selling points was how well they rolled, especially as compared to the usual brass wheels on blunt steel axles in cast metal sideframes. 
While some current wheels are exceptionally free-rolling, many locomotives are lighter, sacrificing weight for space to accommodate lighting and other electronics.  In the old days, if your loco wouldn't pull enough, one simply added more weight - there was usually plenty of room for it.  

I suppose that if you're working within the constraints of a limited budget, it's not always possible to buy another locomotive if the train is too heavy for the one you've got.  However, I'd rather save up for that additional locomotive than lighten the cars.

For my layout, even with its many curves and 2.5% grades, I have most of my cars slightly above the recommended weight, and most of them are equipped with not-so-free-rolling trucks.  It works for me because I enjoy trying to wring more than the stock power from my locomotives.  If I had a switching type layout, or even one with less curves and less severe grades, I'd run cars at about double the recommended weight, as they act more like the real ones, especially when coupling.

A friend liked to weight his cars even heavier, and the trains always operate flawlessly.  It was especially impressive to watch 20 or 25 heavyweight passenger cars behind 5 or 6 Stewart F-units, knowing that each car weighed between 12 and 15 ounces.

Wayne

[maxman]

locoi1sa

   I do admit that some weight is OK but the NMRA RP is too much and should be revised and amended.

The problem, as I see it, is that everyone will have their opinion as to what a new recommended weight should be.  And then we will get nowhere.  Maybe you're able to interchange your cars with others at your club, but that wouldn't work at mine.  That's because you'll have one guy that would use the car out of the box without any additional weight, and the other joker who likes to fill his hopper cars with live loads.  They just don't work well with each other.

I understand your comment about making sure the Kadees are properly installed, and I don't slam the cars together either.  But I've got a couple cars that are so free rolling that if I gently pull the engine up to it to couple the car will roll away because the knuckles will not open to engage before the car rolls.

Some others have made comments that the weight needed to get their cars to the recommended standard inhibits their ability to haul cars up a grade.  I would point out that when the recommended practice was established cars did not roll as well as most of them are capable of doing now.  Since the drag on the loco is now less due to the free rolling wheels, they should be able to pull more cars up the grade even with the same car weight.

Anyway, each of us is free to have their own opinion on the subject.

Regards

[locoi1sa]

Jim.

 It is an RP. And I do interchange cars on the clubs layouts all the time. I also do not use traction tires or snot but do adjust and add weight to my locomotives. I also do a lot more important things to my rolling stock then stuffing weight into them. How many of you really follow the directions on the KD5 envelope?  Do you burnish, shim, and use either greasum or graphite to lube them? Maybe this is why I don't need to add a ton of weight to get my cars to couple? I also go a step further and weaken the centering springs so coupling is easier and never have to slam them. Sure I can weight my cars so I will need pushers on a 20 car train but I find it not necessary. I can also go up the clubs 38 foot long 2 percent grade with 2 steamers in front of 50 cars with 2 more steamers pushing on the rear. I can also stop this train on the grade and restart it too. I would love to add more cars but the runaround for the pushers to put the cabin back on the train is too short and the lead locos are already into the yard lead. The Helix down needs two more loops for a good 70 car train.

   I do admit that some weight is OK but the NMRA RP is too much and should be revised and amended. Like I said. My 36 foot milk reefer would be nearly half the weight of the 70 foot coach behind it. 

          Pete

[gmcrail]

The RP20.1 was developed when almost all kits and cars running had metal sprung trucks. (Athearn, Roundhouse, Silver Streak, etc.)  Then the accepted method of fastening trucks to car bodies was to tighten the screws snugly, then back the screw off 1/4 to 1/2 turn.  With the the heavier cars, this made the self-equalizing feature of the sprung trucks to function more smoothly, and the cars would thus ride over rough trackage better. 

The 3-point method of truck mounting was put into play when solid side frames became popular.

Personally, being pretty much old-school in most things, I prefer the sprung trucks.  And I try to weight my cars to the NMRA specs because they work.  Of course having a layout with no grades helps...

[maxman]

jrbernier

Loco1sa,

  That is not an NMRA  'RP' - It is Standard S-8.  I agree that with current technology, you can cheat the weight standard, but if you are going to reliably interchange your cars at the club - You need a common starting place.

 

Jim, I believe that you are incorrect on the standard vesus practice statement.  Standard S-8 appears to have something to do with track centers.  The weight recommendation is a recommended practice RP-20.1, http://www.nmra.org/standards/sandrp/rp-20_1.html.

That said, I agree with you 100% on your common starting point statement.  It seems that every so often in this forum and in other places (i.e.: down at the club) someone comes up with their idea of what proper weighting method is.  And there are always reasons why their method is "better".  So with 10 people, you get 10 "better" methods.  In my opinion, it is much better to follow a recommended practice and get the desired commonality.

Personally, I find the NMRA recommendation just about right.  With the recommended weights I'm not chasing light cars around the railroad when trying to couple to them, and I'm not trying to overload the cars with every piece of scrap metal I have laying around the basement.

[jrbernier]

Bob,

  I have never heard of RTV fumes attacking plastic.  The tube says that acetic acid fumes 'evolves' as the product cures.  Now, the fumes from Walthers 'Goo' will attack plastic when confined in a freight car and it is not fully cured.  I usually use automotive 'stick-on' weights,and run a dab of clear DAP silicone rubber sealant along the edges of the weights to insure that will not come loose sometime in the future.  I must have over 300 'house' cars and have never seen an issue.  Of course, I usually 'mass' weight a number of cars as I work on them and it may be a day or two before I do final assembly of the cars.  Any fumes should be long gone.

Loco1sa,

  That is not an NMRA  'RP' - It is Standard S-8.  I agree that with current technology, you can cheat the weight standard, but if you are going to reliably interchange your cars at the club - You need a common starting place.  Poor couplers/weight/wheels are a recipe for disaster.  We had a non-member 'visit' our club yesterday.  Between his train coming apart, derailing, and shorting out power districts - we had lots of problems.  During one of those derailment/power loss incidents, my train was in the same power district.  The decoder in the trailing unit got 'scrambled' and became unresponsive.  I took the unit off the train and had to reload the configuration from the Decoder Pro files - It then ran normal again.  Another train lost control and we had to 'pick up' the units as they were moving.  I had to do a factory RESET to one of the units to get it running again.  Unpainted metal trucks with old wheels and all metal engines that are looking to 'short out' are no fun. And most of the cars were under 3 oz

  I brought down 40+ cars to the club that had never been run before.  All were weighted to the S-8 standard, had metal wheels, and metal couplers.  Of those 44 cars, I only had 6 issues:

• 4 'trip pins' had to be adjusted
• 1 coupler knuckle was 'sticky'
• 1 set of trucks had to have the screw loosened a little

  All we 'fixed' within 5-10 minutes and operated reliably for the next 2-3 hours.

Jim

[cmrproducts]

I have found that not weighting my cars will cause many more derailments and with 1100 cars this is not something I want happening when I have an OPs Session and there are 20 guys running my equipment.

I have also found on many of the other layouts I run on the weights have come loose in the cars causing more problems than not having any weight at all!

I don't know that glue they use but I found that using Shoe Glue seems the best as I had used RTV Silicone and had some problems with the fumes given off by the RTV when curing was attacking the plastic.

This is why I changed over to Show Goo (available from Wal-Mart)  It isn't an RTV type of material and once it dries the wright is just about unremoveable - as I have had to do it and it is not fun!

At least my wights don't come loose any more!

BOB H - Clarion, PA

[hobo9941]

I have too many cars to weigh each one. If the car derails a couple times, for no apparent reason, then I weigh it and add weight. If it uncouples twice or more for no reason, I install Kadees. If it ain't broke, I don't try and fix it.

[OKrlroads]

Most of my rail cars are kits, built with metal wheel sets, trucks tuned, etc. My idea when first starting out was to lighten up from the NMRA standards, and haven't had a problem with derailments. But one thing I've noticed is that by bring the car weight up, the cars look more realistic rolling down the track. It eliminates the shake when going over a railgap or rolling thur a turnout. In other words a lightweight car will shake, a heaver one will roll a little, ( just like the prototype does over rough track ) then settles back down.

