Joined

·
902 Posts

In my mind if I'm using a scale of 3/4" per foot, and I have a 1 foot long real world object the model of it would be 3/4" long. 16 of these 3/4" models end to end would measure a total of 1 foot long.

1 - 9 of 9 Posts

Joined

·
902 Posts

In my mind if I'm using a scale of 3/4" per foot, and I have a 1 foot long real world object the model of it would be 3/4" long. 16 of these 3/4" models end to end would measure a total of 1 foot long.

You are correct.

3/4" = 1' is 1/16th scale.

1/18th scale is 2/3" = 1'.

3/4" = 1' is 1/16th scale.

1/18th scale is 2/3" = 1'.

Joined

·
902 Posts

Joined

·
12,221 Posts

Joined

·
287 Posts

COMING FROM THE PROFESSIONAL DRAFTING ARENA...What scale is 3/4 inch per foot? Some say it's 1/18th scale and I say it should be called 1/16th scale, since there is a 1:16 ratio between 0.75" and 12".

In my mind if I'm using a scale of 3/4" per foot, and I have a 1 foot long real world object the model of it would be 3/4" long. 16 of these 3/4" models end to end would measure a total of 1 foot long.

Yet someone told me for 1/18th scale if you have a 6 foot object you are modeling you would multiply 3/4 times 6 and get 4.5 inches. Ok, but in reverse if I take 6 feet and convert to 72 inches and divide by 18 (which should be 1/18th the original size) you get 4 inches and not 4.5 inches! This is a paradox for me.

When scaling down something measured in feet to inches, aren't you supposed to keep the units the same during the math calculation, for example you should convert feet to inches to scale inches to inches and not feet directly to inches, right?

WHEN ALL ELSE FAILS, DO THEY MATH...

SCALES ARE RATIOS

12/.75=16

Joined

·
902 Posts

A/a = B/?

gets you:

? = aB/A

You would say it like; A is to a as B is to ?

Or you could do A is to B as a is to ? like this:

A/B = a/? and you cross multiply and get ? = aB/A

You see it's the same.

Joined

·
31,461 Posts

Well, since a scale IS a ratio, yeah....

Joined

·
12,221 Posts

Yeah, I can see it now.Yet someone told me for 1/18th scale if you have a 6 foot object you are modeling you would multiply 3/4 times 6 and get 4.5 inches. Ok, but in reverse if I take 6 feet and convert to 72 inches and divide by 18 (which should be 1/18th the original size) you get 4 inches and not 4.5 inches! This is a paradox for me.

When scaling down something measured in feet to inches, aren't you supposed to keep the units the same during the math calculation, for example you should convert feet to inches to scale inches to inches and not feet directly to inches, right?

3/4" per foot is 1/16th since 12"/.75"=16. Your friend's not converting feet to inches resulted in an error of 2" for every 12" which made it appear to be 1/18th instead of 1/16th.

Joined

·
902 Posts

Delete

1 - 9 of 9 Posts

- This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.

Hobbyist Forums

A forum community dedicated to all Hobbyists. Come join the discussion about die cast, models, slot cars, radio control vehicles, classifieds, swaps, and more!

Full Forum Listing
Recommended Communities

Join now to ask and comment!