The Replicator 2x was made for printing ABS but I enjoy the ease of printing with PLA. I was more interested in the heated build platform for a wider range of material capability as well as the dual extruder for printing with PVA support material. In general though, I prefer using PLA and without an active cooling fan the prints aren't excellent. This mount will allow the attachment of the same fan used in the Rep 2 for active cooling for each individual extruder. This is still a work in progress and still isnt meant to work yet so dont try it unless you plan on modifying to offer suggestions and improvements. I will not take responsibility for a damaged machine. This is the google groups page for the topic, which includes links for the fan needed and the connector used to connect it to the motherboard on the first post. https://groups.google.com/forum/#!topic/makerbot/d6R9Rm_QTqc I will post instructions once the final piece is done and tested Versions: 1.01 First upload 1.02 Added easily removable support structure for top platforms and narrowed the vent ends to point more directly at nozzle