Nominal Pipe Sizes – scaled Prototype to O, S, HO, N, Z is a free Model Railroad Discussion Forum and photo gallery. We cover all scales and sizes of model railroads. Whether you're a master model railroader or just getting started, you'll find something of interest here.


This may prove useful .. you can either ..

1 - look down the left column and find the NPS (Nominal Pipe Size) .. the follow the row to the right under your scale and find the size wire/tubing to represent that pipe.

2 - Follow the column for your scale down to the size that matches the wire/tubing you have .. then slide over to the left to find that actual prototype pipe that will represent.

Nominal Pipe Sizes – scaled Prototype to O, S, HO, N, Z


Good Link, thanks for posting:)

JP. Thanks. I would like to say that it is totally from the 'goodness of my heart' .. but to be honest I found myself looking up pipe sizes .. grabbing a calculator ... etc. .. so I said to myself .. ".. self .. let the spreadsheet do the work .. and when everything is 'happy' .. export to a pdf .." .....


Bob Hayes
eTraxx (self) you said a good thing to yourself. That will come in mighty handy and I have bookmarked it. Thank you


Cheap doesn't mean bad. I figure use whatever works. I need to start looking at the coffee stirring 'straws' you see sometimes .. like miniature straws .. need to grab some next time.

Here is a link to an interesting article. The website is a paper modeler's forum. (have a TON of good into there for scratchbuilding). The article shows how to roll small tubing from paper .. they show a 2mm dia tube


That is a 4 1/2" pipe in HO (nominal OD 4.5") .....

Want something smaller? How about 1mm?

THIS article shows how. Crazy. That is a 2" pipe in HO (nominal OD 2.375")

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