# Changing scale drawings



## Lost Lumber RR (Aug 24, 2021)

Does anyone know what I would have to do to upscale 1:48 scale plans to 1:20.3? Other than that, does anyone know where I can find 1:20 scale plans for buildings, water tanks, coaling stations, etc?


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## Ironton (Jan 2, 2008)

Changing scale is a mathematically simple thing. You multiply each measurement by a ratio found by dividing the given scale by the desired scale. In your case that would be 48 divided by 20.3 or 2.364532.

An alternative would be to take the plans to a copy service and have them blow the plans up by the calculated ratio. Then you would have a set at the desired scale which you could take the measurements off of directly. Let's not go into copying distortions, they are minor and only for the rivet counters.


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## DetailsDetails (Jul 28, 2021)

I second the copy service idea. 
Though copy services can be off by a percent or 2, depending on the process used.
Similar to what Ironton described, you can find a picture of a non-dimendioned drawing of equipment or structure. Use a known dimension and scale it with a copy service using that multiplier.
So. You find a drawing in an old MR magazine or a book. 
You might know how big the footprint of the building is. Or how long the overall length of the equipment. In a pinch you could use the size of a doorway. 
This can help you figure out the multiplier with which to enlarge the drawing you found


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## Pete Thornton (Jan 2, 2008)

There's a "Scaleprint" utility available. It takes your drawing, you set the scale and tell it a known dimension (e.g. the length of the wall,) and it scales the drawing to print it. It even works over multiple pages, leaving a margin but inserting alignment marks. 
RailDriver | Scale Print Utility


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## Lost Lumber RR (Aug 24, 2021)

Thanks for the responses. At one point in time, I knew how to do that. Must have a case of CRS.


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## rhands (Jun 5, 2014)

Lost Lumber RR said:


> Does anyone know what I would have to do to upscale 1:48 scale plans to 1:20.3? Other than that, does anyone know where I can find 1:20 scale plans for buildings, water tanks, coaling stations, etc?





Lost Lumber RR said:


> Does anyone know what I would have to do to upscale 1:48 scale plans to 1:20.3? Other than that, does anyone know where I can find 1:20 scale plans for buildings, water tanks, coaling stations, etc?





Lost Lumber RR said:


> Thanks for the responses. At one point in time, I knew how to do that. Must have a case of CRS.


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## rhands (Jun 5, 2014)

I have purchased on ebay g scale plans for buildings, search for g scale, 1:24, or 1:20


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## manimal (May 25, 2009)

I use Stan's handy converter. Even if I do the math in my head, its comforting to see the app give me the same result. If you use the any scale to another calculator it gives you the copier setting too. Well worth the $20 Handy Converter


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## Railroad Pony (11 mo ago)

If the copies are a bit off, find a known dimention and the copier place can correct up or down into it. I've had this done on H.O. plans I reduced to N scale.


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