Lighter

I do mine at 75% of NMRA standards.

Passenger Cars--I double the weight

All of my passenger cars have double the recommended NMRA weight. Smaller headend cars have the same amount of weight as well. My passenger trains track with very little problems.

Hiding weight

I think you can still get sheet lead from roofing supply companies.  I got sheet lead from a hobby shop years ago, but doubt that it is available anymore.  The other possibility if lead is not available is to use sheet steel @ 1/8 inch thick from a local metal supplier.  Cut it to just fit the underside of the flat car body and fasten it between the car body and frame.  Steel can also be used in the same way between a gondola's frame and body and on both sides of the slope sheets of hoppers cars.  The third method of hiding extra weight on open cars that you don't want to hide weight in loads is to get the bird shot from a gun store or sporting goods store that sells reloading supplies to hunters, and hide it in crevices with epoxy.  Just remember to take proper precautions when using lead and make sure it is sealed by paint or epoxy and wash your hands thoroughly when finished handling it.  Don't smoke, snack on anything, or put your fingers near your mouth for any reason while handling lead.

"wondering if others are going above the NMRA standard "

    I like my cars as light as possible, as long as they stay on the rails I don't add weight. I think free rolling trucks with correct wheel profile are more important than car weight and suspect that excess weight would hasten truck bearing wear. Also easier on a loco to pull less weight than to pull more weight. Of course if one has to use extra tight curves then some extra weight might help keep long trains on the rails but that's a problem I hope to never have, I've pulled and pushed  short cuts of light weight cars around a 90 foot radius so know extra weight is not needed to model the Harlem Transfer :> ) ...DaveBranum

Does length matter?

Almost all of the formulae I've seen for model railroad weight include the length of the car, and I've never really understood why.  Does it make a difference operationally if an 80' car is the same weight as a 40' car?  It's the same weight per truck, so if the point is to keep the trucks pressed down on the rails, then length shouldn't matter.  On the other hand, I can see that a longer car might have more tendency to derail in a sharp curve, and more weight might help there.

So, has anybody evaluated the WHY? of the formulae we use, or just the WHAT?

Lateral force

I would think that the longer the car is the more chance of lateral force and the added weight helps over come that lateral force.  If on an arc, you pick a point draw a chord on either side the length of your cars, the angle between two will be greater the longer the chords (cars) are.  The greater the angle the greater the lateral force.

That's why I go light on the standards, I model 1900-1905, the vast majority of my cars are in the 30-36 ft range. 

ou can probably go light with short trains.

The problem is that different dynamics occur as train length goes up as well as the effect of grades, curves, etc.  If you are running a 5 car train with short cars, light weight probably won't hurt.  If you are running 30 car trains with longer cars, a lot of grades and curves, you will need more weight.  One size does not fit all.

My thoughts on weight

I model 1895 C&O in HO and most of my cars are 32-36' in length.

I weight my car a little heavy compared to NMRA weight standards by not by much.  In fact the heavy weight is more for convenience than anything else.  As an example, my 32' to 36' cars are between 4.5" and 5" long and should weigh from 3.2 - 3.5 oz. Most of my cars typically weight between 3.4 and 4 oz.  I use what ever is at hand (nuts, pennies, lead) until I am over 3.5oz. My 50' passenger cars are weighted at over 4.5 oz.

Where I differ is, why should all cars weigh the same.  It never made sense to me that an empty flat car and a "full" box car should weigh the same.  Now I would never go so far to suggest that we weight box cars differently to simulate a full and empty box car.  However, I do not attempt to make my empty gondola, hopper, and flat cars weigh as much as my enclosed cars.  As an example my removable coal load for my gondolas weight about 2 oz. My empty my gondola weighs about 2 oz, but fully loaded it weights about 4 oz. (3.7 - 4 oz)  

Our full scale counterparts have to adjust for cars of different weight and so do I.  It would not be advisable to pull as string of empty flats in front of several heavy boxcars around a tight curve.

