His current craft focus was not directly determined by artistic or professional education. He gained knowledge of glass processing only at the production cooperative Krištáľ in Valaská Belá, where he worked from 1996 to 2007. Here he acquired comprehensive knowledge of glass and its shaping, which he also utilizes today in operating his own glass-making skanzen in Valaská Belá, where he passes on the craft to future generations.

His glassware assortment is wide-ranging. Without the use of machines, he produces products primarily in small series or as unique pieces using free shaping and molds, utilizing recycled materials. A typical feature of his products are bubbles, resulting from insufficient glass melting, which was typical for folk glass, or uneven thickness of product walls. The products of Peter Dolinaj are also diverse in shape. In the production of series pieces, such as glasses, he also utilizes molds (wooden or metal). He is skilled in working with molds as well as free shaping of products. He also independently makes tools – containers for melting glass. Among his assortment, special mention should be given to chalices or so-called “mucháre” – replicas of traditional glass products. “Mucháre” still serve a function today, they are stable and easy to transport. Also noteworthy are undecorated pub glassware and from it, now rare but characteristic Slovak drinking glasses, which the glassmaker creates mainly from greenish glass by blowing into molds. From utility glass, there are further square bottles with long, narrow necks, stemmed glasses, glasses with or without plastic decoration, shot glasses, steins with attachments, clean or ornamented carafes, etc. Charming items include small oil lamps or elaborate pipes, showcasing the glassmaker’s patience and creativity. The author’s free compositions are also varied, containing small colorful souvenirs, crosses, as well as larger utility or decorative one-of-a-kind pieces.

In 2021, he was awarded the title of Master of Folk Art Production for his activities.