Large Scale Central

changing scale on build plans

I have a drawing that is in O scale (1/48). I want to change it to 1/24. Someone explained how to do this once to me well… I forgot it… Anyone’s help is appreciated…

Enlarge it by a factor of x2. Or, if you don’t have the facility to do that either at home or in a local store or library, just multiply every measurement on the drawing by 2.

tac

With a calculator, you can do ANYTHING.

Oh. I forget that 5 out of 4 people don’t understand fractions.

Divide the starting scale by the desired scale to get the ratio between the two. In this case, 1/48 */. 1/24. To simplify, you can invert the scales, so you have 48 */. 24 = 2. If your drawing was in HO scale (1:87) and your desired scale was 1:29, you’d have 87 */. 29 = 3. If your drawing is S scale (1:64) and your desired scale is 1:20.3, you’d have 64 */. 20.3 = 3.15. If you’re making enlargements on a copier, 2 = 200%, 3 = 300%, 3.15 = 315%.

You may want to check out Stan Silverman’s “Handy Converter” software. You can convert between scales and also print out scale rulers in a variety of scales.

Later,

K

The other option is to leave it as is. Use an “O” scale ruler (1/48) to measure the dimensions in scale feet off of the plans. Use a 1/24 ruler to mark the scale feet on your model.

Bruce Chandler said:

The other option is to leave it as is. Use an “O” scale ruler (1/48) to measure the dimensions in scale feet off of the plans. Use a 1/24 ruler to mark the scale feet on your model.

Bruce, that’s too easy. We demand to do it the hard way. And if we can roll in Common Core math, so much the better. (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-foot-in-mouth.gif)

Being a dork, I am of the opinion that notwithstanding the number of mathematical genii represented here, my method of simply enlarging the plan by TWO or MULTIPLYING every MEASURED dimension by TWO is the simplest by far. Multiplying any figure by TWO is surely not beyond the wit of anybody on these pages, is it?

Right now, I’m building a South African narrow gauge caboose without any plans at all, just a couple of photographs on the internet and using the known gauge of the rails on which it is standing.

tac ‘a man with the body of a genius and the brain of an athlete…’

Well, I took some HO plans to Kinkos, and told the guy I needed them enlarged so the item in question was a certain dimension. He scanned the plans into his computer, clicked a few buttons, and they printed out, spot on the size I wanted. Of course I was taking HO plans and making them 1:29, so it was simple to have them printed at 300%.

Changing scales is easy. You have two scales involved, known and desired. In this case, the known scale is 48 (1:48). The desired scale is 24 (1:24). Known scale divided by desired scale is the factor required to change the know scale to the desired scale. So… Known scale - 48 - divided by desired scale -24 - equals 2. Lets to a more interesting one. We have drawings in HO (1:87) and we want to go to Aristo scale (1:29), therefore 87/29=3. How about ‘O’ scale to ‘N’ scale, 48/160=0.3.

Easy, peasy…

Someday I will learn to spell…

Bob, I aint learned how to spell yet, that’s what a spell chequer is for. Now if only they would make a dyslexia checker I would be all set.

tac Foley said:

Being a dork, I am of the opinion that notwithstanding the number of mathematical genii represented here, my method of simply enlarging the plan by TWO or MULTIPLYING every MEASURED dimension by TWO is the simplest by far. Multiplying any figure by TWO is surely not beyond the wit of anybody on these pages, is it?

Right now, I’m building a South African narrow gauge caboose without any plans at all, just a couple of photographs on the internet and using the known gauge of the rails on which it is standing.

tac ‘a man with the body of a genius and the brain of an athlete…’

Tac,

your way is easy. . . that’s why its being rejected. Its no fun to just simply multiply by two. Common core math that is so much better requires at least another 50 steps for it to be right. Thats why kids have to wait until they get to high school now in order to do multiplication.

Thanks for all of the help guys. Appreciate it.