12 Replies Latest reply on Jul 25, 2018 1:31 PM by Maha Nadarasa

    Properly Molding

    Maha Nadarasa

      We have bought a plastic Food Container Set. Even though we tightly close the lid it slips and comes out. Where is the problem in molding? There is no problem with mini containers only big containers give trouble.  

       

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        • Re: Properly Molding
          Steven Billeter

          Exactly how is this a SolidWorks issue? If you owned the company that makes the containers and they used SolidWorks this might be a question for the Forum. Otherwise, unless you have created models of these in SolidWorks this is not an issue for this forum. Is this a joke?

          • Re: Properly Molding
            Paul Salvador

            ..I suggest activating the "Return it" add-in.

            Imreturn3.png

            • Re: Properly Molding
              J. Mather

              Q1. Is this behavior observed even with empty container?

              Q2. If not empty - are the contents going from hot to cold or from cold to hot?  (or neutral room temperature)  Have you run a thermal analysis?  (Be sure testing is done without influence of holding in hand.)

              Q3. What is the time period of observing the behavior.  Have you tracked the change in atmospheric pressure during the observation?

              Q4. Is the reseller unable to answer your questions?

              Q5. Is this OOTB observation, or have you adjusted original parameters by running in Microwave Oven or Dishwasher?

               

              More information is needed.

              Can you Attach your assembly here so that others can test?

                • Re: Properly Molding
                  Maha Nadarasa

                  Q1. Is this behavior observed even with empty container?

                  Yes

                   

                  Q2. If not empty - are the contents going from hot to cold or from cold to hot?  (or neutral room temperature)  Have you run a thermal analysis?  (Be sure testing is done without influence of holding in hand.)

                   

                  Food is filled into container is only at a room temperature. Neither hot food nor dishwasher washing is done because it can release harmful chemical into food from container. 

                   

                  Q3. What is the time period of observing the behavior.  Have you tracked the change in atmospheric pressure during the observation?

                  No

                   

                  Q4. Is the reseller unable to answer your questions?

                  This is a cheap item. Going for a complaint is not worth. 

                   

                  Q5. Is this OOTB observation, or have you adjusted original parameters by running in Microwave Oven or Dishwasher?

                   

                  More information is needed.

                   

                  Can you Attach your assembly here so that others can test?

                   

                  This plastic food container set is bought in a local store. I see there was a problem in modeling that is why lid does not close properly. I do not have any assembly file. I searched in YouTube to find out whether there is any similar item so far nothing found.    

                • Re: Properly Molding
                  Glenn Schroeder

                  Check this product.  I can't promise better quality, but it will definitely cost more.  On the other hand, I believe they do have a pretty good warranty.

                  • Re: Properly Molding
                    John Stoltzfus

                    If you want a good product buy Tupperware, like Steven Billeter mentions, how is this a SW question, are you planning to build a set of molds and compete with a better product??

                    • Re: Properly Molding
                      Newell Voss

                      Not sure how this relates to SW but,

                      To answer your question "where's the problem in molding", you would need to know more information you probably dont have access to.

                      It could be the initial design itself (unlikely if the scaled down version works). It could be the tool, maybe they need to add in some windage or rework areas to adjust for warp/shrink. It could be the process from a cooling/ post mold standpoint. It could be a material batch issue that wasn't caught..

                      It could also be user error; (rectangular shape/ unideal storage conditions/dishwasher use/microwave use/ etc..)

                      That being said, what are you trying to gain by this question from a CAD perspective? looking to design something better?

                      Research plastic part design, look into common "hold" solutions like crush ribs and other features that mimic what the tupperware uses for a better understanding.

                      It appears you are littering the forum with a question more suitable for the manufacturer. This could demote other users  SW-relevant questions that deserve more attention.

                      • Re: Properly Molding
                        Paul Risley

                        I don't particularly understand how a cheap set of plastic containers is expected to live up to any expectation. As far as this being a solidworks question or not, kind of. The question being posed is vague and very misleading.

                        Are you asking if there is an issue with the mold? Probably so.

                         

                        We design pultrusion catch lip dies, once they have .002-.003" of wear parts need to be replaced otherwise the parts no longer catch properly.Image below is of 2 of the parts.

                        Capture.JPG

                        I do not make plastic containers nor do I make molds for them, but I am going to assume the product you have was ran towards the end of the lifecycle for the die prior to inserts being replaced and the mold being re-finished. Or the company that makes it is just on the cheap and says good enough.

                         

                        I would say try a different brand.

                        • Re: Properly Molding
                          Matt Lombard

                          You need undercuts on both parts, so they don't slip past one another when the lid is on. The undercuts need to be small enough that you can still get them out of the mold, but large enough to cause sufficient friction on assembled parts. Take parts you like, cut sections in them and measure them. And pay attention to the materials used, they are important for friction grip.