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General Aircraft: Tips & Techniques
Discussions on specific A/C building techniques.
Questions on calculating scales to mm/inches
New Hampshire, United States
Joined: June 06, 2002
KitMaker: 1,225 posts
AeroScale: 55 posts
Posted: Saturday, January 28, 2012 - 11:16 PM UTC
Ok I know I'm most likely beating a dead horse here,(figurtively),but I still have not grabbed the concept on how to calculate mm to inches in different scales.
I'm now working on a diorama of a aircraft carrier elevator that will be in 1/200th scale.There was a fellow modeler sometime ago that did the same in I believe 1/48th or 1/32nd.Any how the deck part of the elevator was 1mm thick and 30x32cm overall surface size,I beams were 9.5mm in height,and the bulk heads where 18.3x3.2cm long based on what little notes I have from an article on this modeler.
So now I would like to know is there an easy formula or equation in trying to scale these numbers down to the 1/200th scale?
Staff MemberAssociate Editor
Victoria, Australia
Joined: June 09, 2009
KitMaker: 8,156 posts
AeroScale: 3,756 posts
Posted: Saturday, January 28, 2012 - 11:30 PM UTC
Hi Jody.

Firstly you will need to confirm the scale. If we assume the scale is 1/48th, then you just need to take the dimension, multiply by 48 to get the original 1:1 measurement, then divide by 200 to get your scale measurement in 1/200.

To convert mm to inches, divide the measure in mm by 25.4 to get the equivalent in inches.

Hope this makes sense.

Cheers, D
Queensland, Australia
Joined: July 10, 2011
KitMaker: 653 posts
AeroScale: 165 posts
Posted: Saturday, January 28, 2012 - 11:35 PM UTC
Easiest way to do the calcs is to convert back to full scale

1/48 scale 30 x 32 x .1 (1mm = 0.1cm)
Multiply by 48 becomes 1440cm x 1536cm x 4.8cm
similarly 18.3 x 3.2 becomes 878.4cm x 153.6cm
9.5mm = .95cm = 45.6cm (fullsize)

so to convert those to 1/200 simply divide by 200
so 1440 x 1536 x 4.8 becomes 7.2cm x 7.68cm x 0.024cm

Convert to inches 1" = 2.54cm so divide by 2.54
So we get 2.835" x 3.023" x 0.08"

Does that help?

Oh I now see Reg got in first... ah well
Croatia Hrvatska
Joined: November 06, 2009
KitMaker: 624 posts
AeroScale: 609 posts
Posted: Sunday, January 29, 2012 - 02:17 AM UTC
Hi, Jody!

First of all, welcome aboard! If you are interested, please send me PM, and I will forward you small software that you can use on your PC (scale converter) that does everything for you. Inches to mm, scale to scale, and many other functions as well. This also applies to other interested parties as well

All the best,
England - North East, United Kingdom
Joined: November 18, 2006
KitMaker: 2,828 posts
AeroScale: 1,720 posts
Posted: Sunday, January 29, 2012 - 05:06 AM UTC
I normally use this scale conversion tool.

Online Scale Conversion Tool