cgbenner

@Oliveros Thank you for responding. I appreciate your input. I can assure you that the model is correct, Inventor and Fusion both model threads based on ASME and ANSI thread standards. The geometry was based entirely on NOMINAL threads specs taken from those standards and the Machinery Handbook. I've been doing mechanical design and drafting for over 25 years, and I am an Autodesk Expert Elite member. Not to brag, just trying to assure the readers of this thread that I have modeled threads before. This ain't my first rodeo. If you re-read my original post, you'll see that one of these threads was actually usable, though still leaning in one direction. Here is a screen shot of my modeled threads, compare this to the image in my original post. The orange part at the bottom of the image, was printed from THIS model.

Hi, We have been trying to get a decent print of UNC threads off of our Printer. Ultimaker 5 using Cura slicer. Variety of materials. We have gotten one good part that can print repeatedly in ABS, Polypro and even Kynar. But every part since, modeled in either Inventor or Fusion, has had the threads coming out on an angle leaning upward in the direction of the print (bottom up). The threads are also kind of squished, and have a seam running down one side. Needless to say we cannot get a nut on any of these. What questions should I be asking, or information should I be giving.... and what, if any, suggestions do you all have? I have tried with nominal thread data for 1/2-13 UNC Class 1A... with and without an offset "fudge factor". The attached image (look at the shadows) is of a standard 1/2-13 hex bolt, the middle orange piece is the one that works though you can see the angle there as well, the third piece is from this morning and the leaning angle of the threads is pretty visible in the shadows.