In 1929, after more than ten years devoted to painting, obtained a fellowship that allowed him to travel to Paris. He carried with him a set of Cézannian works of his, figures and landscapes of a luminous coloring and a rich substance, which he exhibited at the Zak Gallery.
In his indefatigable yarning about learning and experimenting, Del Prete quickly assimilated the lessons of Cubism and Fauvism as well as the example provided by artists such as Arp and Torres García, with whom he kept a personal relationship.
Under these influences, he performed his own abstract rehearsals.
Encouraged by Massimo Campigli, he presented works at the Salon Surindépendant, to which he returned in 1932 with non-figurative collages. This feature also prevailed in the works belonging to his second individual exhibition, performed at the Vavin Gallery.
Del Prete joined the Abstraction-Création association, formed by a dissimilar group of abstract artists, among which were Barbara Hepworth, Delaunay, Nicholson, Gleizes, Herbin, Pranpolini, Schwitters, Max Bill, Calder, Gabo, Hélion, Kupka, Mondrian, Moholy-Nagy, Pevsner, Van Doesburg, Vantongerloo, Sophie Tauber-Arp and Vordemberge-Gildewart, with whom he exhibited his works. Two of his collages, worked out through irregular shapes, usually organic and organized according to a free composition, were reproduced in No. 2 of the Abstraction Création art non figuratif magazine in 1933.
By that time, he went back to Buenos Aires. There, at Amigos del Arte, he presented an exhibition entirely formed by abstract works from his European production, which was the first of this genre ever performed in Argentina. In 1934 and in that very same place, Del Prete exhibited for the first time in his nation a group only composed of abstract sculptures. Yente points out that these samples met then a cold indifference, if not mockery and incomprehension.

The collages, in which the artist allowed cohabitation of oil with humble elements such as matches, packthread, wire netting, packaging papers or cardboard; his paintings, worked out through thick impastos and daring color combinations; his filiform sculptures in metal rods or his plaster carvings, did not only contain material that defied artistic orthodoxy, but also that kept a distance from nature –though they captured its rhythms–, a detail hardly perceived by the audience at that time.
Eager to maintain his independency Del Prete would never tie himself up to a particular trend. He went over the rigors of geometry throughout the 30s and 40s, while he reincorporated figuration, deceived, at a beginning, about the slight comprehension he observed towards his abstract work

and then as a creative option.