The newest revision of our filament dryer that comes with a large spool expansion kit includes the capacity to dry one 2-4kg spools or two 1kg spools at the same time. It includes a filament drying guide with the proper drying temperature and time for a wide range of filaments on a laminated reference card. Best practice is to dry filament per the guide upon opening, then load the filament in the Materials Management System (MMS), or Polybox if a MMS is not available, or now, in some cases, feed directly from the PrintDry (depending on available feed path), to ensure best quality prints in all materials. This process is required for investment casting pattern material and all nylons. It is also highly recommended for all high performance polymers, you will get better looking, more accurate parts and more reliable printing.
Note: It has been our experience that most filaments, as supplied from the manufacture, are not optimally dried, even those that come in vacuum sealed bags. The time and processes between extrusion and packaging seems to almost always allow materials to become wet before packaging. The dry-and-store process eliminates the risk of printing with subpar materials.