Instructables

Step 4: Attach the mask to the blank board

Carefully cut out the mask for the copper side from your printout. Place it face-down onto your board, so that the toner faces the copper. I use tiny bits of scotch tape on each edge to hold the mask in place. That might not be necessary if your blank is somewhat larger than your mask. I found that the mask tends to slide if it's not securely taped; you want to avoid that when working with tight tolerances.
nickjohnson8 years ago
Use SMALL pieces of tape, as they get hard to remove after ironing...