What is the weight per inch for N scale cars?
.5 oz plus .15 oz per inch. See chart on page 58 of Feb '03 MR
Proper weighting of cars, like proper height of couplers, calls for discipline and a refusal to fool yourself into thinking that close enough is good enough.
I have copied the NMRA standards (for HO in my case) and post them above my workbench, right near the digital scale I bought for this purpose. I also created a “cheat sheet” for weights for standard lengths of car: 34’, 40’ 50’ and so on. I keep various weights nearby as well as a supply of double sided tape and Walthers Goo (remember to vent Goo or the gas will expand the car!). As for weights I do have the commercial lead weights in 1/4 and 1/2 ounce increments, but I also look for bits of metal on the street, such as nuts. A really good weight is the circle of steel that electricians knock out of a junction box. They are to be found everywhere at a house construction site.
Dave Nelson