NMRA weighting putting a fine point on subject

I haven't found that it makes a significant difference if the coupler length is included or not. But the standard says car length which I take as meaning bulkhead to bulkhead.

Bogie

NMRA standards were developed for scale trains with rails and wheels closer to scale and wider curves. The car weight standards are less applicable to 3-rail trains IMO. Unfortunately the NMRA doesn't actually have suggested wheel and rail standards for 3-rail because they are considered "toy trains", out of their realm.

Of course it does make sense to have some consistency with car weights for 3-rail, especially if you want to run longer trains. But some of us choose not to do too many modifications on postwar-era trains. I run one train with 30+ cars (many postwar) and just put the lighter cars towards the rear of the train. If I added weight to the lighter cars I couldn't pull as long a train because it would have "bowline" derailments on the O54 - O72 curves.

Even real railroads have rules about placement of empty cars depending on various conditions. For example, not putting empty piggyback cars at the head end.

Ace posted:

NMRA standards were developed for scale trains with rails and wheels closer to scale and wider curves. The car weight standards are less applicable to 3-rail trains IMO. Unfortunately the NMRA doesn't actually have suggested wheel and rail standards for 3-rail because they are considered "toy trains", out of their realm.

However, if one is a 3-Rail SCALE modeler, those NMRA weight standards work just fine.

Of course it does make sense to have some consistency with car weights for 3-rail, especially if you want to run longer trains. But some of us choose not to do too many modifications on postwar-era trains. I run one train with 30+ cars (many postwar) and just put the lighter cars towards the rear of the train. If I added weight to the lighter cars I couldn't pull as long a train because it would have "bowline" derailments on the O54 - O72 curves.

 

Hot Water posted:

However, if one is a 3-Rail SCALE modeler, those NMRA weight standards work just fine.

OK, I'm not familiar with "3 rail scale". It's a smaller niche of the whole 3-rail picture, and this post is in the "traditional" category. Does "3 rail scale" have "recommended standards" for scale wheels, scale rails, scale couplers, wide curve radii? Or is it "scale" more in terms of layout decoration?

Consistency of car weights is more critical mainly with longer trains with more-scale wheel and rail standards. Most 3-rail equipment has relatively huge flanges which substantially compensates for lack of standards.

On the original question, NMRA weight standards are based on car body length, not including couplers.

http://www.nmra.org/rp-201-car-weight

Ace posted:

Hot Water posted:

However, if one is a 3-Rail SCALE modeler, those NMRA weight standards work just fine.

OK, I'm not familiar with "3 rail scale". It's a smaller niche of the whole 3-rail picture, and this post is in the "traditional" category. Does "3 rail scale" have "recommended standards" for scale wheels, scale rails, scale couplers, wide curve radii? Or is it "scale" more in terms of layout decoration?

I suggest you visit the 3-Rail SCALE (3RS) Forum, to learn what has been going on for the the last 3 to 5 years. MTH has been offering, for many years now, freight rolling stock with Kadee coupler pads included in the box, and Lionel has been offering freight cars with Kadee compatible mounting pads. Obviously it is NOT as "smaller niche" as you seem to imply.

Consistency of car weights is more critical mainly with longer trains with more-scale wheel and rail standards. Most 3-rail equipment has relatively huge flanges which substantially compensates for lack of standards.

On the original question, NMRA weight standards are based on car body length, not including couplers.

http://www.nmra.org/rp-201-car-weight

Actually, I think this is one of the best NMRA standards out there, and is equally applicable to all flavors of "O" trains, both scale and traditional. The reason it works, regardless is, it is based on car length.

In the 3 rail world, we may not need to be quite as precise. Our oversized flanges provide us a little leeway, but it is still a good idea to add weight to any car that deviates grossly from the standard. Flat cars are a prime offender.

Just for fun, I grabbed one each of the Lionel 86' box cars and 89' auto racks off the layout and threw them on the scale. Both weighed in at 25.3 oz. Doing the math according to the standard, the box car should weigh 26.5  oz and the auto rack 27.25 oz. I don't plan to add weight to either, that's close enough. Beside, adding the extra weight will probably not gain any advantage, and adding enough over the length of a train will eventually force you to knock a car off the end because the engine can't pull it.

BTW RRMAN, measurements should be end to end on the car body, not knuckle to knuckle.

I use the 5oz + 1oz/in, that has worked for anything I've done.  I managed to pull 115 cars with two locomotives with them weighted that way, so I'd suggest it's good enough for 99% of the users.

