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Pipe ( NPT ) Threads again
william_lucke
Member Posts: 7 ✭✭
You have customers requesting pipe or NPT threads be added to the thread tool... repeatedly.
OnShape can not be a credible product development tool without pipe threads.
https://forum.onshape.com/discussion/9594/npt-thread/p1
OnShape can not be a credible product development tool without pipe threads.
https://forum.onshape.com/discussion/9594/npt-thread/p1
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Comments
Improvements to Onshape - June 27th, 2022 — Onshape
The hole feature interface has changed since then, but ANSI based tapered pipe tap holes are found on the inch tab and ISO-7 based tapered pipe tap holes are found under the metric tab. ISO-7 and older BSPT have now harmonized, so no need for separate standard approaches at this point.
We do not yet offer tapered pipe threads on the external thread tool in part studios.
We also do not yet offer options for parallel pipe threads for holes or external threads.
Yes, I noticed. Hence this topic.
Thanks a million for sharing those files!! Not only did they provide valuable tools, but I learned quite a bit in the process of digesting what you created in order to adjust for 3d printing tolerances (I'm still a complete rookie with onshape and have pretty limited engineering/drafting knowledge and experience.) If you're ever in the SF Bay area, I'd love to buy you a beer!
Thanks for this. Fantastic. Just used it to make some threaded street elbows:
https://cad.onshape.com/documents/4dd5dad4bc230bf5852a96f8/w/82abaf06ab6c239dd163b10c/e/df48581f161f966e3b2179b9?renderMode=0&uiState=673816422c7145555a6eb3dc
FYI Mate connectors at the full engagement point.
@riley_smith120 - @Oliver_Couch
Glad to hear you guys liked those models. The work flow was to make the tools once, then use that tool over and over. The real advantage is the time saving factor, and maybe even a little less meta-data, compared to modeling threads in every part. Once again I will caution about 3D threads in drawings - just a few can create a mess. My intention was to help a friend create images for a build manual - and I was after realism. Anyone with F.S. skills could probably automate this process if they wanted.
Cheers - Rick
@rick_randall Where does your #DIM_AM come from?:
I thought perhaps it was L4 from the standard, but couldn't match it up to anything.
@Oliver_Couch - You are correct about Dim "AM" (absolute minimum) being Dim "L4". My source was an older (1920's) American Machinists Handbook, but I could have typo-ed that one. And thank you for bringing that to my attention, I will correct that oversight. After looking at the table above, most Dims are very close, but do not match exactly, and I'm going to let them fall into the "tolerance" category. Please let me know If there are any other issues that need looking at. Happy to make any corrections - or feel free to use my workflow to create your own "thread cores" using any standard that you need (this would give you absolute control over accuracy).
Edit, Have made some corrections - you might want to update to latest versions.
2nd edit - Some further explanation - these 3D threads are only supposed to be "representations" to check for basic form and fit, and would normally only be noted with a "call out" on a drawing. A pipe or fitting, generally, is a buy-out item, and the need to detail the thread on a drawing is unnecessary (only the tool & die maker, that makes the tooling needs to worry about this).
As for 3D printing, care should be taken to insure proper clearances, but I think parts made with these "thread cores" could be used as long as the proper offset is used (once again, I have never tried this - and didn't make any allowances for it).
@rick_randall great configured models! btw, you can also place and boolean multiple of these at once using the Super Derive custom feature. It is also possible to create a custom feature that uses these as a basis and derives them, places them, and does the boolean subtract. That feature could have inputs that match all of the configuration inputs.
@rick_randall curiosity got the better of me and I was able to mock up a feature that instantiates your model. Check it out! I linked it to a copy of your part studio since I needed to tweak a few things, but think in the long run it'd be better for it to be linked to yours since you're more likely to maintain the configured models better. Let me know if you're interested and I can help make that happen.
https://cad.onshape.com/documents/b675b9d7712fc8ca1eefa8f6/w/e3f898db2bee36c1a5eaa5e5/e/a973753cca705cc97d36b4d8
@EvanReese - I really like that F.S., I would be happy to work with you on this - but I do have a couple of reservations.
a) Drawings just don't like 3D threads … period - (maybe a cosmetic version could work better?). Been waiting for OS to add pipe threads to the external thread command, so thread call outs would work properly in drawings.
b) those models were a work in progress, and have a lot of extra versions, that they don't need. If 3D threads were going to be used for F.S., I'd probably want to start from scratch, with a new clean model. Is there enough interest in 3D threads?
