×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Ball and socket snap fit
3

Ball and socket snap fit

Ball and socket snap fit

(OP)
I would like to know if anybody has an idea how to calculate all the parameters needed to properly design a ball and socket snap fit.
I have searched on the internet but I did not find any clear equation that explains the relation among the ball diameter, the socket diameter, the opening width and the material properties (I will use the ERTALYTE).

Thank you in advance for any proposition.

RE: Ball and socket snap fit

I don't think you're going to find anything online to give you the exact answer. Every situation is different based on different materials, different surface finishes, different sizes, how tight you want it to be, and the features of the socket (whether it is split or solid, how much rotation you need, and how easily/tightly you want it to move)

You are probably going to have to figure it out for yourself through trial and error with some prototypes.
If you are machining the parts, start with it overly tight, and then you can remove material a little bit at a time until you get the fit you want.
If you are molding the parts, start with it overly loose, and then you can remove material from the tool (making the part larger) until you get it where you need to be.

I can tell you that it doesn't take much interference to get a real solid fit, usually only a couple thousandths depending on the overall scale of what you are working on.
Also, make sure you understand the tolerances of how the parts are going to be made. Again, a couple thousandths could make a big difference.

Good Luck.

RE: Ball and socket snap fit

(OP)
Thank you Eltron and sorry for posting it in the wrong forum

RE: Ball and socket snap fit

(OP)
MDGroup, thank you for your answer. If there is no solution, I will be forced to make it according to you advice.

RE: Ball and socket snap fit

This is a good reference for ball and socket: https://cdn.sparkfun.com/assets/home_page_posts/1/...

also, ertalyte is probably too brittle to do this with if you need a small part (low max strain). iirc ertalyte is similar to delrin af which you might be able to use in its place. just make sure you calculate max strain (including tolerances).

RE: Ball and socket snap fit

Try searching for a PDF from Ticona, called Design Calculations for Snap Fit Joints in Plastic Parts. It is probably very close to what has already been suggested.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read FAQ731-376: Eng-Tips.com Forum Policies: Eng-Tips.com Forum Policies to make the best use of these Forums?

RE: Ball and socket snap fit

(OP)
Thank you all, it is so interesting as reference.

RE: Ball and socket snap fit

use FEA. in the linear zone it's quite reliable, if you set the model correctly.

RE: Ball and socket snap fit

(OP)
Unfortunately, I don't have an license for ANSYS and it is so expensive.

RE: Ball and socket snap fit

use solidworks simulation, creo simulation or similar software then.

RE: Ball and socket snap fit

(OP)
Do you think that such simulations are possible using Solidworks? do you have any tutorial about that?

RE: Ball and socket snap fit

there are built-in tutorials, if you have solidworks simulation.
click options, add-ons, then check simulation. then look in help for them.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources