Next you will cap your glass; this is done by blowing into the pipe then covering the hole with your thumb. The positive pressure from your air being blown into the steel tube/blowpipe makes the air trapped expand inside the pipe, which then creates the bubble this is called your first gather and bubble is called the parison. Once you have an even walled bubble you can again move your steel tube/blowpipe back over to the marver to shape more and then gather more glass.
Tools and how to blow glass continued
Always remember to rotate the rod, cannot be expressed enough. With every move you do if it is on the marver, in the furnace or in the glory hole always continuously rotate. How many times you gather glass will depend on how big your glass piece needs or you want it to be. If you want to add color to your piece this is the time to do it. You will take your piece and roll it onto various forms of colored glass such as powders, fritz and bars. This will add your color and design that you want on your glass piece then place it back into the glory hole so it will melt and form into the clear glass. Once you have accomplished this you should roll your glass piece into a more narrow shape and then reheat it in the glory hole and again continuously rotate your steel tube/blowpipe. With all that done and it is the right size and color if you choose to have color you can now start shaping your piece more to look like more like your finishing product. You will do this by rolling your glass piece onto your marver and it will help to have another person to help blow and create the bubble as rotate your piece in the areas on your piece that you want to go either up or down.
If you want your bubble to move down then you simply marver the sides and not the bottom, that way the sides expands downward. If you want your bubble to expand more on the side, then you simply marver the bottom of your glass piece and not the sides that the sides will expand but not get any longer. Once you are have completed your desired shape you will now cut in a jack line which is known as your tongs. While rotating your pipe with your jack cut and create the neck and other shapes you choose to place on your glass piece by using tweezers to pull the hot glass to form your art, for example if you are wanting to create handles and have your art piece be a fancy pitcher or make it look like a cute animal. When you have finished and completed what you want your art piece to look like now let’s open the glass if you are creating a cup or pitcher and let’s finish your piece.
By doing this you will transfer your glass piece to another rod called that is called a punty. This part can get a little bit tricky so having someone there who knows how to blow glass as well will help you to get through this tricky spot with no mistakes. You need to find a small tool a file works best and dip it in water. Then carefully etch a line around the neck, this weakens the glass and makes it more brittle which makes it easier to separate and move. Once you have created your glass piece or work of art you may now cool it. You will cool your piece down by placing your thumb over the hole of pipe and carefully dip into a bucket of water. By keeping your thumb over the hole it will keep the water inside and not come running out and ruining your glass work. Then a few more reheats in the glory hole so you can trim up any unnecessary pieces sticking out from the sides. Once cleaned up and looking complete and you happy with it you will need to crack your piece off the steel tube/blowpipe with a wooden block. Tap the pipe forcefully so your piece will drop off at the end of the pipe nice and clean. Then you place your new finished piece in what is called an Anneal this will cool off your glass piece. The Anneal is an oven that cools glass at a controlled rate it takes all twenty-four hours for it to be complete.