0 Replies Latest reply on Mar 13, 2018 5:30 AM by Gordon Rigg

    Threads for 3D printing - share the pain here

    Gordon Rigg

      I'm still on SW2016 here so I'm hoping that things might have improved in the later versions.

      But in SW2016 it looks like they were in a rush, didnt care much and/or got the apprentice to implement this "real thread".

      thread disclaimer.png

      So rather than SW obtaining thread profiles once for us all, now every single one of us has to look up the standards information ourselves?. Because they have only made some sort of approximation? Come on... how about at least trying to make the information correct but still adding a disclaimer. How about trying to earn a little bit of respect from us engineers here we are not lawyers
      what we appear to have is the correct basic thread form without the fillet radii. I get that the helical radii might tax the system. But how about saying that.

      Without the radii, female threads will accept commercial male bolts. This might not be true for male threads into holes that are cut using taps without some extra clearance.

       

       

      thread sizing.png

      Is it too much effort to make the threads appear in ascending order? That's a pretty basic idea,... next, how about using the selected cylinder/hole size to find the nearest related thread diameter? or did nobody think of that? I thought people tried these functions out before release?

      thread cut.png

      So I chose metric die, and I started my thread at the end of the bolt, and ran it up to the underside of the head - like it was a die.

      But the thread starts one pitch in from the starting position, and dug itself one pitch into the finish position inside the bolt head. That isn't what a die does is it? Someone doesn't understand what a thread start means, or which way dies work.

      thread start.png

      So I pretend the thread starts under the head and finishes where it starts. Thats better.

      thread finish.png

      But the thread stops in an unrealistic way. But surely SW included some thread run out options...

       

      No they didn't...

      thread runout.png

      Here I have revolve extruded to make a conic that runs the thread over a distance of one pitch to finish half a pitch from the finishing (or starting) face, to make it look realistic, and print without a weak point. all based on geometry that is already there. So adding a thread run out over x pitches, finishing y from face would be a very simple additional function.

       

      This is SW 2016 SP5

      Please now everyone tell me how much better it is in 2017 and 2018?

       

      Sorry for the rant. I feel better now