Project Step 1: Mask

Designing your project is a critical step for irid-on-irid fusing. Here are two important guidelines:

  • Leave about 0.5 inch (12 mm) around the edge of both pieces of glass unmasked. This will ensure that both layers fuse together.
  • Design so that you have a good mix of overlapping and non-overlapping irid. The beauty of this technique comes from the different possible irid combinations.

There are different approaches to masking with tape. You may cut designs out of the tape and then apply them to the glass OR you can simply cover areas of glass with wide swaths of tape and, using the craft knife, cut and peel away the area you want to expose.

When using white glue to draw lines, keep in mind that crossed lines will flow together. To maintain crisp intersections of glue lines, draw one line first, allow it to dry, and then draw the crossing line.

Here are the masked pieces of glass for the example shown in this tutorial, using both tape and glue (in this case for dots):

Irid-on-Irid technique

The black circles on the clear glass are marker lines on the back side of the glass. They’ll burn away during the firing.

Notice that the outer margins of both pieces of glass are bare, in accordance with the first design guideline above. This will allow for a glass-to-glass fuse all around the edge of the project.

The glass is ready for the sandblaster!