Scale conversion for trailer lengthing?

[JRJ]

I have a 40ft that I want to do a 53' or 48' how much do I need to add and is there a formula for it?

[J Smith]

http://www.briansmodelcars.com/tools/calculator-scale.asp

This is what I use

[Jim B]

Ok, that's going in the Favorites!

[JRJ]

Perfect!! Just what I was looking for,Thanks.

[Truck parts]

I also want to say Thank you for that site.

[Chad]

For a 40' 1/25 scale trailer to be turned into a 48' the overall length will be 23.04". I just did two flatbeds.

Chad