This article explains how to create and manage paper substrate definitions in GelatoConnect and link them to your machines in Machine Park. By setting up substrates, you provide your Workflow Builder with the information it needs to automatically select the correct paper for each production job — including dimensions, grammage, and printable margins.
💡 This feature is available for all PSPs using GelatoConnect with Machine Park and Workflow Builder enabled.
Overview
Paper substrates represent the physical sheets and rolls of media you hold in your facility. Each substrate record captures the key attributes of a media type — such as dimensions, weight, thickness, and format (sheet or roll). Once created, substrates can be linked to one or more machines in Machine Park, along with machine-specific settings like printable margins and feed direction.
When a job enters your workflow, the Workflow Builder uses these substrate-to-machine links to determine which paper to use and calculates the printable area for accurate imposition.
Where you'll find substrates and how they're named
The top-level category was renamed to Substrates in May 2026 — what was previously called Paper. It sits alongside the Large format category in the Catalog menu.
Roll substrates use Length, not Height. On roll-type substrates, the second dimension is labelled Length with metres as the default unit (you can still switch to imperial).
Paper weight accepts pounds. You can enter weight in grammage (gsm) or pounds (lb cover, lb text, lb bond) — the system stores the value in the unit you entered.
Attribute values are human-readable. Substrate attribute values are shown using display labels like "A4 (210 × 297 mm)" rather than internal codes — both in the UI and in the catalog export.
Stage 1: Creating Paper Substrates
Navigate to the Paper Substrates page from the main menu.
Adding a Sheet Substrate
Click Add Substrate and select Sheet.
Enter a descriptive name for the substrate (e.g., “150 gsm White Silk”). Including the weight, colour, and finish in the name makes it easy to identify later.
(Optional) Add a brand name if this substrate is specific to a particular paper brand. Leave blank if it applies generically.
Fill in the physical attributes and Save
Name — a clear, descriptive name for the substrate. This is what shows up in dropdowns when configuring product models. Example: "200gsm uncoated A4."
Substrate type — the format the substrate comes in: paper sheet, paper roll, large-format roll, and so on. Determines what dimension fields appear below.
Weight — paper weight, in grammage (gsm) or pounds (lb cover, lb text, lb bond). The system stores the value in the unit you entered, so US conventions are preserved.
Thickness — typically in microns or mils, depending on your unit preference.
Dimensions — for sheet substrates, Width × Height. For roll substrates, Width × Length, with metres as the default unit on Length. You can switch to imperial on either dimension.
Brand (optional) — pick from the brands defined in your tenant. Useful when the same substrate type is sourced from multiple paper mills.
Colour / finish (if applicable) — for substrates that come in multiple colours or finishes.
SKU or product ID — internal identifier used to match the substrate against procurement and production data.
Adding a Roll Substrate
The process is similar for rolls. Click Add Substrate and select Roll. In addition to the standard fields, you can specify the roll type in Media Type:
📝 You can create as many substrate records as you need. Each record should represent a distinct combination of media format, weight, finish, and dimensions that you stock.
Stage 2: Linking Substrates to Machines
Once your substrates exist, link them to the machines that use them.
Navigate to Machine Park and open the machine you want to configure.
Go to the Substrates tab.
Click Link Substrate and select the substrate from the dropdown list.
Set the printable margins (top, bottom, left, right) in millimetres. These margins define the non-printable border area and are passed to the Workflow Builder for imposition calculations.
Select the feed direction: choose Short Edge or Long Edge depending on how the paper is fed into the machine.
Click Link Substrate to save.
Repeat this process for every substrate that a machine supports. Over time, you will build a complete matrix of which substrates are available on which machines.
⚙️ The printable margin and feed direction values are sent to the Workflow Builder at job execution time, so accurate values are important for correct imposition.
Tip: Use the search field at the top of the Substrates page to find a substrate by name, SKU, or product UID. Results filter as you type, across all pages of the catalog.
Working with substrates in GCP
Substrates defined in Core Catalog already flow through to GelatoConnect Procurement automatically. From the Substrates page, select one or more substrates and use Add to Supplier to assign them — set price, MOQ, purchase unit, and the inventory toggle in one step. The GCP Status column on the Substrates page shows which substrates are already linked to suppliers and how many.
Substrates created through the AI Estimator flow are also surfaced here without re-entry — once they exist in Core Catalog, the same Add to Supplier flow applies.
Frequently Asked Questions
Can I link one substrate to multiple machines?
Yes. A single substrate can be linked to as many machines as needed, each with its own margin and feed direction settings.
What happens if I edit a substrate after linking it?
Changes to a substrate’s core attributes (dimensions, grammage) are reflected across all linked machines. Machine-specific settings (margins, feed direction) are stored separately on the link and are not affected.
Do I need to create substrates before setting up workflows?
Yes. Your Workflow Builder references the substrate-to-machine links when determining which paper to use, so substrates should be created and linked before building production workflows that depend on them.