Model kit scales: Fraction, ratio, proportion??

[Nacho Z]

This may be a silly question, but it is something that has been bugging me for a while.  When stating the scale of a model kit in writing, is it 1/25 or 1:25?  I'm really hoping that someone can explain it to me in simple terms.  Also, is it a fraction, a ratio or maybe a proportion?  I doubt it is a proportion.  I have tried to Google it but didn't have much luck, probably because I didn't know how to ask the right question. Thanks!

Edited November 11, 2023 by Nacho Z
Typo

[Ace-Garageguy]

It's all the above.

1/25 expresses the idea that something is a 25th of the actual size...pronounced one-twenty-fifth.

Measure the real one, divide by 25. (The / in a fraction means "divided by")

1:25 expresses the exact same idea, but as a ratio, and is pronounced one-to-twenty-five.

For scale modeling, the terms can be used interchangeably. Both are correct, and mean the same thing.

Edited November 11, 2023 by Ace-Garageguy

[Nacho Z]

17 minutes ago, Ace-Garageguy said:

It's all the above.

1/25 expresses the idea that something is a 25th of the actual size...pronounced one-twenty-fifth.

Measure the real one, divide by 25. (The / in a fraction means "divided by")

1:25 expresses the exact same idea, but as a ratio, and is pronounced one-to-twenty-five.

For scale modeling, the terms can be used interchangeably. Both are correct, and mean the same thing.

 

I literally and honestly thought of you when I asked this question.  I have seen it written both ways on model kit boxes, ( / versus : ).  I would say, generally speaking, the Japanese kits have : instead of /.  Thank you, Bill, for answering the question.  I was hoping it was one or the other but I just couldn't figure out which way was the right way.

[stitchdup]

On older british boxes it sometimes just says 24 scale

[Ace-Garageguy]

11 minutes ago, stitchdup said:

On older british boxes it sometimes just says 24 scale

Where a lot of confusion can creep in with older kits is when they're labeled something like "1/4 inch scale", meaning of course 1/4 inch to the foot (1/48 scale in this case) but to some, it may as well be labeled

واحدة والثامنة والأربعون

Edited November 11, 2023 by Ace-Garageguy

[Can-Con]

10 minutes ago, Ace-Garageguy said:

Where a lot of confusion can creep in with older kits is when they're labeled something like "1/4 inch scale", meaning of course 1/4 inch to the foot (1/48 scale in this case) but to some, it may as well be labeled

واحدة والثامنة والأربعون

You don't see a lot of car kits in 1/48 scale, Bill.😉

[Ace-Garageguy]

5 minutes ago, Can-Con said:

You don't see a lot of car kits in 1/48 scale, Bill.😉

Believe it or not, there are kits of things other than cars.   

[Matt Bacon]

A thought… did anyone ever refer to 1/24 as 1/2” scale or half scale, like 1/4” or “quarter scale” once meant 1/48? I’ve never seen 1/72 referred to as 1/6” scale either. The 1/4” scale thing seems like a unique use. While we’re at it, 1/25 seems like a “metric” scale not an Imperial one, so why do US car models come in 1/25 instead of 1/24, when airplanes almost universally come in 1/48 (unless you count some very rare groove old Heller and Japanese kits in 1/50…)

best,

M.

[Ace-Garageguy]

41 minutes ago, Matt Bacon said:

A thought… did anyone ever refer to 1/24 as 1/2” scale or half scale like 1/4” or “quarter scale” once meant 1/48? I’ve never seen 1/72 referred to as 1/6” scale either. The 1/4” scale thing seems like a unique use. While we’re at it, 1/25 seems like a “metric” scale not an Imperial one, so why do US car models come in 1/25 instead of 1/24, when airplanes almost universally come in 1/48 (unless you count some very rare groove old Heller and Japanese kits in 1/50…)

Yes, there are old kits marked as 1/2" scale, 3/8" scale, etc. Look closely at the side of this box (fractional scale markings were very common on flying aircraft model kits as well).

Far as the 1/25 thing goes...American engineering drawings were primarily dimensioned in tenths of an inch, rather than in fractions (but architectural drawings were done in fractions...and I still have my old "engineer's scales" and "architect's scales" to prove it).   

     

Remember that many of the early US kits were directly derived from promos, themselves derived from factory drawings of American cars that would have been dimensioned in tenths. Converting to an easily calculated decimal dimension like 1/25 was easier than going to a fractional dimension. BUT...model companies that weren't in the promo biz routinely went with fractional scaling.

Edited November 11, 2023 by Ace-Garageguy

[peteski]

While likely not totally complete, this page is very helpful in listing what scales are used for what models.
https://en.wikipedia.org/wiki/List_of_scale_model_sizes

As for the usage of both "/" and ":", the slash is likely used to indicate division (as the dimensions of the full scale object divided by the scale number).  I think that is the original use and the colon became used later. Or maybe slash was used in British and American regions, while colon was used in Europe.

Edited November 12, 2023 by peteski

[peteski]

20 hours ago, Ace-Garageguy said:

Where a lot of confusion can creep in with older kits is when they're labeled something like "1/4 inch scale", meaning of course 1/4 inch to the foot (1/48 scale in this case) but to some, it may as well be labeled

واحدة والثامنة والأربعون

Bill, what language is that thing on the rigth, and what does it mean? Seems like something went wrong with copy/paste maybe.

[Ace-Garageguy]

22 minutes ago, peteski said:

Bill, what language is that thing on the rigth, and what does it mean? Seems like something went wrong with copy/paste maybe.

It's Arabic and it means "one forty-eight"...according to fpoogle translate.

Maybe I shooda used Swahili...      

moja arobaini na nane

Edited November 12, 2023 by Ace-Garageguy

[Can-Con]

18 minutes ago, peteski said:

Bill, what language is that thing on the rigth, and what does it mean? Seems like something went wrong with copy/paste maybe.

IIRC, it's Arabic, Peter.

[peteski]

1 hour ago, Ace-Garageguy said:

It's Arabic and it means "one forty-eight"...according to fpoogle translate.

Maybe I shooda used Swahili...      

moja arobaini na nane

Ah, and I was going to write "it's all Greek to me". 

Yeah, I know Greek alphabet looks different - it just a joke, just like Ace's post.

[Pete J.]

Personally, I prefer to express it as a ratio "x:y"  That keeps it straight in my head.  By the way, these ratios convert to metric with no conversion.  1:25 is one centimeter on the model equals 25 centimeters on the one-to-one

 

[bobthehobbyguy]

Here is a good link describing the differences.

 

https://www.difference.wiki/ratio-vs-proportion/

[peteski]

5 hours ago, bobthehobbyguy said:

Here is a good link describing the differences.

 

https://www.difference.wiki/ratio-vs-proportion/

I think we are getting mixed up here. 1/X and 2:X represent scale.  It can also be represented by a ratio, but if the 1:25 scale was to be represented by ratio, it would be 25:1 (as in 25 units of measure of a model represent 1 unit of the life-size object).

[Tom Geiger]

Here’s the NNL East 1/24 & 1/25 scale ruler.  We designed this tool and had a measuring device company print these for us on plastic. We gave them away in our Goody Bags, hoping to get more people interested in working in scale.

To make working in scale easier, we stuck to all inches. This way you don’t have to worry about inch to feet calculations.

The ruler works from the middle. That way it can be used for centering. I’m not home and this is the only photo on my phone. Here I was creating a truck bed from Evergreen plastic.  I needed a piece 58 scale inches wide and I used the centerline for orientation of how the pieces went together. 

A lot of folks just approximate, but why when you can work to exact scale?

Edited November 13, 2023 by Tom Geiger

[mk11]

[peteski]

Nice visual comparison of scales (using the same type of model), but limited, as there are many other modeling scales out there.