A system for making a fitted cap, the fitted cap configured to apply a shaped sealant shroud to a portion of a fastener, the system comprising: a support plate, comprising: a first side; a second side, opposite the first side; and a first plurality of through-openings, penetrating the support plate from the first side through to the second side; a fastener template, dimensionally identical to the portion of the fastener and extending from the first side of the support plate such that the first plurality of through-openings is arranged about the fastener template; a precursor cap, comprising a first surface, geometrically complementary to the fastener template, and a second surface, opposite the first surface and parallel to the first surface; first means for heating a first polymer sheet to a specified temperature; and second means for applying suction to the first polymer sheet, positioned a predetermined distance from the first side of the support plate and heated to the specified temperature by the first means, through the first plurality of through-openings from the second side of the support plate to vacuum-form the first polymer sheet over the precursor cap, wherein the second means is configured to apply the suction such that: after vacuum-forming the first polymer sheet over the precursor cap, at least a portion of the first polymer sheet forms the fitted cap and a first inner surface of the fitted cap is geometrically complementary to the second surface of the precursor cap. a support plate, comprising: a first side; a second side, opposite the first side; and a first plurality of through-openings, penetrating the support plate from the first side through to the second side; a first side; a second side, opposite the first side; and a first plurality of through-openings, penetrating the support plate from the first side through to the second side; a fastener template, dimensionally identical to the portion of the fastener and extending from the first side of the support plate such that the first plurality of through-openings is arranged about the fastener template; a precursor cap, comprising a first surface, geometrically complementary to the fastener template, and a second surface, opposite the first surface and parallel to the first surface; first means for heating a first polymer sheet to a specified temperature; and second means for applying suction to the first polymer sheet, positioned a predetermined distance from the first side of the support plate and heated to the specified temperature by the first means, through the first plurality of through-openings from the second side of the support plate to vacuum-form the first polymer sheet over the precursor cap, wherein the second means is configured to apply the suction such that: after vacuum-forming the first polymer sheet over the precursor cap, at least a portion of the first polymer sheet forms the fitted cap and a first inner surface of the fitted cap is geometrically complementary to the second surface of the precursor cap. after vacuum-forming the first polymer sheet over the precursor cap, at least a portion of the first polymer sheet forms the fitted cap and a first inner surface of the fitted cap is geometrically complementary to the second surface of the precursor cap.