Hot Water posted:

Ace posted:

NMRA standards were developed for scale trains with rails and wheels closer to scale and wider curves. The car weight standards are less applicable to 3-rail trains IMO. Unfortunately the NMRA doesn't actually have suggested wheel and rail standards for 3-rail because they are considered "toy trains", out of their realm.

However, if one is a 3-Rail SCALE modeler, those NMRA weight standards work just fine.

 

 

Not only that, the NMRA does have standards for Hi-rail track and wheels!

http://www.nmra.org/index-nmra...ecommended-practices

Might want to actually look S-3.3 and S-4.3  There is also an S-1.3 on general Hi-Rail

Here are the links to the specifically hi-rail standards pages MWB referred to:

http://www.nmra.org/sites/defa.../S-1.3%202009.07.pdf  (General - Scales with deep flanges)

http://www.nmra.org/sites/defa...3.3%202010.02.24.pdf  (Standards - Deep flanges for guarded track)

{Guarded track encompasses special trackwork such as turnouts and crossings)

http://www.nmra.org/sites/defa...4.3%202010.02.24.pdf (Standards - Wheels with deep flanges)

While the standards do not address third rails (either center or outside), in my opinion it still would be a big step forward if the hi-rail manufacturers would commit to these existing NMRA standards for the wheels and running rails.

mwb posted:

Not only that, the NMRA does have standards for Hi-rail track and wheels!

http://www.nmra.org/index-nmra...ecommended-practices

Might want to actually look S-3.3 and S-4.3  There is also an S-1.3 on general Hi-Rail

True, but getting all manufacturers to comply has been the problem. Let's not even talk about couplers.

The nice part of the weight standard is the manufacturers don't have to do anything special, compliance is up to the customer.

Then there are some 3 rail standards that need to be corrected. If someone was going to create a new standard for track work it should be Ross.

The TCA is not a substitute for the NMRA. The NMRA has nothing to do with the grading of trains and boxes, and everything to do with how they function. These standards don't write themselves. They need active, interested people to create them. I quit the TCA 10 years ago, but I'm still a member of the NMRA, going on my 43rd year.

Big_Boy_4005 posted:

mwb posted:

Not only that, the NMRA does have standards for Hi-rail track and wheels!

http://www.nmra.org/index-nmra...ecommended-practices

Might want to actually look S-3.3 and S-4.3  There is also an S-1.3 on general Hi-Rail

True, but getting all manufacturers to comply has been the problem. Let's not even talk about couplers.

The nice part of the weight standard is the manufacturers don't have to do anything special, compliance is up to the customer.

Compliance is voluntary and the 3-rail manufacturers fail to grasp that accepting standards will work to everyone's benefit.  You either work around that on your own or you don't buy their stuff.....

Was bit by the 3RS bug a while back. So K-D's on my cars, small flanges, etc. I have a collection of Bettendorf trucks with the old 172 flanges that are a tad more reliable on the Club's (AGHR) GarGraves track, some of which was indifferently laid. Anyway, if necessary I replace tinplate trucks with those or with Athearn/Intermountain-wheeled trucks.

Not a big fan of the NMRA weighting standard. If the trucks are properly mounted, not skewed or warped, and turn freely, my cars run fine at somewhat lower weights. Heavy-weighting cars is a compensation for poor trucks and wheels.

One more thing: at this website  http://www.railwayeng.com/rrhints.htm#q1 the manufacturer has some pithy comments about the conflict between wheel and rail standards. Basically, NMRA standards for track are too wide for the standards for wheelsets. So NMRA compensates by specifying upweighting rolling stock to compensate.

rex desilets posted:

Was bit by the 3RS bug a while back. So K-D's on my cars, small flanges, etc. I have a collection of Bettendorf trucks with the old 172 flanges that are a tad more reliable on the Club's (AGHR) GarGraves track, some of which was indifferently laid. Anyway, if necessary I replace tinplate trucks with those or with Athearn/Intermountain-wheeled trucks.

Not a big fan of the NMRA weighting standard. If the trucks are properly mounted, not skewed or warped, and turn freely, my cars run fine at somewhat lower weights. Heavy-weighting cars is a compensation for poor trucks and wheels.

How many cars do you have in your trains? I find properly weighted freight cars, no matter what the trucks/wheels are, seem to track better, especially backing through yard turnouts, for set-outs on long trains, i.e. over 30 cars.

The Club limits me to 20 forty-foot cars. I can back a train (slowly) through facing point Ross switches.