Starting from 1950 onwards, he gradually developed a constructivist style, favoring geometric shapes, cutting and folding sheets of iron, steel wires and aluminum. He joined
Grupo Frente, in 1955. The next year, he returned to
Rio de Janeiro and participated in the
National Exposition of Concrete Art in 1957. In 1959 Weissmann traveled to Europe and East Asia, returning to Brazil in 1965. In the 1960s, Weissmann exhibits the series of sculptures
Amassados (
Dented), which he created in Europe with hammered zinc and aluminum sheets, aligning himself briefly to informalism. Later on he returned to the constructivist works. In 1970 he won the award for best sculptor by the
Brazilian Association of Art Critics and participated in the International Outdoor Sculpture Biennial, in
Antwerp,
Belgium, and at the
Venice Biennale. Weissmann made several public art sculptures for Brazilian cities, like at
Praça da Sé, in São Paulo and at Parque da Catacumba, in Rio de Janeiro. He kept studios in
Belo Horizonte (1950);
Madrid, (1962) and
Ipanema, Rio de Janeiro (1956 and 1965). == Individual exhibitions ==