Art

Lets go fishin

I go a little over on weight, I like the idea of 1 oz per inch.

I use lead sinkers for weight. Lots of different sizes to choose from.

Lead shot

#12 Lead Shot, from your local fire arms dealer, works well for adding weight to empty flatcars.  Use Zap-A-Gap or other similar type glue to add it to the underside of the car.

more or less weight?

It would be interesting to see a scientific analysis of the weight per car effect on train stability using different curvature, grades, and train lengths.  On one hand more weight pushes down on the cars making it harder for the flanges to jump the rails but more weight also increases drag and drawbar pull needed to move the train making it more inclined to jump off the rails. In practice I've seen more long trains in N scale where the cars are light and free rolling than I've seen in O scale where the cars are heavy  and hard to pull.....DaveBranum    

The new wheels require more weight

Want prototype operation? - forget about the NMRA standard!

Thanks Mike M. for bringing this up. I was going to post this at some point, knowing full well that there would be plenty of naysayers to weighing freight cars to this extent.

Bottom line, if you want really reliable operation, and more importantly, prototypical operation, you should consider adding a LOT more weight to your freight cars. throw the NMRA standard out the window. It's wimpy.

My proto-freelance Allagash Railway is set in 1980. We run heavy trains over terrain that is seldom flat. We have a couple of very nasty grades and a lot of curvature. I generally weight my 40' and 50' boxcars to between 9-12 oz. Same for covered hoppers. I use lead wheel weights. These are the little 1/2 oz or 1/4 oz self-adhesive strip weights that are used for wheel balancing. I get them by the box at my local auto parts store, instead of getting ripped off by the ridiculous A-Line weights for $5 a strip. Do they still make those? What a scam! A box from the auto parts store will last a long time, depending on the number of cars you need to weigh. I've gone through many boxes over the years. The guy at the counter always seems like he wants to ask me.."hey what are doing with all this lead anyway?"..but he never does!

For boxcars and covered hoppers, depending on how the car is built, I carefully pry the roof off and stick the lead strips to the lowest point in the inside (belly) of the car. I'm generally adding 6oz or so. The roofs on the new offerings from Tangent and Exactrail pop right off for an easy install. Kadee boxcars I take apart, or stuff the weight inside the door opening. Wherever I can get it so that it is not visible. For tank cars, I have to get a bit radical. I actually drill a hole in the bottom of the car and fill the car, to the brim with sifted play sand. Open hoppers are tricky, as are flats. Pretty much have to deal with them being light, and block them in the trains accordingly...on the rear. There are probably ways to solve these as well, but I haven't experimented yet.

As-delivered these cars are all featherweight. Add the tonnage and the cars stay on the track, and they ACT like a freight car should (more prototypical switching and inertia, real tonnage simulation). They don't jerk and jump around when switching. This tonnage, combined with lots of momentum on the locomotives actually creates a more natural response.

If you want to really simulate tonnage, you have to add weight, and lots of it. Locomotives call pull way too many out-of-the-box freight cars. The tractive effort, or tonnage rating, of a typical HO loco is way too high, especially on grades. To get a typical 25-30-car train up the 2.9% ruling grade over Holman Summit on the Allagash we NEED 4 or 5 units (4-axle Atlas or Proto 2K GP38s or Atlas C420/C424/5 for example). In other words, we don't just put 4 or 5 on the train to make it look good, if we go with 3,we're probably going to have to double the hill. This is prototypical. The Maine Central RR put 4-6 units on a 35-60-car train to make Crawford Notch. Other mountain railroads do the same.

The point here is to create a situation where you NEED the power to get the tonnage over the road. Not only is it prototypical, exciting and more interesting, but everything runs and rolls better, and we have zero derailments...and I mean zero. The only car that derailed at the last op. session was an Intermountain 4750 CH that I can't seem to pry the roof off to get weight in it. Off the railroad and onto a shelf it goes.

