A spaced rivet is a tube rivet
or wire rivet
with an added step. The rivet (whether it’s wire or a tube) will be encased in a tube. This tube is sandwiched between the layers, and acts as a stop to keep them separated.
The key to successful spaced rivets is that the outer tubes (or “spacers”) should be a tight fit to the center rivet, so that you can set the rivet without it bending and collapsing inside the spacer. Also make sure to cut your spacers to the exact same length in order to ensure that the spacing is the same all the way around the piece.
Insert a rivet through the top layer of the piece, the spacer, and then the bottom layer of the piece. Set the rivet (figure at right). You can use tape to hold the assembly together while you set the rivets one at a time.