A blueprint copier is a copy machine that is specially designed to take on large or oversized projects, especially those, like blueprints, that are light-sensitive. Standard photocopying works really well for most documents and books, though machines have natural limitations when it comes to the size of material that can be both scanned and printed. Blueprints are an example of documents that don’t work well in this sort of machine; photo negatives and proofs are another. It’s not just size that makes blueprints hard to copy, though most are quite large. They’re usually drawn on transparent paper that creates strange shadows and streaks when copied using standard mechanisms. Copiers designed for these sorts of materials use different lights and usually often have a vacuum suction mechanism to allow for unbroken contact with the surface. In some places it’s also possible to buy specialized machines that double as copiers and light tables, which allows for quick and easy proofing. No matter their specifics, blueprint copiers tend to be quite expensive both to buy and to operate, and they usually take up a lot of space.
Blueprint Basics
Above all, this sort of copier is made to deal with blueprints. Blueprints are the standard way of drafting large construction and architectural drawings, and they’re used by architects and designers all over the world. The prints are more than just drawings, though; in most cases they’re actual plans or “maps” to guide a construction project. They are usually drawn on large sheets of translucent paper that can easily be traced or pinned above other existing plans to give drafters a sense of important overlaps. Copying them precisely is often important so that various members of a construction or architectural team are working with identical copies. Discrepancies in angle measurements or sizing considerations can be disastrous for a building.
Regular copiers don’t work for more reasons than just the blueprints’ size. The process of creating a blueprint is somewhat complex in most cases. Once the design has been traced or drafted, it is then placed against paper that has been sensitized with ferric ammonium citrate and potassium ferricyanide, which is then exposed to light. The areas on the sensitized paper that are not covered by the drawing are changed to blue as the light causes a chemical reaction between the two chemicals. This is how the prints get their name, and also makes them more or less impossible to reproduce with a standard light-based copier.
Achieving Full Contact
A blueprint copier can be used to expose pin graphics and to draft overlays. It can also be used for light sensitive screens, film negatives or positives, and sepia prints. This type of copier uses a vacuum system to ensure full contact with the item being copied. This is important because it can be difficult to keep larger copies still as they feed through the blueprint copier. If the original does not stay still, the copy will be blurred.
Advantages for Light-Sensitive Materials
These sorts of copiers can usually handle a wide range of light-sensitive materials, and as such there are usually several different types of copiers available. Choosing the right one is often a question of understanding the specifics of the materials that are most likely to be copied. Machines typically use eighteen fluorescent lamps at 65 watts each for exposures, and they also generally contain four cool white lamps at 40 watts each. They usually have a power switch and mode switch, and a timer to control exposure time and heat distribution.
Light Table Combination Units
It is sometimes also possible to acquire a copier that doubles as a light table and has a preview top. In most cases this type of copier is made only for exposing media and requires a separate developing system if prints are to be created on site. Some are also capable of sending digital images, usually over a secure Internet connection.
Price and Space Considerations
As could be suspected given the large size of most blueprints, the copiers designed to accommodate them tend to also be quite big. They are normally best suited for open offices, or else their own dedicated rooms. In most cases they are quite expensive; additionally, the materials needed to keep them operational — the specialty paper, bulbs, and inks — can be pricey, too. As such, it’s usually only large architectural firms or specialty copy companies that purchase and own them. Smaller operations often outsource their copying to contractors.