12 Replies Latest reply on Sep 5, 2017 1:21 PM by Stefan Fredriksson

    Gated Pattern Making

    Aurelio Hernández

      Hello,

      I have done some searching on the subject but have not found any good tutorials on creating/designing permanent patterns (gated, split etc). I am interested in learning how to create a permanent aluminum pattern to be used to create impressions in sand molds. My question is, using the 3D models of finished or cast components how then do I model a permanent pattern?

       

      If anyone has any insight or helpful direction I would appreciate it.

       

      Thank you

        • Re: Gated Pattern Making
          Rob Edwards

          Make a new part

          Insert the part you want, just select solid bodies

          you can then linear pattern your solid body and your other bits merging them into one

            • Re: Gated Pattern Making
              Aurelio Hernández

              Rob,

              Thank you for your response however I am needing something more along the lines of the patterns in the included picture. I need to take a model and depending the parting plane create patterns that can be used to create impressions. I need to determine how to split the models, sometimes following specific edges, and then attach these split models to plates (probably as easy as it sounds). I know there is some application specific programs out there but if I can get by with using SW I will.

              slide_15.jpg

                • Re: Gated Pattern Making
                  Mike Lambert

                  Flat parted patterns like this are easy.  Once you have your pattern model with shrink and coreprint clearances all you have to do is split the body with a plane.  Then you can draw the board that it mounts to and combine them.  From there you can add the gating and locators.

                   

                  If the pattern is not flat parted then typically you can model the parting as blocks that can be added or subtracted from the pattern plate.

                   

                  I work for an aluminum foundry and we design all of our tooling in Solidworks.  It can definitely be done without any other software.  We design airset tooling, greensand tooling, permanent molds, low pressure permanent molds, shell coreboxes and SO2 coreboxes.

                   

                  Mike

                    • Re: Gated Pattern Making
                      Aurelio Hernández

                      Mike,

                      I am most interested in the not flat parted patterns because a lot of our more complex parts have parting lines that follow varying edges. Can you elaborate on "modeling the parting line as blocks?"

                       

                      Thank you!

                        • Re: Gated Pattern Making
                          Mike Lambert

                          Sure, take look at this picture, the gray would be a simple casting and the green "block" would be a separate solid that would represent the offset parting for the ear on the casting.  I would draw the block and then Indent the gray casting into the green so it would have the casting shape on the inside of it.

                          pic1.JPG

                          Then I would split the pattern with a plane that is the main parting plane.  Next I would draw the pattern boards and combine those to the casting shape for the cope and drag.  Then I would copy the green "block" body and then on the cope side I would just combine the block to the cope pattern and on the drag side I would subtract the "block" from the drag pattern.

                          pic2.JPG

                          Once you have the cope and drag with the parting you can add the clearances and fillets.  I know this is a really simple example but the system of how it is done can be used on difficult parts as well.  I hope this makes sense.

                           

                          Mike

                            • Re: Gated Pattern Making
                              Aurelio Hernández

                              Mike,

                              Great example I completely follow you other than the one note "Indent the gray casting into the green so it would have the casting shape on the inside of it." If the casting is recessed into the green block at all wont this reduce the thickness of the "ear?" Why do you not just make the block flush with the ear surface? I realize this is just an example but I was curious about this note.

                               

                              I have another question if you wouldn't mind shedding some light on, have you ever worked with models that do not have draft and how do you handle patterns for such models. We at times receive non-drafted models from customers and I wonder if I would need to spend time trying to edit the model, which may be tricky since most will be imported files, or create the patterns based on these non-drafted models and then try to manipulate the patterns to include draft on the correct faces.

                               

                              Thank you

                                • Re: Gated Pattern Making
                                  Mike Lambert

                                  There is always more than one way to do things like this.  The block should be flush to the ear and on this example it would be easy to just make the block match the profile of the casting but on more complicated models it would be hard to try and match the green block exactly to the casting.  So normally I just run the block into the casting and then indent it so I have the casting shape on the side of the block.  Another way is I guess you could skip the indent command on the side of the green block but then instead of combining the drag pattern and the drag board first, you would have to subtract the green block from the drag board first and then combine the drag board and the drag pattern. 

                                   

                                  The majority of our customer models don't have draft, and we prefer it that way.  Normally the customer doesn't have enough foundry experience to know how we prefer to make the part so if they add draft a lot of times it is in the wrong direction.  Most of the time we take our customer imported models and we will model on top of what they have with a separate solid body and add draft, machine stock, fillets and anything else we need to so that it is castable.  Our main cast model will have everything needed for the pattern and cores so that when we save the bodies into pattern and core parts we only have to do the parting and tool design.  This way the tooling always matches the cast part that the customer is expecting.

                                   

                                  Mike

                          • Re: Gated Pattern Making
                            Rob Edwards

                            ah that looks like nice

                        • Re: Gated Pattern Making
                          Mike Lambert

                          That's a pretty broad question but I'll answer what I can.  Typically we start with a part model that represents the casting.  We add machining features to it and either make a configuration for it or we just put all of the machining features in a folder at the end of the tree that we suppress or unsuppress as needed.  If the part require cores we also model them in this part file.  Then we right click on the bodies in the Solid Body folder and save them to new files that we call pattern or core, depending on what it is.  The pattern file would have the casting body and all of the core bodies.  The core file would have individual core bodies.  We then add our shrink and coreprint clearance.  At that point, depending on the type of tooling, we create the parting surfaces and develop the pattern inserts or pattern tooling.  In the corebox file we add the shrink and then develop the corebox around the core and eventually use either subtract or indent to make the cavity of the core.  If the coreboxes or patterns are complicated sometimes we would have assemblies with the ejection systems or mounting systems.

                           

                          I hope that helps!

                           

                          Mike