RECONSIDER USING TUBES FOR BIAS TAPE FOR STAINED GLASS QUILTS.
If you are making the tubes to use between the sections of the stained glass, take a look at Clover Quick Bias Fusible Tape. It is .25 inch wide with each edge folded in and is available in several colors. Black is stunning for the stained glass.
Jo-Ann's coupons makes it reasonably priced.