Uroboros Fusion FX / 90 COE casting billets are hand poured into handy rectangles to minimize bubble count, and are made from our unique ultra-low-devitrification glass. They are ¾” x 6” x 9” (1.9cm x 14.4cm x 21.6cm) and weigh approximately 3.7 lbs (1.7 kgs) each. They are fully compatible with all other Uroboros Fusion FX90 COE products, and are compatible to Bullseye fusible products.
Our FX 90 COE billets are annealed, and are easy to cut in straight lines with a simple score and a thick glass breaking tool or a sharp tap on the opposite surface. Like cutting sheet glass, this takes a little practice and confidence, but once you get the knack of it you’ll never look back.
Billets can be laid into molds flat, stacked, or shingled. Shingling may provide the lowest bubble count results. To achieve a clean top edge on open face castings, be sure to hold glass back from the mold edges a ½” or so, so that the melting glass touches the bottom edge first, then rises up the mold wall. You want to avoid letting the melting glass touch the top rim of the mold until very late in the firing.
Questions about firing? When planning a firing schedule for heavier castings, please refer to our Firing Guidelines. Bear in mind that firings of 90 COE glasses typically require slightly higher temperatures than higher COE glasses.
If you are working in smaller scale or in closed molds, and find you are usually cutting billets down to fit into your mold, consider using Billet Chunks. These are pieces pre-cut from whole billets, so you benefit from the low bubble count of the billet form, but are likely not to have to cut them to size.