Find the Right Ink Trap for Your Press
Ink trapping is how ink settles into the recessed areas of type. Get the right thickness to prevent bleeding, streaking, or poor ink laydown.
Ink Trap Calibrator
Your Recommended Settings
Common Scenarios
100 GSM Cotton Rag
Oil-based ink, medium pressure. Trap: 0.35mm. Ideal for letterhead and business cards.
80 GSM Newsprint
Water-based ink, light pressure. Trap: 0.25mm. Watch for ink soak-through.
120 GSM Linen
Oil-based ink, heavy pressure. Trap: 0.45mm. Excellent for book covers.
Troubleshoot Your Prints
Ink Bleeding
Reduce pressure or use a drier ink. Trap depth may be too shallow.
Streaking
Increase ink load slightly. Check roller height and ink distribution.
Weak Trap
Increase pressure or use oil-based ink. Trap depth may be too aggressive.
Quick Reference Guide
| Paper GSM | Oil-Based Trap | Water-Based Trap | Typical Drying |
|---|---|---|---|
| 60-80 | 0.30mm | 0.20mm | 10-15 min |
| 90-110 | 0.35mm | 0.25mm | 15-20 min |
| 120-150 | 0.40mm | 0.30mm | 20-30 min |
| 160+ | 0.45mm | 0.35mm | 30+ min |
Understanding Ink Traps
In letterpress printing, the ink trap is the area where ink accumulates in the recessed parts of type. Getting this right means the difference between crisp, readable text and muddy, illegible prints.
The depth of the trap depends on three main factors: paper absorbency, ink viscosity, and printing pressure. Thicker paper requires deeper traps because the impression creates more recess. Oil-based inks are less absorbent than water-based, so they need slightly more pressure to achieve proper trapping.
Start with these guidelines and adjust based on your press. Always test on a small section first. Environmental factors like humidity can affect drying time and ink behavior. Keep a log of your successful settings for future reference.
Common mistakes: Using too much pressure causes ink to flood and bleed. Too little pressure results in weak traps. Ignoring paper grain direction can lead to inconsistent impressions. Always check that your type is clean and free of old ink residue before making adjustments.
This calibrator was created to help both beginners learning letterpress and experienced printers working with new paper or ink combinations. Your saved profiles are stored locally in your browser and can be exported as notes for your workshop records.
Last updated: January 2026