Community
Inventor Forum
Welcome to Autodesk’s Inventor Forums. Share your knowledge, ask questions, and explore popular Inventor topics.
cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

Models of standard Bottle Threads

11 REPLIES 11
SOLVED
Reply
Message 1 of 12
lheavner48
18199 Views, 11 Replies

Models of standard Bottle Threads

Hello All,

 

I'm working on some bottle concepts and I have a need to model standard plastic bottle threads. These threads are designated by a diameter in mm and how many threads are on the bottle. Example: 33-400  The 33 is the diameter and 400 refers to a single turn of the cap. Manufacturers like Aptar make bottle tops of various types to fit this spec. I happen to be looking at dispensing lids (think Heinz Ketchup bottle). While I've found specs for Major diameter, Minor diameter and TPI, I have found precious little that describes the thread shape itself. I've tried to reverse engineer a sample thread from... you guessed it.. a Heinz Ketchup bottle. I feel that my venier caliper and micrometer are not doing this effort justice. 

 

Does anyone out there have a DWG file or Inventor model of the thread profile? 

 

I'm using the coil command to create the thread on the bottle neck. It works okay. An issue arises with the thread termination. The threads on the bottle itself "chamfer" into the bottle neck. While I don't think I can do this with the coil command itself, I was interested if anyone has been able to create the "lead-in" for the plastic thread. I would be interested in any suggestions.

 

I hardly consider myself to be an Inventor expert. So, if you have discovered alternatives to modeling the thread I'm all ears.

 

Thanks for your consideration!

11 REPLIES 11
Message 2 of 12
JDMather
in reply to: lheavner48

The lead in can be modeled with coil (enter a taper angle for the helix).

 

A while back someone posted a url for standard dimensions for these threads - a Google search might turn something up.


-----------------------------------------------------------------------------------------
Autodesk Inventor 2019 Certified Professional
Autodesk AutoCAD 2013 Certified Professional
Certified SolidWorks Professional


The CADWhisperer YouTube Channel


EESignature

Message 3 of 12
lheavner48
in reply to: JDMather

Hi JD,

 

Experimenting with Taper angle on the thread design itself yielded a taper for the coil helix itself. Very interesting results... but not a thread lead-in. Again, I may be using the wrong options in the coil command itself. I am using Inventor Version 10.

 

I have attached what I've been able to Google regarding standard bottle threads. This is probably the best reference I've found and it comes from the Society of Plastics Engineers (??). However, it still doesn't actual detail the thread profile.

 

I may be picking a nit here, but I come from an Aerospace background and a fine thread and a "J" fine thread make a big difference in holding an aircraft engine together. The only difference being a radius condition on the "J" thread itself.

 

Many Thanks for your quick reply.

Message 4 of 12
JDMather
in reply to: lheavner48


Experimenting with Taper angle on the thread design itself yielded a taper for the coil helix itself. Very interesting results... but not a thread lead-in.


Attach the ipt file here.

 It actually takes 3 Coil features.
One for the main thread pitch and two for the lead-in and out.

 

Bottles.png

Bottle Thread.png


-----------------------------------------------------------------------------------------
Autodesk Inventor 2019 Certified Professional
Autodesk AutoCAD 2013 Certified Professional
Certified SolidWorks Professional


The CADWhisperer YouTube Channel


EESignature

Message 5 of 12
lheavner48
in reply to: JDMather

That is perfect....

 

What did you use for the thread profile sketch itself?

 

As I understand, your response and images... You used a 400 series main ptich (1 turn). Afterwords, you projected the thread profiles to sketch planes used a taper angle with a partial pitch 1/8 turn to create a lead-in and lead out.

 

Great model of a Gatoraid bottle.

 

Larry H. 

Message 6 of 12
JDMather
in reply to: lheavner48

Oops, don't pay attention to those numbers in the browser.
That was an example a student did and it didn't look correct so I moved the top out of view (notice that you can't see the thread in that image - but he was trying to reproduce steps as I showed in right image on my example).

The bottle on the right and with the close-up is one that I did.