[ChevelleSSguy]

Now this is just my opinion. But I have found that NMRA's weight spec for HO is a tad too heavy for todays freight cars, and even those dating back to at least the late 80's and 1990's shake the box kits. I dont have much expierence with cars much older then the 1980s. Todays wheel sets and even older plastic kit wheel sets actually track quite well when they are in guage and a few members of our club believe they came up with the specification back when wheelsets very poor quality.

[cedarwoodron]

One more "aesthetic" aspect- a properly weighted car (in HO) makes a very satisfying clickety-clack as it travels on sectional track- just like the old days before welded rails. That is something that should not be overlooked in the process of weighting cars. Weighting also makes the cars seem less "toy-like" by giving them some "heft", if that makes any sense. Cedarwoodron

[dstarr]

RideOnRoad

In the gondola cargo thread, there was a reference made to removing the weights from the cars.  Could someone enlighten this beginner as to the practice of weighting cars?

In simple words, heavier cars are more likely to stay on the track, (less likely to derail).  Heavy cars are harder for locomotives to drag up grades.   The NMRA has published a Recommended Practice 20.1 for car weights which is a good compromise worked out by a lot of experienced model railroaders.  For HO the rule of thumb is one ounce plus an additional 0.5 ounce for each inch of car length. 

   Most commercial models are light.  A forty foot car ought to weigh 3.5 ounces.  You will find most of 'em only weigh 2.5 ounces.  Some weigh even less.   There has been much criticism of RP 20.1  over the years, most of the critics call for a lighter weight standard.   That probably works.  The important thing is to have some standard.  Light cars sandwiched inbetween heavy cars will be pulled off the track on curves, so you want  all your cars weighted to the same standard, either your own or the NMRA standard.

  For myself, I use RP 20.1 and it works well. 

[delray1967]

I have used many things for weights in the past but when I ran out of things to use, I found U.S. Pennies to work great and low in cost.  Between 10 and 15 pennies in a boxcar (if I remember correctly) to bring the standard weight up to NMRA spec.

For my Tichy 40 ft flat car, I had some lead wire pieces that I glued to the bottom of the trucks because there wasn't enough room on the underframe (which has lots of detail).  I only added as much as I could without being able to see it from typical low viewing angles (just in case some rivet counters get up close. lol).

Keep it as low as possible so you don't raise the center of gravity too much.  Washing your hands after handling lead is a good idea, or wear gloves (and still wash your hands).

[locoi1sa]

 I know I will be getting a lot of flack over this but I have a differing opinion on the NMRA RP for weighing rolling stock. First it is a recommendation and not a standard. Second it is antiquated at best. Born at a time when track was rudimentary and mass production was shaky in tolerance. Most ties were either wood or fiber that swelled and shrunk. Rolling stock had those giant flanges that could slice your grilled cheese sandwich with ease. 

 Concentrating on more important things is conducive to better overall performance. Track work, free rolling metal wheels in square trucks, properly adjusted and operating couplers, and a three point suspension is more important than tossing in a few ounces of lead to cover up a problem. Weighing your rolling stock to a consistent weight instead of by length of car would be operationally better. For example If I make up a local with a couple of 36 foot reefers in front of a couple of 72 foot coaches for a local milk / commuter run the coaches would out weigh the reefers by a considerable bunch. In front of those is an old 2-6-0 with a shorty tender that would weigh half of one coach. Now for example they all weigh 2 1/2 to 3 ounces then you would have a better chance of not pulling one of those light reefers off the rails. I have found that I need not add any more weight than what the manufacturer put in the kit to begin with. I do add free rolling metal wheels and make sure the car goes through my inspection and tuning track before it goes on the railroad.

         Pete

[joe323]

I never found the need for a fancy scale. An old diet scale i picked up at a rummage scale works fine for me as a weigh station. Do however weigh the cars as it does make a difference in performance.

