blue prints and scale

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tippie53
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Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
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blue prints and scale

Post by tippie53 »

There is a thread on another forum and I want to clear a few things up here so we don't have the same issue.

Many assume a blue print is a scale drawing. This is in fact wrong. A blue print unless marked as a full scale drawing is at best a representational view. That means the drawing may be somewhat to shape but not to scale so use the numbers to understand what you are doing.
Also if you look there is a scale as 1/4 in = 5 feet.

I was trained as a machinist and engineer and this information may help you as a builder to be more accurate.
Know your source

Also when a drawing is made in shops a print was never copied , we used a plotter , this is a printer that essentially draws the print. A copier will copy but it will loose some accuracy in the copy process. In a plotter the paper is securely held and moves under the pens or they may move but the paper is controlled and in a copy it is just a different process that doesn't need the accuracy .
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
nkwak
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Joined: Sat Nov 13, 2010 9:55 pm
Location: Pittsburgh PA suburbs

Re: blue prints and scale

Post by nkwak »

Thanks, John. I found that copiers are indeed not accurate when I did so with some plans at Kinko's. I found myself poring over the numbers instead and double checking them when building my forms. It added time to the process and frequently killed any sense of progress I was making in the project.
~ Neil
ruby@magpage.com
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Joined: Thu May 24, 2012 8:03 am
Location: Chestertown Maryland

Re: blue prints and scale

Post by ruby@magpage.com »

A copier will reduce the image, the one I have by 1% or so. Even with a scale drawing, after 4-5 copies, not only does the image get hazy, you might be substantially different in size.

Ed
Ed M
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