As an example of the a fore mentioned cosmetic thread see link below (not pipe thread,just a bolt - but shows the idea)
https://cad.onshape.com/documents/7c7fba9256f88a83edeb0770/w/74fc04da4ad96bff3efef263/e/3be849ba0dfcb61f38f1bbba
Send me a DM and let's talk
Edit - just tried to add decal to a conical surface - no luck
just DMed you. Oddly, you can make it conical after the fact and it seems to work
Cool - I got to play around with this for sure
@rick_randall @EvanReese
I have just remade the NPT Tap from ASME B1.20.1-2013 (Current version). Enough for tonight, took a few hours nutting out all the details. I'll have a go at the Die another day, unless someone else is keen first.
https://cad.onshape.com/documents/6333f38436f294951af0cbd3/v/5ab4d6c729c76bff8d7fc946/e/6192f8bcb106c0c92f420ab0?configuration=Custom_Drill_Size%3D0.025400000000000002%2Bmeter%3BDrill%3Dtrue%3BDrill_Depth%3D0.025400000000000002%2Bmeter%3BDrill_Point_Angle%3D2.059488517353309%2Bradian%3BLead_in_Chamfer%3D0.5235987755982988%2Bradian%3BList_e4drDdCvFBsU55%3DDefault%3BList_zdDJcPXnE3VFYu%3DDefault%3BModelled_Threads%3Dtrue&renderMode=0&uiState=673ca870b5fb846867409d6b
I added some extra configuration options, and some recommended and automatic tap drill sizes. I also modelled it so it should default to the correct orientation when you insert it.
Modelled with a middle amount of thread truncation (though if you're that worried, you probably shouldn't be copying this).
I also discovered a discrepency in the standard!:
Wrench makeup distance and L3 should be the same. Therefore it should be the case that L2 = L1 + L3, or equivalently L1 = L2 - L3.
However (using 1-11.5 for example) L1 = 0.4000 while L2-L3=0.4219(13043…)
I went with L1 from the table since there's actually a few discrepancies with the diagrams and the data in the standard. Also there's 3.47 vanish threads for every size (couldn't figure out where the 3.47 comes from for the life of me!), but in the figure there's only 2.5.
I wouldn't have ever thought there'd be any weirdness in a standard this fundamental!
Edit: Whoops. I just realised I made a great pipe thread and not a great tap. Oh well, I'll fix it later.
@Oliver_Couch - Don't alter your model - or at least make a copy, because you can use it to boolean (cut) the male thread die(s). You have already done the hard part. Got to say, I like your work so far.
You should contact @EvanReese and collaborate on the F.S., You seem to have a firm grasp of the concept - no sense having to many cooks in the kitchen.
P.S. As a side note, I found that using a color coding scheme for the "thread cores",(NPT, UNC, UNF…) really helps to quickly find the right choice in my template folder (the thumbnails all look alike, otherwise).
Look forward to seeing what you guys come up with (keep me posted)
@Oliver_Couch Want to collaborate on a simple Featurescript wrapper for your configured models?
Sure.
I've done some updates. Still work in progress. I haven't setup configuration on the internal thread part studio yet, but I copied it over from the external thread so there's enough in there it kind of works. After more learning about NPT (what a rabbit hole!) there are some minor updates I want to make to the external thread model too.
https://cad.onshape.com/documents/6333f38436f294951af0cbd3/w/9f371ad82f705b3646b1c827/e/6815d7bf98e9f6ced9ec206f?configuration=Custom_Drill_Size%3D0.025400000000000002%2Bmeter%3BDrill_Depth%3D0.025400000000000002%2Bmeter%3BDrill_Point_Angle%3D2.059488517353309%2Bradian%3BLead_in_Countersink_Angle%3D2.0943951023931953%2Bradian%3BList_e4drDdCvFBsU55%3DDefault%3BList_zdDJcPXnE3VFYu%3DDefault%3BModelled_Threads%3Dfalse&renderMode=0&tangentEdgeStyle=1&rightPanel=configPanel&uiState=67421884329729325bd4ab3f
@Oliver_Couch - Here is a link to newer version, NPT tap & die models (male & female), 1/16" to 6" dia. They are to ASME B1.20.1 standards. I may add larger sizes later, but this is a start. After talking to him, I'm going to work with @EvanReese on his F.S. after Thanksgiving holiday. Tell me what you think.
Still a few minor issues to work through, to make it F.S. ready, but all configurations seem to work properly.
It is a bit tricky to get all the configurations to work, seems like there is always one problem child.
https://cad.onshape.com/documents/8fbdf876d0f9f00555329d0f/w/977ac79725285939082478f9/e/3783c0332b21be972e7277d8