Why the factor of 8 in scaling?

[JollySipper]

Have you guys noticed this, or ever gave it much thought? In scaling down an automotive kit, it goes by a factor of 8. 1:1.... 1:8.... 1:16.... 1:24.... 1:32.... I'm wondering if this is intentional on the part of the kit makers?

[Ace-Garageguy]

20 minutes ago, JollySipper said:

...I'm wondering if this is intentional on the part of the kit makers?

Doubtful.

1/12 is a natural 1-inch-to-the-foot scale, but it's big. 1/24 is exactly half size, and more convenient for moderately priced kits.

1/8 is another natural, easy conversion from full scale, as 1/8" is a standard division of inches. 1/16 is just half the size of that, and 1/32 is just half again.

The "reason" we have these "factor of eight" scales is simply because of the standard divisions you find on an inch-system ruler.

1/10, on the other hand, is a common scale to work in as far as engineering goes, where many things are dimensioned with decimals.1/25 is an easier decimal conversion than 1/24, obviously.

[Snake45]

52 minutes ago, JollySipper said:

Have you guys noticed this, or ever gave it much thought? In scaling down an automotive kit, it goes by a factor of 8. 1:1.... 1:8.... 1:16.... 1:24.... 1:32.... I'm wondering if this is intentional on the part of the kit makers?

Other common "8 scales" in modeling include 1/48 (aircraft), 1/64 (Hot Wheels etc.), and 1/72 (aircraft and armor). 

[Bucky]

Makes me wonder where 1/35 scale and 1/43 scale came from.

[Vince Nemanic]

I remember reading that the pantogram machines that predated CNC machines had several reduction settings: 1 to 1,5; 1 to 2; 1 to 2.5;  and maybe others.  If the wooden master was made in 1/10 scale the pantogram machines would give 1/15. 1/20 and 1/25 scales or more. For 1/12 scale masters the pantogram gave 1/16,  1/24 and 1/30.  For 1/8 scale masters it gave 1/12, 1/16, or 1/20. I suspect there were several other settings for the machines as I doubt the manufacturers would make two different size masters.

I don't know where some of the other scales came from, but 1/43 is 'O gauge" for model railroading so that scale is to provide vehicles for train layouts.

One thing that always struck me as odd is that European and Japanese manufacturers use 1/24 where their countries use metric measures while American manufacturers use 1/25 and 1/20 which don't work well with the English system of measurement. 

[peteski]

Actually American O scale is 1:48.  I guess British 0 scale is 1:43.

See: https://en.wikipedia.org/wiki/List_of_scale_model_sizes

Edited August 3, 2020 by peteski

[niteowl7710]

7 hours ago, Bucky said:

Makes me wonder where 1/35 scale and 1/43 scale came from.

The story goes Tamiya chose 1/35 for their armor because it was the size required to house the motor and batteries for motorizing them and it just sorta stuck. 1/72 is the go to scale for Japan in modern days as even 1/35 & 1/48 prove to be to large for substantial collections in the tiny apartments many urban residents call home.

[Spottedlaurel]

9 hours ago, Vince Nemanic said:

One thing that always struck me as odd is that European and Japanese manufacturers use 1/24 where their countries use metric measures while American manufacturers use 1/25 and 1/20 which don't work well with the English system of measurement. 

I've pondered this one too over the years. For Britain, I suppose we only started going decimal on money and metric on measurements in the early '70s, by then Airfix and others were already doing their thing so they'd have stuck to an imperial scale.

It could be that other makers followed on and matched the scales made by the dominant kit manufacturers?

[Pete J.]

Being an old guy has some advantages in strange subjects like this.  When I was in college, drafting was a required course.  Now this was back when rudimentary computers filled a very large room and were fed punch cards and the computing time was "over night".  CAD was still decades away, but back to the story.  Long before plastic models, all designs were drawn on large pieces of paper by humans called draftsmen.

   Because you couldn't make a full sized drawing of something the size of the Titanic or a building, scale was invented.  Now the story is everyone had their own scale and  to get the huge rooms of draftsmen to all do things the same, they invented a standardized ruler called a "Scale".  These were triangular shaped rulers with each side having 4 different graduations on each side(each edge had one scale going from left to right and one going right to left. This allowed you to have 12 scales per ruler.  All drawings or "blue prints"  then had a legend in the corner that that stated the side of the rule used like 1"= 24" or 1/24 

 The rules came in two types.  An engineers scale and and architects scale.  The architects scale was in divisions of 12 to make it easier to design large things like buildings because at the time, large objects were build in feet and inches.  Engineers scales were broken down in divisions of 10 because most machine tools made small things that were calibrated in thousandths of an inch.   If you are interested, you can still buy these rulers from any drafting supply house or even amazon. They can still come in handy. 

  As to the metric scale, you could use an engineers scale which has 10 divisions but then the drawing itself would be done in inches, so they created a metric scale which was an engineers scale but the base dimension was a centimetre.  I hope some find this interesting. 

[Snake45]

12 hours ago, niteowl7710 said:

1/72 is the go to scale for Japan in modern days as even 1/35 & 1/48 prove to be to large for substantial collections in the tiny apartments many urban residents call home.

1/72 became a standard scale in WWII. The US government bought millions of ID or recognition models of airplanes. Kids and youth groups and so forth built them at first, then they were eventually molded/cast in solid pieces. The idea was these models, viewed at so many feet (I forget the exact numbers), looked just like the real airplanes seen at a mile or half a mile or whatever the number was. 

