What is glassblowing?
A: Glassblowing is a glass forming technique that involves inflating molten
glass into a bubble (or parison) with the aid of a blowpipe (or blow tube).
A person who blows glass is called a what?
A: A glassblower, glassmith, or gaffer.
A lampworker (often also called a glassblower or
glassworker) manipulates glass with the use of what?
A: A torch on a smaller scale, such as in producing precision laboratory
glassware.
As a novel glass forming technique created in the
middle of the 1st century BC, glassblowing exploited what working property
of glass that was previously unknown to glassworkers?
A: Inflation, which is the expansion of a molten blob of glass by
introducing a small amount of air into it.
That is based on what?
A: The liquid structure of glass where the atoms are held together by strong
chemical bonds in a disordered and random network.
Therefore molten glass is viscous enough to be blown
and gradually what?
A: Hardens as it loses heat.
Increasing the stiffness of the molten glass makes the
process of blowing what?
A: Easier.
During blowing, thinner layers of glass cool faster
than thicker ones and become more viscous than what?
A: The thicker layers.
That allows production of blown glass with what?
A: Uniform thickness instead of causing blow-through of the thinned layers.
What are the two major methods of glassblowing?
A: Free-blowing and mold-blowing.
The process of free-blowing involves the blowing of
what?
A: Short puffs of air into a molten portion of glass called a "gather" which
has been spooled at one end of the blowpipe.
This has the effect of forming what?
A: An elastic skin on the interior of the glass blob that matches the
exterior skin caused by the removal of heat from the furnace.
The glassworker can then quickly inflate the molten
glass to a coherent blob and do what?
A: Work it into a desired shape.
Researchers at the Toledo Museum of Art attempted to
reconstruct the ancient free-blowing technique by using what?
A: Clay blowpipes.
The result proved that short clay blowpipes of about
30–60 cm (12–24 in) facilitate free-blowing because they are what?
A: Simple to handle and to manipulate and can be re-used several times.
Skilled workers are capable of shaping almost any
vessel forms by doing what?
A: By rotating the pipe, swinging it and controlling the temperature of the
piece while they blow.
Mold-blowing was an alternative glassblowing method
that came after the
invention of what?
A: Free-blowing, during the first part of the second quarter of the 1st
century AD.
A glob of molten glass is placed on the end of the
blowpipe and is then inflated into what?
A: A wooden or metal carved mold.
The shape and the texture of the bubble of glass is
determined by what?
A: The design on the interior of the mold rather than the skill of the
glassworker.
What are the two types of molds?
A: Single-piece molds and multi-piece molds.
A single-piece mold allows the finished glass object to
be removed how?
A: In one movement by pulling it upwards from the single-piece mold and is
largely employed to produce tableware and utilitarian vessels for storage
and transportation.
A multi-piece mold is made in multi-paneled mold
segments that join together, thus permitting the development of what?
A: More sophisticated surface modeling, texture and design.
The development of the mold-blowing technique has
enabled what?
A: The speedy production of glass objects in large quantity.