[cedarwoodron]

I agree with Jonessy- those NMRA standards make more sense the more I rebuild and properly (as per NMRA) weight cars in my rolling stock inventory, now over 100 cars. I weigh the car as is, whether it is an already built Athearn BB, a NIB car, an old Kline I liked at that last swap meet, or even one of my newer Atlas RTR purchases. Then I add weight to bring it into compliance. The newer RTRs are generally close to the mark, but I have added weight on afew as well. I heartily recommend getting a nice digital scale (Harbor Freight has some inexpensive ones) to get accurate readings. I use lead fishing weights of 1/2, 3/4, 1.0, 1.5 and 2.0 oz sizes which I can hammer into nice flat blocks, or cut them as needed to get the right amount needed for weighting a car. Don't be afraid of loads in a hopper or gondola or on a flat car. They can hide weights quite easily, if you are creative. Loads make these cars more visually interesting and remember, a car with a load pays its way on the railroad! Cedarwoodron

[jonessy]

this is the method i use 

http://www.micromark.com/html_pages/instructions/84016i/84016carweight.htm

[jeffrey-wimberly]

I have two Bachmann depressed center flat cars that were a bit shy of weight. To weight them I added Norscot Caterpillar equipment. Two 315CL excavators and a D5G bulldozer on one, two D5M bulldozers and a 315CL excavator on the other. Even though they were more than sufficiently weighted I still wasn't happy and went for overkill. I disassembled the Cat equipment  and pack all the available space with modeling clay then reassembled them. There would be a long heavy train behind these cars and I didn't want them flipping over as they were prone to do as lightweights.

[jrbernier]

  The above mentioneds NMRA standard is a very good start.  The object is to have a consistent weighting scheme.  Box Cars, Stock Cars, Reefers & Covered Hoppers usually are no problem - there is lots of space inside the car body to add weight.  I like to use the 'stick-on' weights from automotive supply outlets.  Note that most of the weights are now steel, not lead and are larger than the lead balance weights.  Some folks use old pennies as well.

  Flat Cars & Gondolas can be tricky.  I have been using #9 lead bird shot that I pour into the center sill, and sometimes around the under body to try to get them close to the spec.  I use diluted Matte Medium to 'glue' the bird shot in place.  It takes several saturation's to get it all glued in place.  I like to use Matte Medium as if dries sort of elastic, not rock hard like white glue.  Loads can also be used to add weight.  When using the lead bird shot, make sure you wash your hands after working on your models!  And you can still find lead bird shot - In bulk it is about $40/25 lbs, plus shipping - You will have a 'life-time' supply(share it with your fellow modelers).  I used to use #12 bird/snake shot - but I have not been able to find it in bulk anymore.

  For open Hoppers, I fill the discharge bays with lead bird shot, covered with some loose HO coal, then saturate it with Matte Medium.  It looks like the car was not completely cleaned out.  Most of the time it still is not up to the 'spec', but it is close and a cast 'load' will be more than enough to bring it up to weight.

  Tank Cars have their own special issues.  While there is plenty of room inside the tank for weight, most RTR cars are really glued shut pretty good!  Trying to pry off an end cap can damage the car.  Sometimes I have had to drill a small hole in the bottom and use the bird shot.  I dribble in the Matte Medium, plug the hole and right the car so that the bird shot/glue is now on the bottom.

  I find that a combination of proper weight & free rolling trucks seem to give the cars more 'heft' and they seem to roll better even on the flat.  Coupling is much smoother as well.  All of my plastic side frame trucks have been reamed out with the 'Truck Tuner' tool, and have metal wheel sets.

Jim

[BroadwayLion]

Car falls off of track: It is not heavy enough.

Train will not go: car is too heavy.

I make my cars as heavy as possible as long as the trains can make the grades and hold to the schedule.

LION uses push-pull equipment, power can be anywhere in the consist, some of it is strung out and some of it runs buffed up.Gotta stay on the tracks. Him likes using printer's slugs for weight, unfortunately, letterpress printing as gone the way of the steam engine.

Yes, Yes, LION node dat NMRA has standards, but LION has different reality. Him can only use stuff he finds around the zoo.

ROAR

[Rastafarr]

Cars have minimum recommended weight under NMRA standards to reduce operational problems (stringlining and so on). Check it out here:

http://www.nmra.org/standards/

The manufacturers don't always get this right, so it's common for people to squirrel away weights in hidden sections of their rolling stock (automotive wheel-balancing weights work pretty well, but there's lots of other options).

Hope this helps!

Stu

[RideOnRoad]

In the gondola cargo thread, there was a reference made to removing the weights from the cars.  Could someone enlighten this beginner as to the practice of weighting cars?