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Can anyone inform me as to what enlargement setting would be neccesary to enlarge a set of plans from 1:48 scale to 1:20.3 scale. I looked up on the old web and found that from 1:48 to 1:24 it is 200% and that sounds right but what about 1:20.3 ? And if anyone can enlighten me as to the formula for figuring this out, I will keep it handy.
Thanks,
Mike Anderson
 

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Flip out your handy calculator...

48/24*100 is 200

48/20.3*100 is 236.45

And it works for any scale you want:

48/29*100 is 165.51
 

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A little different way than what you are refering about, what I do is take a scale provided by a company called The Railscale, if the plans are in HO scale I measure the plans
or the building with a HO scale ruler and then use my prefered scale 1:22.5 to layout my new measurements, I got the scale that has HO on one side and 1:22.5 on the
other so there is less fumbling around. It works good for me. There webb site is www.therailscale.com
Dennis
 

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HO is 1/87

87/22.5*100 = 387%
 

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As a side note to the above, most copiers will not enlarge past 200% ( ie 2x). When this occurs, you need to make an initial copy at a lower setting below 200%, then enlarge that copy to get to the final percentage needed. As an example, for your case you need 236.45% which means that you want to enlarge it 2.3645 times the orignal. A little math shows that 1.5376 (153.76%) time 1.5376 equals 2.3642. Thus, set your copier at 154%, and make you first copy of what you need. Then place that copy on the copier and copy it again at 154%. The second copy will be roughly 236% larger than the original. Also note that the two numbers do not have to be the same, as long as they multiply to the final number that you need. Thus, you could use 1.4 x 1.6889 = 2.3645 or 140% first copy, 169% second copy. Or you can do the same in three copies using smaller numbers. If you need more help, email.

Randy
 

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Head off to Fed Ex Kinkos. They have a drum copier that will handle and print any material that will fit on up to a standard size 5 drawing high by any length as the print paper is a roll. I have used them many times. Their staff is most helpful. Chuck
 

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I used to live a few miles away from a particularly beautiful train station in Perris CA. This Queen Anne beauty was featured on the cover of a book I found and inside was the plans for it's construction! Sadly, the instructions were in HO scale! I'd love to have that station on my layout. An e-mail has been sent to you about your software, Stan.
 

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This is how I resize drawings..works great! :)
but you need a good photo program to do it (something that can measure,in inches or Centimeters or some real unit.)


It sounds complicated!
but its dead-easy once you get it down..

its much more complicated to explain it that it is to actually do it! ;)


Scan the original drawing..doesnt matter what size or scale it is..

scan it at a good ppi, like 200 or 300 ppi.

Bring the scan into your program (I use photoshop)

measure the entire width of the scan, from edge to edge..
lets say its a HO scale drawing of a locomotive and the original drawing is on a 8x10 sheet of paper..

so the total width of the scan is 10 inches. (completely ignoring the drawing at this point..
you only care about the total width of the piece of paper the drawing is on)


Now take one known prototype dimension..lets say the wheelbase of the prototype engine is 60 feet.

60 feet X 12 = 720"

measure the actual distance on the drawing for the loco wheelbase..if its HO scale it would be 8.27"


Now you take the scale you want to convert the drawing to..lets say 1/29 scale.
720 prototype inches divided by 29 = 24.82" - thats how long the loco wheelbase should be in 1/29 scale.


So, you have a drawing where the length of the wheelbase is 8.27" (HO scale)
you want to make a drawing where the wheelbase is 24.82" (1/29 scale)

using those two dimensions, plus the overall width of the paper (10 inches) the formula is simple:

10 X

----- = -----

8.27 24.82


Solve for X

10 X 24.82 = 248.2

248.2 divided by 8.27 = 30.01

X=30


Resize the whole drawing to 30" wide.

done!

print out at 100%

you know have a drawing of the loco in 1/29 scale..

This works for any size original drawing, and converting to any scale..

you only need three numbers, and solve for the fourth..
the fourth is the length of the final drawing.


Scot
 

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Here's another option, buy any one of the RailDriver Cyclopedias and along with it you also get their Scale Print utility program. All you have to is one dimension set the two points and specify the known distance and set the scale you want it printed at, if it winds up being larger than the default 8.5" x 11" paper it will break it down and print the drawing on multiple pages that have alignment marks.
 

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One great place to have those enlargements made is your local drafting shop. They have the supplies and copiers for those large pages. After all, Blueprints, that is to say ammonia copies, are no longer used. Now CAD is the thing and they just use a very large copier or plotter to do the printing. They can do what is being discussed here and probably for a competitive price too!
 

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Another detail that will evade my frontal lobe when needed, therefore ...

You can enter up to 10 item's description and size.
Has most of the traditional modelling scales.
Works from scale to scale, prototype to scale and vice versa.
Displays the percentage for photocopying etc.
Best of all - It costs nothing !

http://locobuilder.com/scale_conversion_calc.htm

Andrew
 
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