In my previous blog I wrote about a technique for improving prints called making a sacrificial tower that will improve the overall quality of your prints.
Okay, really bad image quality. Let me describe it to you. The print on the left suffers from multiple holes in the top because it was such a small part. The hot end remained over the part keeping it too hot and melting holes in the print. The right one was saved this fate by having a small cube, scaled to the same height, printed with it.
Another area where the print can get too hot is where the layer starts and end. This can produce a “zipper” on your print. If your prints are suffering from obvious zippers or hot spots in the top the best way I’ve found to fix it is to force the hot end away from the print for a moment. The best way to do that is to either print 2 identical copies of the object or make another object that can be thrown away afterwards, preferably small enough that it won’t waste too much plastic.
It is easy to create a sacrificial tower in Makerware/Desktop. Simply add a 20mm calibration cube, move it away from the print (remember the objective is to get the hot end away from the print for a little bit every layer), then switch to scaling, uncheck “Uniform scaling” and set X to 4mm, Y to 4mm, and Z to the same height as the object in the print. Then slice and print and watch your print quality improve.
