scale weight for OO scale wagons

I understand thet there is a recomended weight
for trains & wagons how do i caculate this weight
and how do i obtain this

Hello totara,

OO is 1:76 scale, which places it almost exactly between HO (1:87) and S scale (1:64). The National Model Railroad Association recommends an initial weight of 1 ounces for an HO scale car, plus 1/2 ounces for each inch of body length.

For S scale, the NMRA recommends 2 ounces initial weight with 1/2 ounce per inch of body length.

So, we can extrapolate for OO scale an initial weight of 1.5 ounces plus 1/2 ounce per inch of length, a formula which I would tend to apply to rolling stock with two bogies. For shorter, two-axle rolling stock I would opt for the HO scale recommendation.

Hope this helpful,

Paul Schmidt
Contributing Editor
Trains.com