Offset Printing Tips
Offset papers play an integral part in your communications plans. With the economy it affords you in producing letterheads, newsletters, fliers, etc. - we wanted to give you something more. We have compiled a few valuable suggestions to enable you to plan and print more successfully. Williamsburg Offset, a more perfect union between paper and printer.
| Make Ready Ink Density Line Screens Climatizing Drying Performance |
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Make Ready
The surface of Williamsburg Offset has been designated to be uniform top to bottom (felt to wire). However, it is advisable to load 50-100 sheets upside down to see what differences, if any, you might experience when printing both sides of the sheet. This helps plan for any ink density changes that might be needed from side to side.
Ink Density
To achieve the best results when printing Williamsburg Offset, if is suggested that you keep total ink density to 265%. This will provide excellent blacks without setoff or other press related issues. Proper ink densities are also important when printing Williamsburg Offset on either web or sheetfed. It is advisable to subtract the density of the paper (ink density minus paper density) while the surface smoothness can after ink density settings, a good starting point for the best results should be:
Black: Suggested ink density on press/1.25 (with 25% total expected dot gain).
Cyan: Suggested ink density on press/1.00 (with 24% total expected dot gain).
Magenta: Suggested ink density on press/1.12 (with 25% total expected dot gain).
Yellow: Suggested ink density on press/ .95 (with 23% total expected dot gain).
Line Screens
While total ink coverage is important, it is equally important to use the proper line screen to provide crisp and clear images. We suggest using 150-175 line screens (with curve adjustments) for Williamsburg Offset Smooth Finish. This will provide clearer images with minimal dot gain. The use of 133-150 line screens is a good rule when using Williamsburg Offset, Vellum finish. You will also be able to print using stochastic screens without any problems.
Climatizing
Since the drying times throughout the year fluctuate, it is advisable to bring the paper into the pressroom 24 hours before the stock will go through the press to help acclimate it with the environment. This will help eliminate instances of curl when on press.
Drying
For quicker turn-around times for sheetfed runs or when a job calls for high ink coverage, it is best to use low-solvent ink. This will provide quicker drying times. A good ground blanket will also provide the best surface for printing with a minimum amount of wash-up.
Performance
Williamsburg has been engineered to run clean, and the use of good ground buffed blankets, will give the best overall print and press performance. When running Williamsburg Offset on headset webs, it is always advisable to take the silicone out and run water plus an anti-static solution. It is also a good ideal to turn the coated up to help keep moisture in the sheet when using heavier weights. This will minimize any potential static or cracking at the fold as the sheet moves into a folder or sheeter.