# Weight Question



## Old Bill (Nov 28, 2013)

I understand the reason for adding weight to locos. and cars.
But is there a base guide line or is it hit or miss as to the amount
of weight to add.


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## Gansett (Apr 8, 2011)

This should help you.

http://www.nmra.org/standards/sandrp/rp-20_1.html


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## Old Bill (Nov 28, 2013)

JackC
Thank you


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## MtRR75 (Nov 27, 2013)

The new URL for the car weight recommended practice is:

http://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-20.1.pdf


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## Fire21 (Mar 9, 2014)

MtRR75 said:


> The new URL for the car weight recommended practice is:
> 
> http://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-20.1.pdf


I have a question:  If the initial weight of a car is different from what this chart shows, should we still add the suggested amount of weight? What does that do to the optimum weight that the chart talks about?

Seems to me this chart would work only for those cars that meet the initial weight listed. :dunno:


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## mopac (Feb 24, 2011)

Initial weight of car has nothing to do with the chart. Go by the chart.

Example - HO - 6" car - 1 oz plus 3 oz for 6" - 4oz total for a 6" car properly
weighted. Of coarse initial car weight figures in to the 4 oz total. Just add enough weight to
get car to a total of 4 oz (for 6" car).


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## Fire21 (Mar 9, 2014)

Thanks!


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## flyboy2610 (Jan 20, 2010)

And remember, when adding weight keep it low. Otherwise the center of gravity will rise on the car and it could become rather tippy.


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## Fire21 (Mar 9, 2014)

Yessir, I understand that aspect. Thank you!


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## mopac (Feb 24, 2011)

I think the nmra standard is really heavy. 6" car would be 1/4 pound. 20 cars
would be 5 lbs. Point being it will be a lot more drag on the engine. Where they
call for 4oz I do 3oz. Maybe 1 oz less than the standard calls for. I think a BB
car is around 1 to 1 1/2 oz out of the kit.


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## MtRR75 (Nov 27, 2013)

Remember that the weight guidelines are a "recommended practice", not a "standard". The text accompanying the table clearly acknowledges that good quality track will not require cars to be this heavy. But following the table will decrease the chances of derailments on less-than-perfect track.

In general, I don't worry about the guidelines. Most of my cars are somewhat underweight. If a car starts derailing, I can usually find the cause without adding weight. But if a car is clearly lighter than others in the consist, I will add some weight.


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