Thread identification and options

derek_ward076

I found a model online that, when 3D printed, had threads which were fantastic. Comparing it with what threading options that we currently have I can't make out what type they are. Does anyone have any guesses as to what type of threads they are and how I might model them (hopefully via a FeatureScript)? Thank you!


versus what I can get via the ThreadCreator FeatureScript:

S1mon

Those look like plastic bottle threads. There are a number of standards for these. As far as I know, they are all moldable with two slides and the thread is cut in an injection molding tool with a mill bit which is somewhat like a t-slot cutter - not a tap.

It would make a lot of sense for there to be a custom featurescript for plastic bottle closures, but I haven't seen one yet.

Here are documents about some of the different thread types:
https://www.sanleplastics.com/solution/plastic-bottle-cap-threads-specifications/

Here's an example of modeling the threads in Fusion 360 (not sure how relevant it is since I think you could probably do this mostly with a sweep in Onshape) which shows some of the details:
https://www.autodesk.com/community/gallery/project/25301/bottle-neck--sp400-modified-buttress-thread-m-style

(Note how the ends of the thread start and stop with a partial revolve of the thread - this is the cutter shape)

derek_ward076

@S1mon
Thank you for your reply! That makes sense that it would be a plastic bottle thread! The printed parts certainly screw together like a plastic bottle! I've never come across any printed threads like it. I'm going to do some testing a bout. Cheers to you!