After watching a glass blowing demonstration in Louisville, Kentucky and another earlier this year in Canal Fulton Glassworks, Ohio we took the opportunity to watch some other techniques at the Sunspots Studio in Staunton, Virginia.
Sunspots Studio provides the facilities that most local artists could not afford on their own as well as a place to display and sell their work. Confirming what I had read before, becoming proficient with glass takes about a decade and making a whole lot of paper weights and scrap along the way. That is proficient in one technique of which their are many and developing an individual style.
Before the blow pipes are used they must be heated to about the same temperature as the glass which varies with the formulation. The studio claims to be using low temperature glass as an environmental thing but I also suspect it is easier to form. I know high temperature Pyrex is difficult to work.
Colors can be added on the steel table and a careful combination of blowing, heating, and shaping moves the glass to the desired shape with a uniform wall thickness.
The picture of the furnace is not very interesting until you note his left hand is spinning the vase preform while his right hand is spinning another glass color to be added around the outside and then worked into the glass as a color swirl. As you can see red hot glass is red hot and the final colors do not show as the vase is being formed.
Gravity or even twirling elongates the glass which can then be attached to a base before being transferred to another pipe to shape the opening and Voila! a finished vase which only needs to be detached from the pipe, have the base smoothed, and spend many hours in the annealing kiln slowly cooling to a usable room temperature.