Seems to me that I’ve read something about a two ounce average but I can’t remember. I use Kadee and McHenry couplers and would like to know what the correct weight figure is to make these couplers work correctly. Most of my older cars seem heavy enough and some are possibly too heavy such as some old cast metal cars from Roundhouse. I have seen some cars for sale on ebay that have been weighted to 4 and 5 ounces. Is that too much? I have not weighed any of my own so I can’t say where mine fit in but I know when one feels too light and it’s pretty obvious that the builder did not use any weights. What do you guys recommend for average weight? Thanks for your help.
The National Model Railroad Association (NMRA) recommended weight is 1 oz plus an additional 1/2 oz per inch of actual car length, for HO scale rolling stock. There has been a lot of discussion (and controversy) over this recommended weight in these forums in the past due to the fact that the NMRA’s RP was established many years ago and should perhaps be revised.
I use a simplification of the NMRA system on my HO Siskiyou Line – 1 oz per 10 scale feet. This gives you a slightly heavier car than the NMRA standard, but it’s easy to remember and the cars track well.
So a 40 foot car will be 4 oz, 50 foot car 5 oz. and so on. I weight closed-top cars with pennies – roughly 10 pennies to an ounce (where else will you find small weights for 10 cents an ounce?) … and I fasten them down with double-sided foam tape. I got a 300 foot roll of the foam tape at Office Depot for about $20. [swg]
For open top cars I replace the car weight with sheet lead. A-Line/PPW sells sheet lead in all different thicknesses.
At one time (I think) NMRA recomended 3 1/2 oz for a 40 ft car and 1/2 oz more for every added inch over 6. I started w/ that and it works for me so I kept it w/ one exception. I have a hump yard w/ 3 facing point switches at the base of the hump and. contrary to what one would expect (the longer the car the more likely derailment) I have most of my trouble w/ 34’ covered hoppers. I have to slug them to about 4 oz. Other than than that the above works well (and I shove 25-30 car cuts up the hump through those 3 facing point switches)
I took the 30 ton empty weight of an average freight car and divided it by the scale of 87 and an HO scale car should weigh something like 689 pounds. I would love to see the bench work that can hold up a train of those babies!
Actually, weight is a measurement related to volume, which is 3-dimensional. So you need to divide by 87 three times to account for downscaling all three dimensions – if you do that you will find the railcar should weigh a couple ounces empty, or four to five ounces loaded. Right where it should be!
You want all your rolling stock to weigh about the same. If you have light cars and heavy cars in the same train the heavy cars tend to pull the light cars off the track going around curves. And long cars want to be heavier than short cars cause the couplers tug the car sideways on curves. The sidewise tug gets stronger as the car gets longer. The NMRA recommended practice was written back in the days before plastic injection molding when rolling stock had a lot of heavy Zamac casting in it. Like complete cast Zamac undercarriages. Since it is very difficult to lighten a car, the NMRA standard was set a little heavy to accomodate the substantial numbers of heavy cars in service in those days. And once a standard is established, nobody wants to change it. I mean who wants to reweight every car in their fleet?
I use the NMRA recommended practice on my layout. In several cases derailing cars straightened out and stayed on the track after I weighted them up to the NMRA recommendation. And if you interchange your rolling stock on friend’s layouts or down at the club, you will find that most folk follow the NMRA recommendations and your rolling stock will work better if you do too. On the other hand there are folk who weight to a much lighter standard, claiming it is enough to stay on the track and it lets their locomotives handle longer trains up the grades. Your mileage may vary.
I use an old diet scale I picked up at a rummage sale to weight my cars. Because I am running a switching layout I am not concerned if the cars come out slightly heavier than NMRA standards since the longest train I run is about 6 cars.