Continuation of the article „From the idea to the finished product part 3 ….
In part 3 of our article „From the idea to the finished product“ we discuss the further processing of pressed glass articles.
Removal of excess glass
Once the article has been completely cooled, the excess glass on the edges of the article must be trimmed from the edge of the product itself. This can be done in several different ways. The process depends chiefly on the size of the article. Either a special blade is used to make the dividing line and to chip off the excess glass or a so-called shearing wheel is used to cut off the excess glass. Some articles are also „drilled out“, i.e. a suitable hollow drill, which is bigger than the diameter of the glass product, is used to „drill out“ the edge. This process is only suitable for round articles up to a certain size. More information about the manufacturing-processes can be found here.
Working on the „seam“
Now the glass article has a sharp and porous seam where the upper and lower parts of the mould join. This must now be polished away or neutralised as much as possible, using grinding and polishing techniques, among other things, in accordance with the customer’s requirements. Depending on the product and the customer’s requirements, this post-treatment process is very time-consuming and requires the necessary expertise and a high level of skill.
Quality control at Schäfer Glas
As soon as these process have been completed, the process of quality control begins. The glass article is subjected to a thorough check. Are the customer’s requirements in terms of sizes, dimensional tolerance, surface quality etc. complied with? Is the glass clean, schlieren and blister-free? Does the colour comply with the customer’s requirements? Does the article fit into the „slot“ we have supplied (e.g. for pressed glass articles which are built into bathroom fittings)? As soon as these criteria are checked and the article has passed all the necessary tests, order picking and packaging for delivery can begin. It is also possible to process the glass yet again. Check back soon for more on this topic in part 4 of our article „From the idea to the finished product“. In today’s blog we described the processing of pressed glass articles in some more detail – outlining the individual steps which are necessary once the article has left the glass press. This is how an unfinished part becomes, for example, a glass cone or a glass lens.