Summary I'm developing this system for my Da Vinci 1.0 Open printer. . This new hotend has a 19mm. teflon barrel and a heat sink that I made on zamak spincasting. This is complemented by a brass nozzle. With this new system, the plastic filament is kept cold until it reaches the nozzle tip. It stays super cold. Im very happy. The carriage has a double fan. The front is to cool the heat sink. and the back, is to cool the filament coming out of the nozzle when printing Through a duct located inside the carriage. This version is for 15mm linear bearings. But it will also be available a version for mounting on original bushings. UPDATE 11 may 15 Some improvements in the design of direct drive / file now included. Some improvements in the design of the carriage and mounting system. Update 15/may/15 Carriage replacing the original file. changes in the fastening system and overall desing. Direct drive bracket. file replacement. adjustments to the fastening system and overall desing.