About car weight

[foulrift]

I have read many posts dealing with adding weight to rolling stock to improve performance.
My layout is small,only 2'x8' without any real curves so given that would it be necessary to add weight? This is a switching layout and I won't be running at warp speed either.Your thoughts. Bob

[nachoman]

I would leave them alone unless you have problems with derailments now. Lighter cars tend to derail easier, but cars that are too heavy are difficult to pull and your locomotives can't pull as many. I think a general rule would be to make your cars as light as possible until they derail.

[Russ Bellinis]

When ever you push a car through a curve (like the diverging route through a switch), you introduce side forces that will make the car want to derail. Body mounted couplers are less prone to this problem than talgo mounted couplers. I think the best way to find out is to build your rolling stock so that you can add weight if needed, and then see how they perform. If the cars are too light, they will derail when you try to use them. Of course, the cause for derailing may be any number of other problems like wheels out of gauge, trucks bent or too tight, tracks out of gauge, or even too tight of a radius for the equipment you are using.

I have found that even though they are a little bit light compared to NMRA recommendations, Athearn blue box kits will work pretty well. On the other hand the early Intermountain 89 foot flats were notoriously light and without a load to add weight, they would derail very easily.

[foulrift]

Kevin,Russ-Thanks.As stated I'll just wait until I actually start running and if there is a problem then I can add weight.It's only the box cars that really concern me as most of the other cars have loads on them adding some extra weight. Bob

[RobertInOntario]

I would agree to only add weight if & when you need to. Usually, adding weight helps but can backfire by simply making a train too heavy to haul, especially if all the cars are heavily weighted. Rob

[BR60103]

If you put a really light car at the front of a train it can be pulled off on a switch.
Another problem with light cars can be couplings that don't mate but just push.

[Roger Hensley]

At the risk of sounding trite, I will state the NMRA RP-20.1 Car Weight figures here. The RP is a Recommended Practice and does NOT carry the same responsibilities as a Standard. Now, that said, it is a very goo recommendation for good operation.

Quote:
Carefully documented tests, show a decided advantage in performance past obstructions in the track for cars weighted to an optimum weight. Since the radial forces tending to cause derailments are greater in longer cars, this optimum weight will vary with car length.
Unquote:

SCALE INITIAL WEIGHT + ADDITIONAL WEIGHT per inch of car body length
This means that:
HO = 1 ounce + 1/2 ounces per inch of car.

In other words a 6 inch car should weigh about 4 ounces.

That's all folks. :-)

[foulrift]

Points well taken,all valid.I think,as I stated above,I'll wait and see how the cars run before adding weight.Bob

[eightyeightfan1]

Its a known fact that Athearns older BB rolling stock is lighter than the NMRA standard.
Adding one or two 1/4 ounce tire weights usually bring them up to standard.

[foulrift]

Thanks 88-BTW check your PM

[nomad]

Bob, if you do need to add weight, you can go to your local tire dealer and ask to buy some strips of "tape on wheel weights".Theses are lead weights with double sided tape. My tire dealer usually gives me three or four. Same thing you see selling for $3.98.

Loren

[P5se Camelback]

At the risk of sounding trite, I will state the NMRA RP-20.1 Car Weight figures here. The RP is a Recommended Practice and does NOT carry the same responsibilities as a Standard. Now, that said, it is a very good recommendation for good operation.
...
SCALE INITIAL WEIGHT + ADDITIONAL WEIGHT per inch of car body length
This means that:
HO = 1 ounce + 1/2 ounces per inch of car.

In other words a 6 inch car should weigh about 4 ounces.

That's all folks. :-)

I totally agree with Roger. You never know when one of your pieces of rolling stock might spend an evening visiting the layout of a friend, and If your friend is like my friends up in Pennsylvania used to be, the car had to go through a check list before hitting the rails ... coupler height, wheel gauge, weight, etc. ... all the NMRA Standards and many of the RP's.

To me, it just makes good sense and helps eliminate one more cause of frustrating derailments.

bil

[RobertInOntario]

I would leave them alone unless you have problems with derailments now. Lighter cars tend to derail easier, but cars that are too heavy are difficult to pull and your locomotives can't pull as many. I think a general rule would be to make your cars as light as possible until they derail.

I basically agree with this advice, above. I've added weight to 1-2 of my freight cars, if I have persistent problems -- yet I'm still not 100% sure if it has really helped. Rob

[RobertInOntario]

I don't want to go off topic, but I usually run 1930s-'60s, short, 4-wheel, freight cars on my British 00 layout. I find that these cars are more sensitive (especially if they're really light) & prone to derail than their North American equivalents. Trouble-shooting these cars can be quite different from fixing the 2-truck/8-wheel kind. Rob

[Gary S]

I weight my cars somewhat heavier than NMRA standards. Reason is because I use permanent magnet uncouplers under my spurs and the extra weight helps keep the slack out of the couplers when going over the magnets and not wanting them to uncouple.