Gabi Jack's Blog

Second Tri-Valley SolidWorks User Group meeting coming up!

The second meeting of the Tri-Valley SolidWorks User Group will be held on June 18^th at the Holiday Inn Express in Dublin, CA, and  it’s looking really promising already, full of information and hands-on  learning opportunities. I’m really excited because many of the topics in the agenda fit perfectly with what I’m studying these days:  Smart Components, Smart Mates, Assembly Design Tables, among others. Also, our leader, Kenneth Barrentine will be presenting about Deconstructing a Vacuum Chamber. That sounds like something really interesting! Here, check out the rest of the agenda.

6:30pm - 7:00pm Registration, Food/Drinks

7:00pm – 8:30pm Automating SolidWorks using: Macros, Part Design Tables, Mating & Smart

Mates, Smart Components, Assembly Design Tables, KBE tools presented by Brian Titus

8:30pm – 8:45pm Break

8:45pm – 9:15pm Weldments, deconstructing a Vacuum Chamber presented by Kenneth Barrentine

9:15pm – 9:30pm Wrap Up, Prize Drawings, Next Meeting Agenda & Date

I’m bringing my laptop with me (of course!) and, perhaps, my little (digital) camera, to take a few pictures, or even film Kenneth’s presentation, as long as he doesn’t mind. I don’t promise anything on that one, though, just in case the presentation involves a hands-on exercise or requires our participation, in which case I’ll be too busy to hold a camera, but I’ll try.

So, if you are in the area that evening and want to check it out, you are certainly welcome to join. The more the merrier!  Just RSVP with Kenneth today.  See you there!

No Strings Attached

While going through the SolidWorks Training Manual on Advanced Assemblies, I ran into this little piece of information,  that  is so simple and easy, it kind of left me scratching my scalp, wondering how come I didn’t think about it before.  I’m talking about removing external references in a part document that was created or edited in the context of an assembly and made to reference the geometry of other components.

Why would you even want to do that? Well, you know that all external references that are established when you create a part in-context are going to remain with the part, and any change to the part done in the context of the assembly will also appear in the part document and affect other parts that it references to, causing them to change, as well.  If you wanted to use a part that was created in the context of an assembly  X inside a different, unrelated, assembly, say assembly Y,  then you need to first make sure that the changes made to assembly X  and/or any of its parts are no longer going to propagate to the part.  Sure, you can List External References in the part and choose to Lock All or Break All. If you lock them all, you stop the changes from propagating, but only temporarily, because they can be unlocked later on (either by you or the ever helpful co-worker).  Breaking the references, on the other hand, is irreversible and can’t be fixed. Changes will no longer propagate to the part, and this will definitely affect the design intent of your original assembly. So, it makes perfect sense when the manual recommends  that in order to produce a completely independent part you must  remove the external references instead, by following these very easy steps.

First, you should save the part document as a copy, so you can remove the external references from this copy without affecting the original assembly at all. It’s important to save the part as a copy of the original, because if you just Save As with a different name, this “new” part document will simply replace the original in the assembly.  Next, once you have created a copy of the part document, you will need to search its Feature Manager for  features that may have external references. You will be able to recognize them by noticing the symbols “->?” that are listed next to them.  These symbols tell you that the feature has an external reference, but that it’s out of context right now. All these references can be removed by editing the features and sketches that contain them to delete such references and add new ones. This is very easy to do with sketches, and lucky for us it’s very often that a sketch is the one that contains the external reference and not the feature itself.  Simply edit the sketch that has the external reference, click Display/ Delete Relations, and list all the relations that are external. Delete all the external relations and dimensions and  proceed to fully define the sketch, either manually or by clicking on Fully Define Sketch. This last step is a very important one and you should not forget about it, especially when removing external relations on geometry that was created by converting or offsetting entities, since they are left completely unconstrained, with no relations at all, after the on edge or offset relations are removed. Also remember that you should do this starting from the bottom of the feature manager and work your way up, to prevent the part from becoming disjoint.

