Stainless Steel Ribbon Expansion Joints

Stainless steel ribbon molds are easy to make using our two different sizes of Stainless Ribbon. The trick is to make sure you have expansion joints so your glass doesn’t crack as it fires. We’ll focus on two different types of joints today, a sleeve joint and a tab joint.

Materials for Ribbon Molds
Materials for Stainless Ribbon Molds

Materials:

3/4″ Stainless Steel Ribbon

Square

Fine Point Sharpie

Airline Snips

Flat nose pliers

Tab Joint

Tab joints are used on the outside of ribbon molds to give glass room to expand. We are using a 1/2″ ribbon for this example:

Using the square, make sure the end of your ribbon is square, then mark intervals at 1/2″ and 1″
Squaring up the ribbon
Fold the 1″ mark into a right angle, this is the part of the joint that holds the tab
Fold the 1/2″ mark all the way back down
Your folded part should look like this
on the other end of the ribbon mold, mark a tab that is slightly less than 1/2″
Fold this tab up to a right angle. The tab needs to slip into the joint, so make sure you fold in the right direction
Finished tab expansion joint
Circle mold ready to line and fill with glass

Sleeve Joint:

Sleeve joints are exactly what they sound like, a sleeve of stainless ribbon that holds the ends together, but allows them to also slide apart slightly as your glass expands and contracts. These expansion joints can be used on any ribbon mold, but are especially good for making hollow shapes inside larger pieces of glass. Let’s get started:

Mark a section of ribbon to use as a sleeve that is at least twice as wide as the ribbon. We are using 3/4″ ribbon, and using a 1.5″ sleeve
Center the ribbon over the sleeve and mark both sides
Fold the edges of the ribbon into a sleeve
Folded Sleeve
slip ends of ribbon into sleeve and crimp tight
Outside of sleeve ribbon
Finished ring mold inside larger ring
both molds lined with shelf paper, ready to fill with glass

Examples of mold shapes

Examples of Glass made in a ribbon mold

Tips and Tricks for Success

  • Always line ribbon molds with shelf paper
  • Ribbon molds can be used for tack or full fuse, and have been tested up to 1900 degrees for stability
  • For large or complex molds, it is wise to brace around the edges with kiln furniture to keep the mold and glass in place during fusing
  • for pot melts, the ribbon mold will need to be weighted down to prevent glass from flowing under it
  • make sure folds are perfectly square to ensure mold sits perfectly flat
  • ribbon molds can be reshaped after firing, although extensive bending will eventually produce metal fatigue and can cause breakage
  • CAUTION! Edges can be sharp

Tack Fuse Firing Schedule for Float Glass