Blue prints

~J~ · 21 Sep 2006 at 23:16

Bit of a stab in the dark (tried google and wikipedia).

Anyone old enough (or young

) to remember the 'proper' blueprints that were used up until the mid-80's?

I'm talking about the ones that came on quite thick sheets (probably A1 size) paper, and absolutely stank of chemicals.

If you do, don't suppose you know the technical details such as how they were made (I think it was the paper wrapped around a tube which was placed over an argon lamp or something) and what caused the smell (was it cobalt?).

Sorry, totally obscure I know but hey, y'never know!!

Cybermyk · 21 Sep 2006 at 23:29

My mother used to print them out for ICI engineers up to the early 80's.

Useful link

Psymonkee · 21 Sep 2006 at 23:30

Actually I think I might be able to help you

Came across some scrubs behind the scenes stuff which had a section on making blue prints for set designs and I seem to recall a very similar method

~J~ · 21 Sep 2006 at 23:31

Cybermyk said:
My mother used to print them out for ICI engineers up to the early 80's.

Useful link

Absolutely perfect! Cheers for that, really appreciate it.

Brizzles · 21 Sep 2006 at 23:32

I'm a bit rusty on the subject , but here goes.

My understanding is that, a Blueprint is a type of print used for copying engineering drawings and similar material. The name is popularly applied to two separate methods, more exactly designated as the blueprint and the whiteprint, or diazotype. In blueprinting, the older method, the drawing to be copied, made on translucent tracing cloth or paper, is placed in contact with paper sensitized with a mixture of ferric ammonium citrate and potassium ferricyanide, which is then exposed to light. In the areas of the sensitized paper not obscured by the lines of the drawing, the light reduces the ferric salt to the ferrous state, in which it reacts with the potassium ferricyanide to form insoluble prussian blue. The exposed paper is then washed in water, producing a negative in which the lines of the drawing appear in white against a dark blue background.

In the whiteprinting method, the paper is sensitized with a mixture of a diazonium salt, a coupler that reacts with the diazonium salt to form an azo dye, and an acid that prevents coupling. Exposure to light destroys the diazonium salt. Final treatment with an alkaline agent, such as ammonia gas, neutralizes the acid, thereby bringing about the coupling reaction. Because it produces dark lines on a “white” or light background, whiteprinting has become the favoured method.

Hope this helps.

Mark.

( O.K. i found it on the Interweb

)

~J~ · 21 Sep 2006 at 23:35

Cheers fellas, got enought to work with now, at least I've got some keywords in there to research a bit more.

Pint in the post.

Brain · 21 Sep 2006 at 23:55

blue prints do stink a bit though dont they. Ive got a full set of them in a tube somewhere...

a bit sad to admit what they are but what the hey...

...original blueprints of the USS Enterprise-D from Star Trek. I got a copy from the guy who came up with the 'original' blueprints before they were used somewhat illigitamatley by paramount whilst not giving full credit to the this guy who came up with the idea for they type of drawing (or so i remember...i would need to dig the whole set out which includes explanations and cross-sectional views of ALL decks)...

fin