Device for manufacturing a reinforcement from a thread laid directly in its final position by spraying lengths of the thread onto a receiving surface. The thread lengths are delivered from a conduit to a guide as the conduit rotates about an axis. The guide includes deflectors forming therebetween a slot having a thread inlet orifice and a thread spray (discharge) orifice spaced apart along the guide's height. The separation between the deflectors narrows toward the spray orifice, wherein the deflectors form therebetween an angle in the range of 3° and 7° when measured at any point along the height of the slot.