33 Replies Latest reply on Aug 23, 2017 12:25 PM by Paul Risley

    How's my mailbox? (revised)

    Eric Eubanks

      I've asked this before. I've made several changes since then. How does it look now?

      Now would it be best to work on drawings or molds for the mailbox next? Or does it even matter what I do first?

        • Re: How's my mailbox? (revised)
          Doug Seibel

          You may want to get into the habit of using the Interference Detection tool...your door is still interfering with the mailbox body.

           

          The flag is improperly assembled into the hole, resulting in interference.

           

          The flag hits the mailbox body when it is down (interference).

           

          The hinge pin is improperly assembled into the hinge, resulting in interference.

           

          The holes in the hinges are not correct for the fastener you are using, resulting in interference and a really ugly fit.

           

          Your hinge assembly interferes with itself.

           

           

           

          Do an Interference Detection, fix all the problems it shows.

           

           

           

          Your fastener is doing nothing, as you have it designed.  It doesn't even go into the door (which is too thin to thread and get much life expectancy out of).

           

          The fastener should go completely through the door and into a nut on the other side, or the fastener should be changed to a button-head screw that is on the INSIDE of the mailbox and threads into the metal hinge.  What you have, just will not work.

           

           

           

          You have a fastener that is just hovering inside the mailbox...

           

           

           

          The design of your hinge will allow the door to move side to side...1" of side to side travel...when the door is open.

            • Re: How's my mailbox? (revised)
              Eric Eubanks

              I did an interference detection and it showed no interference. I don't know what went wrong there.

              • Re: How's my mailbox? (revised)
                Rick Becker

                Doug Seibel wrote:

                 

                You may want to get into the habit of using the Interference Detection tool...your door is still interfering with the mailbox body.

                The flag is improperly assembled into the hole, resulting in interference.

                The flag hits the mailbox body when it is down (interference).

                The hinge pin is improperly assembled into the hinge, resulting in interference.

                The holes in the hinges are not correct for the fastener you are using, resulting in interference and a really ugly fit.

                Your hinge assembly interferes with itself.

                Your fastener is doing nothing, as you have it designed. It doesn't even go into the door (which is too thin to thread and get much life expectancy out of).

                The fastener should go completely through the door and into a nut on the other side, or the fastener should be changed to a button-head screw that is on the INSIDE of the mailbox and threads into the metal hinge. What you have, just will not work.

                You have a fastener that is just hovering inside the mailbox...

                The design of your hinge will allow the door to move side to side...1" of side to side travel...when the door is open.

                 

                Nice job Doug.

                I'm sure you spent more time typing out your answer than you did finding the problems.

                • Re: How's my mailbox? (revised)
                  Eric Eubanks

                  Will I be able to keep the screws in their current locations if I make the door thicker? That would just make it easier That moving the holes and screws to the other side of the door.

                  What is the advantage of a button head screw vs a flat head?

                    • Re: How's my mailbox? (revised)
                      Doug Seibel

                      I doubt that you will have much success with the "threads in fiberglass" approach, no matter how thick you make the fiberglass.  (I can pretty much guarantee that you will not have success with that approach.)  Perhaps you should look into changing the fastener to a Binding Post Screw or Chicago Screw.  That would give you a nice clean look on the inside of the mailbox.  (And your hole in the hinge is currently for a binding post screw, you just need to size the holes in the mailbox for the "post" of a binding post screw and show the fastener as a binding post screw.)

                       

                      https://www.chicagoscrews.com/images/samples/Black-Oxide_MG_2111.jpg

                       

                      The reason for using a button head screw is that your door is far too thin for the flathead to work (when having the fastener's head be on the inside of the mailbox and the threads be in the hinge).

                    • Re: How's my mailbox? (revised)
                      Eric Eubanks

                      Is it normal to have this many interferences?

                        • Re: How's my mailbox? (revised)
                          Doug Seibel

                          Depends...

                          When you have someone that either doesn't know what they are doing or isn't paying attention to what they are doing, and obviously isn't doing much to double-check their work, then yes...it is normal to see this many problems in a design.  But as a "general rule", no...having this much be wrong in a design that the person thinks they have properly and fully checked for fit & function is most certainly not "normal" and not acceptable.  And nothing like this should ever make it out of design and into manufacturing.  One of the main advantages of solid modeling and relational/parametric CAD design software is to make it easier to design something that actually works when built as designed.

                            • Re: How's my mailbox? (revised)
                              Eric Eubanks

                              Is it normal for someone who is experienced with solidworks to have this many interferences when you check for the first time?

                              I just want to know is it better to prevent them from happening in the first place or just make the assembly and fix interferences later.

                                • Re: How's my mailbox? (revised)
                                  Doug Seibel

                                  No, it should not be normal for an experienced Solidworks user to put out an assembly with this much wrong in it.  They should have developed a design process that leverages the capabilities of the software to prevent such errors from occurring, and they should have developed design-check habits that catch any problems.