-----------------------------------------------------------------------------------------
Autodesk Inventor 2019 Certified Professional
Autodesk AutoCAD 2013 Certified Professional
Certified SolidWorks Professional


The CADWhisperer YouTube Channel


EESignature

Message 7 of 12
lheavner48
in reply to: JDMather

Hi JD,

 

I can't read the numbers in the browser anyway..  Do you have a detail of the thread profile? or a look at the browser for the correct model?

 

I believe that this will do it. I did go to your web site at the college, but didn't find anything specific in the tutorials.

 

BTW: Great job with the tutorials and all the work your doing with the students. It looks impressive.

Message 8 of 12
lheavner48
in reply to: JDMather

Hi JD,

 

I've been pretty busy lately but I wanted to post an Inventor file that I was using to model Threads on a bottle neck per your suggestion.  I have a pictue of the threads below.

 

I not sure that I have the thread profile right. I think that I didn't use the coil command correctly either. Any help is appreciated.

 

 

 

 

Threads on a bottle neck

Message 9 of 12
lheavner48
in reply to: lheavner48

Well with help from JD and a little internet persistance, I've figured out threads. Technically this is referred to as "neck finishes" by SPI. Neck finishes are defined by SPI. While the thread profile itself is defined by ASTM standard (ASTM D 2911). ASTM D 2911 is available for purchase on the internet for about $40 USD.

 

I have attached a HTML file, found on the net, that defines the neck finishes. I have also included a pic of the 22-400 neck finish that I modeled in Inventor. I choose a "M-style" thread that is common to plastic bottles and is referred to as a "buttress thread". I'll leave it to the reader to tell us why it has this name. Hint: think Cathedral of Notre Dame. 

 

As far as the operations for modeling in Inventor, it's pretty much a snap. You'll need 3 coil commands; main thread, lead-in, lead-out. It takes some experimentation, but use the "Pitch Revolution" option for the main thread. For the lead in and lead out use a negative taper and a fraction of a revolution. Inventor does the rest. (Thanks JD!) Remember...Rightee tightee, leftee loosey.

 

JD, I think that the thread profile used in your example isn't quite correct. The model itself is missing radii for the thread profile. I don't mean to be a stickler.. but as my first post indicated a missing radius makes a big difference in performance.

 

22-400 neck finish.png

Message 10 of 12
jburger3842
in reply to: lheavner48

tapering was being a bit...discontinuous for me... but one can:

1) make the first coil for the thread

2) draw a sketch of the thread profile on each face at the end of the first coil (pitch and rev.)

3) create another axis a bit closer to the side where the coil ends are, by making a work plane a bit that direction towards the side where the coil ends are, and drawing a line up the center, parallel to the axial direction axis of the container.

4) use a coil each for lead in and lead out profiles sketched earlier, draw a less than one rev. coil around that new axis.  

5) you can adjust where the lead in/lead out end up by adjusting that work plane dimension for the new axis if need be/Lord Willing, add fillet(s), etc. after perhaps

6) extrude a circle through the neck to "clean up" areas if/where the coil feature crossed through the inside of the neck.

 

You can see if anyone on google (like a plastic container mfr.) has posted the SPI neck finishes, or get the ASTM (purchase or perhaps library...)

 

“All that the Father gives Me will come to Me, and the one who comes to Me I will by no means cast out. For I have come down from heaven, not to do My own will, but the will of Him who sent Me. This is the will of the Father who sent Me, that of all He has given Me I should lose nothing, but should raise it up at the last day. And this is the will of Him who sent Me, that everyone who sees the Son and believes in Him may have everlasting life; and I will raise him up at the last day.””
‭‭John‬ ‭6:37-40‬ ‭NKJV‬‬
http://bible.com/114/jhn.6.37-40.nkjv

thanks and love/thank/praise/bless/glorify God/Lord,
Best,

http://Bible.cc
http://www.Bible.com
"For God So Loved the world, He Gave His Only Son..." 

Message 11 of 12
dmq31175
in reply to: jburger3842

Why you mentioned about spi standard in this activity?

Message 12 of 12
jeffg28CLY
in reply to: dmq31175

Different "SPI."

SPI Standards = Society of the Plastics Industry, and their standards for this kind of bottle thread.

Can't find what you're looking for? Ask the community or share your knowledge.

Post to forums  

Autodesk Design & Make Report