[Pete J.]

3 hours ago, Snake45 said:

1/72 became a standard scale in WWII. The US government bought millions of ID or recognition models of airplanes. Kids and youth groups and so forth built them at first, then they were eventually molded/cast in solid pieces. The idea was these models, viewed at so many feet (I forget the exact numbers), looked just like the real airplanes seen at a mile or half a mile or whatever the number was. 

110 inches.  5280' X 1.5 = 7,920'     7920 '/72 = 110"  or about 9 feet.  That would work well as a classroom teaching aid.  I seem to recall film of a class with the instructor up front flashing the models and the students responding. 

Edited August 4, 2020 by Pete J.

[Snake45]

40 minutes ago, Pete J. said:

110 inches.  5280' X 1.5 = 7,920'     7920 '/72 = 110"  or about 9 feet.  That would work well as a classroom teaching aid.  I seem to recall film of a class with the instructor up front flashing the models and the students responding. 

Last year on eBay I bought a like-new "official" US government-approved publication on how to build the models. I think it was published in 1942 or '43--all early war stuff. Apparently the book originally came with a set of full-size (1/72 scale) drawings but these seem to be very rare now. The book's still quite interesting--a real window into another time. 

[Ace-Garageguy]

3 hours ago, Snake45 said:

1/72 became a standard scale in WWII. The US government bought millions of ID or recognition models of airplanes. Kids and youth groups and so forth built them at first, then they were eventually molded/cast in solid pieces...

You should find this interesting...

 

[DonW]

On 8/4/2020 at 7:48 PM, Ace-Garageguy said:

You should find this interesting...

 

Really fascinating. But the Lancaster tail is totally out of kilter, the tail planes have a dihedral, not an anhedral and the fins and rudders are vertical. The man's a fool, but to be fair I didn't listen to the dialogue so he may have explained just that.

Thanks for posting. I love that kind of model, you can pick it up and enjoy it. And it looks good from a distance (except the Lanc).

[Pete J.]

2 hours ago, DonW said:

Really fascinating. But the Lancaster tail is totally out of kilter, the tail planes have a dihedral, not an anhedral and the fins and rudders are vertical. The man's a fool, but to be fair I didn't listen to the dialogue so he may have explained just that.

Thanks for posting. I love that kind of model, you can pick it up and enjoy it. And it looks good from a distance (except the Lanc).

Don, these are not models he built.  They are cast pieces created for recognition classes in the military and were collected by his grandfather.  As such they are quite old and knowing how early rubber/plastic ages, they have probably warped badly and are damaged.  I would bet the Lancaster is 80 or more years old so depending on how they have been stored it is even lucky to be around.   They are collectible as WWII and Cold war military items. 

[Brian Austin]

On 8/3/2020 at 4:54 PM, peteski said:

Actually American O scale is 1:48.  I guess British 0 scale is 1:43.

See: https://en.wikipedia.org/wiki/List_of_scale_model_sizes

Correct, British O Scale is 1:43, or "7mm Scale".  HO is directly half of that.  Note though that at least one line of vintage British diecast vehicles (Spot-On) was said to be scaled at 1:42 for whatever reason.  Many other brands such as Corgi were "box scaled" with some cars being scaled at 1:48 or 1:50 instead of 1:43.

American O was standardized at 1:48 scale for convenience to those using rulers, but in the mid 20th Century there was some model railroad equipment manufactured in the slightly unwieldy scale of 17/64" to the foot to be a bit more accurate in relation to the 1.25" track gauge.

 

Continental European O Scale is scaled at around 1:45.

 

Finally, note that the "O" should in fact be a zero instead of a letter.  The next-largest track size in the toy train catalog is #1, and if you double European O Scale you get 1:22.5, garden railway size.

[peteski]

1 minute ago, Brian Austin said:

 

Finally, note that the "O" should in fact be a zero instead of a letter.  The next-largest track size in the toy train catalog is #1, and if you double European O Scale you get 1:22.5, garden railway size.

Exactly, that is why in my post I user "oh" in the American context, and "zero" in the Britis context.  While it is a "zero" gauge, Americans chose to represent it with an uppercase "oh".  I tried to explain that on a U.S. model RR forum I frequent, but it is a losing battle.

[DonW]

9 hours ago, Pete J. said:

Don, these are not models he built.  They are cast pieces created for recognition classes in the military and were collected by his grandfather.  As such they are quite old and knowing how early rubber/plastic ages, they have probably warped badly and are damaged.  I would bet the Lancaster is 80 or more years old so depending on how they have been stored it is even lucky to be around.   They are collectible as WWII and Cold war military items. 

Thanks for explaining that Pete, I take back my comment. Shame about the Lanc nonetheless. I loved the rest of the collection.

[Ace-Garageguy]

12 hours ago, peteski said:

...I tried to explain that on a U.S. model RR forum I frequent, but it is a losing battle.

Explaining reality usually is these days.

[Brian Austin]

Interestingly, along with HO came 00, and later even 000 (close to the present N Scale) which followed the precedent of paint brush cataloguing:  smaller sizes got progressively more zeros.  Neater from the standpoint of promoting the hobby as a whole, but manufacturers introduced new scales at random moments in time, inventing their own  designation for them in their marketing.  Surely messy for a beginner, but I recall some good books on the subject from the '70s and '80s that explained all this pretty well.

 

Perhaps we should refer to "0" as Naught Scale.  Or Null, or, Zilch or Nada or...