You can usually tell by looking at it if you see any bubbles. If the bubbles are there or moves around then you have more freezing to do. Once the ice...
This is my instructable. WARNING! THIS IS A FIRE AND HEALTH HAZARD. I TAKE NO RESPONSIBILITY FOR WHAT EVER YOU DO WITH THIS PROJECT.
Step 1: Tools and Materials
My project is making a Halloween Shot Glass. These are the pictures I have. You take a soldering iron a bucket filled it with ice and water. I think all the ice melted but that doesn't mater. The bucket of water and ice or just water is to cool down the iron to make it safer to use. It may not protect you if you do something stupid with it.