                                   

                                  It is far better to prevent them from happening.  Doing it right the first time is the fastest, most efficient and productive method.  It always takes longer to do something wrong and then fix it, than it does to just do it correctly the first time.

                          • Re: How's my mailbox? (revised)
                            Steven Mills

                            Three things with the screws you may want to get into the habit of/change.

                             

                            1. Remove the modeled thread. You get 20 or more of those circled splines in an assembly, the entire model really slows down.

                            2. The visible sketches in the screw. Hide them at the part level, or your assembly becomes a grey mess of lines when you view sketches at the assembly level.

                            3. Why are you putting countersink screws into square-cut holes?

                              • Re: How's my mailbox? (revised)
                                Eric Eubanks

                                1. Remove the modeled thread. You get 20 or more of those circled splines in an assembly, the entire model really slows down.

                                What's that? Cosmetic threads?

                                 

                                2. The visible sketches in the screw. Hide them at the part level, or your assembly becomes a grey mess of lines when you view sketches at the assembly level.

                                I didn't even notice that. I deleted the screws anyway. They're too short.

                                 

                                3. Why are you putting countersink screws into square-cut holes?

                                They just look like they fit together best.

                              • Re: How's my mailbox? (revised)
                                Eric Eubanks

                                By the way. This is my progress on the mailbox. I still haven't done anything with fasteners yet besides delete the old ones that were too short. All interferences with doors open and closed are fixed. There is still one interference if you put the flag down, but I'm going to keep it because the flag will hit the main body of the mailbox and not go too far down.

                                  • Re: How's my mailbox? (revised)
                                    Doug Seibel

                                    Now the trickier little problems can be found...

                                     

                                    I was pretty sure that this would end up being a problem area.  While your door does not have any more interference when it is in the closed position, it does have interference as soon as you start to open it...

                                    Both doors have the same problem, of course.

                                     

                                    Also, the "lip" around the door is not modeled to have uniform clearance around the mailbox body.  That just looks...sloopy.  (And it is the reason for the interference when opening the door.)

                                    This is caused by how you dimensioned the sketch for the door...

                                    The 11.35 dimension should not be a driving dimension.  It really doesn't even need to be there.  (I don't know the reason for the 6.00 dimension either.  It certainly doesn't "center up" the part on the origin.  Not sure what purpose that dimension is serving for you.)

                                     

                                    Here is the dimension the sketch needs...the distance from the center of the arc to the bottom straight line...

                                    And that dimension needs to be a value of 4.54311931in...

                                     

                                    Fixing that...fixes the interference problem.  Because now the door's lip has uniform clearance around the mailbox body.

                                     

                                    The one other thing that I see as a glaring issue with the design at the moment...is that I see nothing that keeps/holds the door shut.  What is your plan for that?

                                     

                                    I'm also not seeing any provision for mounting it.  Not sure what the plan is for that either.

                                  • Re: How's my mailbox? (revised)
                                    Rick Becker

                                    Eric,

                                    Would you be so kind and give us a bit about your background? How old are you? Where are you attending classes? What degree you are majoring? The name of this class? Any experience in mechanical areas?

                                    I really believe that the help you received above is worth much more than the cost of the class you are taking. You do need to apply what is being taught and that may necessitate starting over.

                                    In the real world, starting over is done. All too many times. The good news is the second time is always faster and better as long as you apply what you learned the first time.

                                      • Re: How's my mailbox? (revised)
                                        Eric Eubanks

                                        I'm attending Davis applied technology college in Utah. I'm 24 years old. I made a mailbox once before, but I started over already. I haven't had any job experience in mechanical areas. I just have one class at a time and its mostly focused on Solidworks. I've also done some projects with autocad. I'm not getting a degree in anything. I'm just going to school to learn Solidworks. My current class in on composites which is why the mailbox is fiberglass. We don't have any classroom instruction here. The instructors are just here to answer our questions.  Anything else you want to know?

                                          • Re: How's my mailbox? (revised)
                                            Rick Becker

                                            Thank you for the reply.

                                            I am inspired by you and the way you are steering you ship.

                                             

                                            I have seem many designers come and go thru the years.

                                            From my experience, there are two ways people come to CAD design.

                                            Either they learn the CAD program and become super-users or they are manufacturing mavericks, tool makers, machinists or the like that then learn a CAD program.

                                             

                                            The most successful designers have  all come from the second category.

                                            I can teach a CAD program to anyone, I can;t teach manufacturing experience, it must be earned.

                                             

                                            I would suggest some classes in mechanics or manufacturing focused on hands-on learning.

                                             

                                            I mean no disrespect at all Eric. I really believe any designed will benefit from hands-on manufacturing experience.