This short blog is for any nerds that my be following my 3D printing adventures. If you are not into 3D printing, none of the following will make any sense. Suffice it to say that my large custom built 3D printer has just undergone a major upgrade to improve both reliability and accuracy. With more test time it may also yield more speed. The field of 3D printing is ever improving and it is beneficial to stay abreast of these improvements and incorporate them into your equipment.
After several years of using the more-or-less stock hot end of my Ender 6 based printer I decided that migrating from a Bowden tube to a direct drive filament feed system was worth investigating. The stock Bowden tube setup required too much retraction (6.5 mm) and was prone to clogging. When you are printing very large objects that take four days and the better part of a spool of filament to print, a clog is not just annoying , but also expensive and time consuming. I had resisted changing to a direct drive system because of the mass of the extruder being located on the moving print beam. Theoretically, this will limit the maximum print speed that can be obtained. In the end, I have decided that reliability is more important than speed. I currently print at reduced speeds, acceleration and jerk to improve print quality, so the mass of the extruder will not be a major factor until I push the printer much harder than I currently do.
I have installed a Micro Swiss NG system on the printer. It incorporates a very compact direct drive filament feed system with an all metal hot end that looks to be much less prone to clogging. The retraction is now reduced to 1 mm and I have seen no stringing whatsoever. The first print (a hybrid housing) had excellent detail and is almost perfectly flat from the head to the foot. I attribute this to the improved cooling. As long as I was upgrading everything else, I increased the part cooling fan and that seems to be improving print quality.
With one hybrid housing printed I am feeling very positive about the upgrade. It has the potential to increase throughput and keep continued production of the hybrid line of dulcimers feasible. This is a very good thing because the project has already raised thousands of dollars for some very worthy charities.