7 Replies Latest reply on Oct 3, 2014 2:28 PM by Daen Hendrickson

    step-by-step assembly drawings -- best practice?

    N. Ritchey

      i'd like to hear some input on your suggested method for creating a "step by step" assembly drawing.


      what i'm creating is an assembly drawing for a large assembly. there are many many parts, and it is a complex and resource-heavy model. lightweight, speedpaks, whatever the thing is a hog and it continually pushes the boundaries of 2014's resource monitor.


      i've broken down the assembly process into 5-6 steps.


      i want to illustrate each step on its own page. so the "drawing" is 6-7 sheets including a cover page, and each assembly step has its own page.


      each assembly step also has its own exploded drawing.


      WHAT I DID: i used configurations within the assembly file. the benefit here is that, when working in the earlier stages of the assembly process, the model is easier to work with because you can purge unloaded steps. of course the downside is that the file is difficult to handle both on disk and in SW. the drawing file created is a large file and it also difficult to handle in solidworks. you can purge configurations in a part file, but in a drawing all part files must be loaded.


      WHAT I'VE HEARD: is to use display states instead of configurations. the benefits i see will allow the drawing to consume less memory (only one configuration is loaded). but it seems more complicated to perform and execute. instead of selecting a config, i now i have multiple exploded states and multiple display states, and they cannot be linked as far as i'm aware (?).


      OTHER IDEAS: a new .SLDDRW file for each configuration of the assembly? this is also cumbersome, but i feel like it might be a bit easier to manage multiple sheets as opposed to multiple display states AND multiple explode states


      OTHER OTHER IDEAS: multiple .SLDASM files for each stage of the assembly. i am against this idea for the obvious reasons. adding a new part at an intermediate step is difficult enough using "configure components". i couldn't imagine having to manually keep track of all of that information throughout multiple files for the same assembly. actually, this sounds like a really bad idea.


      please, discuss! i want to hear how others manage this type of drawing.

        • Re: step-by-step assembly drawings -- best practice?
          Jeff Mirisola

          In previous roles, I used the configuration idea. Now, I use Composer.


          I'm curious, though. How are you able to break down what sounds to be a huge assembly into 5-6 assembly steps?

            • Re: step-by-step assembly drawings -- best practice?
              N. Ritchey

              i am not familiar with composer, i will look into that.


              i'm not sure how to explain "large assembly, few steps". a lot of it has to do with the complexity of some of the parts (circuit boards). one step of the assembly involves adding 3 circuit boards to a chassis. but those circuit boards, even in their "stripped down, lightweight" versions contribute a lot to the physical size of the SLDASM file. much of the complexity also comes from the large number of fasteners, which are displayed exploded in the assembly drawings and also must be present in the model for our drawing BOMs. the only other excuse i have is that there are a large number of 3rd party STEP files from our suppliers involved and some of them are not very efficient.


              on that note, can anyone recommend a resource for general tips or "best practices" in what an assembly drawing should look like? not to tip my hand, but i'll just say that it wouldn't hurt for me to get some ideas and inspiration on what my final product should look like, along with a refresher on what is and isn't important.

                • Re: step-by-step assembly drawings -- best practice?
                  Jeff Mirisola

                  The circuit boards I get; been there, done that. The fasteners, however, shouldn't be all that complex unless you're actually modelling the threads. If you are, I'd question the reasoning behind it. Also, is it necessary to show every fastener exploded?

                  As for the .step files, do you not convert them?


                  Assembly drawings are what you want them to be or, more to the point, what your assemblers want/need them to be. When it comes to how they look, I go for "not busy", simple, easy to understand.

                    • Re: step-by-step assembly drawings -- best practice?
                      N. Ritchey

                      90% of the fasteners are out of the toolbox in the simplified config (no threads cuts no cosmetic threads), the remainder are 3rd party-supplied models (whether SLDPRT or STEP). some of the fastener models came from 3rd party suppliers, and some of them are "blanks" as i call them (self-modeled dummy placeholders)


                      for the sake of numbers here is what i've ended up with:

                      the assembly file is ~75 MB on disk

                      the associated drawing file is ~130 MB on disk


                      the problem is that with the model you can purge unused configurations -- in the drawing, ALL configurations are loaded, so it's like having 5x 75MB models loaded into memory.


                      what do you guys think about multiple SLDDRW files? one for each config. of the model (i.e. splitting a single 7 page dwg into 7x single page dwgs?)


                      jamil, i actually have quite a few subassemblies active in the master assembly (one of the reasons i can boil the top-level assem to 5 steps). this was a relatively new tactic i've started using and i do quite like that.

                        • Re: step-by-step assembly drawings -- best practice?
                          Daen Hendrickson

                          A few other observations about large assembly efficiencies:


                          1> make sure your fasteners / hardware are as simplified as possible.

                               - No threads modeled, no knurling, etc.

                               - For vendor supplied (McMaster), I often create a second configuration named "Simplified"

                          2> pattern the fasteners as much as possible.

                               - Locate one with mates (screw, lock washer, flat washer)

                               - Locate the rest with patterns / mirrors

                                    - Feature Based Pattern is your friend (just click on your hole wizard holes and watch the magic)

                          3> Pattern and mirror as many of your parts as possible

                               - Patterns are generally much less resource intensive

                               - Your assembly tree is smaller

                          4> Use dimensions to locate components as the LAST resort.

                               - Dimensions are the most resource intensive method of locating

                               - Use mates, symmetry, patterning first

                               - This should apply at the part level as well as the assembly (design intent)

                               - Mate "elemental" feature as your first choice

                                    - "elemental" refers to the part origin, front, top, right planes

                                    - This also greatly reduces the amount of broken mates when part geometry is edited

                               - If you have multiple items located a common distance create a plane at that distance and mate the components to the plane.

                               - If you have a common dimension applied in multiple places, use a global variable

                               - Review your models for redundant mates and delete / suppress

                                    - For instance, you might mate something parallel to orient it so that the dimension will default

                                      to distance instead of angle. Once dimensioned, the parallel mate becomes redundant.

                          5> Simplify your assemblies by reducing mates/dimensions/etc in the top level

                               - As Jamil noted, push as much as you can down into sub-assemblies


                          Several of these things are subtle in their individual performance gains. But they can make all the difference in large assemblies. Your model will open faster and generally be more stable.



                  • Re: step-by-step assembly drawings -- best practice?
                    Jamil Snead

                    I used to use the configuration method, but as you say it was a drain on the system. Ever since they started allowing multiple exploded view within a single configuration now I use the display state method. But I know what you mean about the lack of linking, you have to know which display state corresponds to which exploded view.


                    Another option (which I am starting to think is actually the best) is to take advantage of subassemblies. Say you have 5 steps, the top level assembly with the final explode could be step 5. Then have a subassembly in there that represents the completed step 4, which contains a subassembly with the completed step 3, etc. I understand that you want to show all of the parts on the BOM, so in that case in the configuration properties for the subassembly, under Bill of Materials Options, you can select Promote, and the subassembly will not be listed in the BOM, instead all of its parts will be listed in the top level assy as if the subassembly were dissolved.