Supply notes Minimal
Vellum Weight and Printer Compatibility
Feeding four vellum weights through a laser printer and an inkjet and measuring curl, toner flake and whether the sheet survived at all. Two of the four should never go near a printer.
5 layers 6 min
Why vellum jams
Vellum is translucent because it is heavily calendered and mildly plasticised, which makes it smooth on both sides. A printer's pickup roller relies on a friction difference between the two faces; when both faces are equally slick the roller cannot separate the top sheet from the stack, and you get a double feed. The fix is a manual feed, one sheet at a time, every time.
Laser: toner sits on top
Laser toner is a plastic powder fused at about 180 degrees C. On vellum it does not sink in — it sits on the surface as a slightly raised, slightly glossy layer. On the 90 gsm sheet this produced 9 mm of curl as the toner cooled faster than the paper and shrank. On 112 gsm and above, curl stayed under 3 mm. If you rub the printed area with a bone folder edge on 90 gsm, the toner flakes off in sheets.
Inkjet: the coating question
Vellum has no inkjet receptive coating, so water-based ink sits on the surface and dries by evaporation — 4 to 11 minutes depending on weight, during which the sheet absorbs water and waves. The 205 gsm sheet absorbed almost nothing and the ink beaded. The 112 gsm sheet was the only one that gave an acceptable result: legible text after 6 minutes, wave under 1.5 mm. Never use the duplex setting.
The alternative that always works
Print onto 100 gsm tracing paper instead and mount the tracing paper under the vellum. Tracing paper is designed for toner and takes it without curl. You then have the vellum's surface and translucency on top and a compatible printed layer underneath, at the cost of one extra 0.09 mm of bulk.
Assembly order
- 1Fully separate the sheets before loading — vellum sticks to itself at the edge.
- 2Load one sheet at a time in the manual feed, textured side up if there is one.
- 3Print and immediately remove the sheet; do not let it sit in the output tray.
- 4Lay flat under a 2 kg weight for 20 minutes before measuring curl.
- 5Test the toner bond with a bone folder edge before committing to a run.
About 6 minutes of bench time, plus whatever the adhesive needs.
Supplies
- Vellum sheets 90 / 112 / 150 / 205 gsm
- Laser printer manual feed tray
- Inkjet printer rear straight feed
- Digital caliper 0.01 mm
- Bone folder for the flake test
Curl and adhesion after printing, 20 minutes
| Vellum | Laser curl | Toner flake | Inkjet result |
|---|---|---|---|
| 90 gsm | 9 mm | heavy flaking | beads, unusable |
| 112 gsm | 2.8 mm | light rub-off | acceptable, 6 min dry |
| 150 gsm | 2.1 mm | none | wavy, 9 min dry |
| 205 gsm | 1.4 mm | none | beads, unusable |
Where this goes wrong
Vellum sheets are often packed with a thin interleaving tissue that looks like part of the sheet. Feeding that through a laser printer melts the tissue onto the fuser roller and ruins the printer.