I've never had a coupler fall out or a loco problem, and we operate regularly. A friend of mine lovingly predicts that I'm going to burn out a motor or decoder someday! Baloney! Make your locos work a bit. They can more than handle it. So far, so good.

Only word of caution. Use Kadee metal couplers..5's or 58s. Throw the plastic ones in the trash. Beyond that, get to the auto parts store and buy a box of wheel weights. You won't believe the difference!

Mike Confalone

"Open hoppers are tricky, as are flats"

   That's one of the benefits of running all the cars as light weight as possible, one can then mix and match the cars without worrying about  heavier cars throwing  lighter cars off the rails. As long as they are all well tuned and near the same weight cars can be less than the NMRA standards and still work fine. Railroads haul trains of empties all the time with no more trouble than hauling loads unless they are running in a strong wind, it's when they mix heavy and light cars that the trouble starts. The NMRA standards are a good middle ground for weight and work fine as long as the manufacturers adhere to them. If they build under weight it's easy to add a bit to get into the range but if they build over weight it's harder to remove the excess weight. The way I view it if the trains stay on the rails with less weight then I'm avoiding some equipment wear and tear maintenance over time,am saving some money,and not spending the time required to tear a car apart to add lead.If the trains are too light for the number of locos  I can always turn down the throttle or use the momentum feature. My O scale trains are much heavier than my N scale trains but I can run either of them at a realistic speed......DaveBranum

Gonna try Mikes suggestion

I have a couple of boxcars that I just can't seem to get them to run around the layout without derailing somewhere. So Mike, I am going to try your suggestion and weight them down significantly more and see what happens. My layout is flat so no grades to contend with. I'll let you know the results.

Mike is right

I agree with Mike 100%. However, I do run steam and they need lots more tlc than the diesels. I hate it when my 2-10-2 can only pull 30 light 40 foot boxcars.

Sheet Lead Source

Here is a source for sheet lead:  rotometals.com

Sheet lead really helps with empty flats, gons, and open top hoppers.

" a couple of boxcars "

Unless they are significantly lighter than the other cars there's probably something wrong with them mechanically that makes them derail. Check the coupler swing, The bolster screw tightness, the truck equalization, etc. before adding weight. There's no reason two defect free cars  should fall off where other cars run fine. If they check out mechanically and are underweight bring them up to the same weight as the rest of the cars and they should run the same.Unlike the real railroads we don't get paid for the tonnage hauled so more weight is an expense not an income on our bottom line :> ) .....DaveBranum

Can't say enough about this part!

I fully agree with this statement from Mike!

Tried everything else

Dave,

I have done everything you suggested and then some to get the cars to run well and they just don't seem to want to cooperate. So I did try the weight thing last night. Problem is I usually use pennies as my weight source since they are so prevalent. It took 50 pennies just to get the car to 9 ounces. But boy does it track good now! But I need to get some of that sheet lead I guess. Getting car up to 10 or 11 ounces could get pricey if I just use pennies.

A big pile of pennies

Lead wheel weights

Go to the auto parts store and get the lead wheel weights. They are easy to use, and economically priced in quantity. Unless you are in a state that has banned them, they should be available.

Glad to hear your car is tracking well. Amazing what a little tonnage can do!

Mike Confalone.

Lead Wheel Weights

Checked my local auto parts store online. They have different weights from .25 oz on up to 3oz. A box of 50 in 2oz increments is $37.99. So it would take 5 of them to get up to 10oz..and 50 in a box means only 10 cars. I'm still looking to see if I can find a better price.

lead wheel weights

That seems a tad pricey. They are certainly not cheap, but maybe not quite that high. I look at it this way, if it costs me $2 per car to add weight, it's worth it since it's a long-term investment.

Keep in mind, you don't HAVE to reach 10oz. If you got it up to 7 or 8oz, still a major improvement.

MC