A solder paste or other viscous material screen printing machine in combination with paste or viscous material applicator (1) device and an adaptor device (41) in between the reciprocating mechanism for transmitting the pressing forces of the reciprocating mechanism to the applicator device (1) whilst limiting the downward movements of the reciprocating mechanism to be within acceptable limits, with said adaptor device comprising a pressure receiving member (47) and to be acted upon by one or more pressing members (44) of the reciprocating mechanism of the screen printing machine in a downward direction, and piston displacing means beneath said pressure receiving member (47) which means, in use, is downwardly displaceable together with the pressure receiving member to cause the piston (7) to be displaced downwardly when said pressure receiving member is acted on by said pressing members and to urge solder paste or other viscous material contained within the reservoir downwardly, and one-way movement enabling means (46) operatively connecting said pressure receiving member (47) to said piston displacing means such said one-way movement enabling means (46) is such as to normally only permit movement of said pressure-receiving member (47) in an upward direction away from said pressure members; and wherein said pressure-receiving member is biased away from said pressing member so as to be displaceable upwardly to its original position following each downward displacement thereof and release.