How to Prepare Print Files for Packaging Products

Custom packaging starts as a flat, diecut sheet, so the file you upload has to line up with the dieline before we print, score, and ship it. Build your artwork in CMYK on the 4OVER4.COM packaging template for your box, keep important text and logos inside the safe area, and save a print-ready PDF at 300 DPI. Get those basics right and the printed box folds up clean every time.

This guide walks through the parts people miss most: setting bleed so no white edges show, downloading the correct assembly instructions, and building the black-and-white mask files that switch on a Spot UV or WonderFoil finish. If file setup is new to you, our bleed and trim guide and CMYK vs RGB guide cover the fundamentals first.

Want a box shape we do not list, or a fully custom size? Read how to get custom boxes, or browse custom box printing to see the packaging we run in-house.

Bleed is the strip of artwork that runs past the cut line so a tiny shift on the diecutter never leaves a white sliver on the edge. For every packaging product the bleed is 1/8" on each side, which adds up to 1/4" total across the sheet. Extend any background color, pattern, or photo a full 1/8" beyond the trim, and pull live text and logos at least 1/8" inside it.

Always design on the 4OVER4.COM packaging template for your exact box. The template carries the dieline, the fold scores, and the glue tabs, so your panels land in the right place when the flat sheet folds into three dimensions. For a refresher on trim math and safe zones, see our bleed and trim guide and the standard print sizes reference.

WonderFoil turns a wide range of CMYK colors into a radiant, multi-colored foil, so you can put several foil colors in one design and transform solid areas, halftones, gradients, and reversed-out shapes into a sparkling metallic finish. Like Spot UV, it needs a black-and-white mask uploaded with your full-color CMYK file: 100% black where you want foil, and white where you do not.

Keep a few rules in mind for clean WonderFoil business cards from 4OVER4.COM:

• Printed on 16-point gloss cardstock with a hi-gloss UV coating.
• Foil is available on the front, the back, or both sides.
• Make sure the mask and the CMYK print file line up and match exactly.
• Avoid very thin or small text and art. Use sans-serif fonts above 12 point for the sharpest result.
• White in the CMYK file that reads as 100% black in the mask prints as metallic silver foil.
• WonderFoil pops most on lighter colors. The darker the CMYK color underneath, the softer the foil effect.
• Watch for a white halo around any knockout, and use the fix below if your art calls for one.

To avoid the white halo around a knockout, grow or stroke the WonderFoil area in the mask by about 12 pixels so the foil bleeds slightly into the CMYK area. Filling the knockout with a color reduces the effect further. As with Spot UV, save the foil mask in its exact final position, because 4OVER4.COM cannot be responsible for a mask that is placed incorrectly.

For a printed sample of the example above, and of 16-point high-gloss UV WonderFoil business cards, contact us and ask for samples. To compare foil methods, see our foil stamping guide and spot color guide.