Simple, isn’t it? Now if I could only find a way to do something similar to this for a part that was created by splitting another one or by saving bodies in a multi body part. But so far I can’t see a way this can be done, because there is no feature or sketch  whatsoever that could be edited in this kind of parts, so, even you break the references, to make it “independent” from its parent, it still pretty much works like a parasolid, an imported model that gives you no access or control over its history.  It would be great if there was a way to access that history or somehow add dimensions and relations, like when fully defining a sketch, in order to manipulate its already existent features, instead of simply adding new ones. Maybe I’m rambling here, so please forgive my ignorance if I am.  I’m still in SW2007, so I have no idea if perhaps this is already possible in SW2008 or will be possible in SW2009. It would be great! If I was to choose what is the one thing I like the most about working with SolidWorks, I would have to say that it is being able to access and manipulate the history of the part. The more of that history you can manipulate, edit, change and drive, the better! I love that feature manager! OK, now that I got that off my chest, it’s back to working on that manual.

On the way to the top

This week started with sad news about the recent passing of Mr. Eugenio Garza Lagüera, who was for many years head of the Tecnológico de Estudios Superiores de Monterrey, my alma mater.  He was a man of firm convictions; a real role model of integrity and excellence for all in the college community.  Deeply admired and respected by all of us. For some reason, ever since hearing about this, I’m finding myself thinking about those last days in college, about classmates, friends and people I haven’t seen in a long time, and that who knows if I’ll ever see again.

Around this same day, only twelve years ago,  a few friends and I decided to do something special in order to celebrate what we perceived as  the beginning of the rest of our lives.  The last week of college had felt like an anti-climax. The finals were over. All the projects have been presented, evaluated, judged and defended.  The rings had been chosen, ordered and paid for. All the pictures were taken. The diplomas were printed and signed, ready for the graduation ceremony, just a few days away. Many of us had already received job offers or had plans for continuing education abroad. But somehow, instead of feeling that tremendous joy and relief we always thought we would experience on that very last day of college, it just felt as if time had stopped and the world around us stood still.  “These are strange days”, my best friend said to me that night when he drove me home. “Tomorrow, we’ll do something grand”, he added with a boyish grin,  and then he left. He showed up at my place early the next morning. He wouldn’t say where we were going, but he told me to wear sneakers.  Three other friends were already in the car. Once we were all together, I learned we were headed towards Tepoztlán, Morelos. We were going to hike up El Tepozteco  mountain, to visit the ruins of the temples at the top. Now, at this point I think I should mention something about myself: I’m not and have never been a very athletic person. This hike was a first for me, but I’m really glad I went with them, because this experience changed something inside of me for the better.  You’ll see what I mean.

The first part of the way to the top seemed really easy.  There was a narrow path and even what resembled steps, probably made by the same people that built the temples, hundreds of years ago. We laughed and joked about how great hikers we were, as we danced our way to the top.  We wanted to run to the top and back, so we could have time to visit the market, have dinner and maybe go somewhere else before the day was over. My friend, who had been there many times before, simply smiled and told us to slow down. He said if we were lucky, we would make it back down before sunset and then we would visit the market, and grab a bite to eat on the way back to the city. We looked at him as if he had lost his mind, but soon enough we found out what he meant  by “before sunset”, as the narrow path and the steps disappeared before our eyes, and were replaced by rocks and slippery mud. Soon, we were down on hands and knees, painfully crawling our way up, our carefree hike turned into a slow struggle.

Every single step of the way, we had to keep focused, be careful where we put our hands and feet to avoid slipping down the steep. There was almost no place to stop and rest. We just had to keep moving because there were others coming behind us (it’s a very popular place) and there was hardly any room for anyone else. It was a hard way to the top, but wouldn’t you know it was also a very enjoyable one. Even while in fear of falling, we never lost our sense of humor, although our laughter often got confused in our screams of panic.  All in all, we still managed to laugh and joke as we helped each other, and even others, along the way.  As a great leader would do, my friend got the ball rolling, by coming up and down to give us a hand whenever we got stuck. Soon, all of us, even though inexperienced hikers, were doing the same for the people that came after us. It felt really good.

What we found at the top wasn’t really that impressive. The temple was small and lacking on the kind of splendor found in Monte Alban or Tenochtitlan. We climbed to the top of the pyramid and stayed there for a while, in silence, just taking in all the beauty and majesty of the valley and mountains around us. Then we slowly started on our way down, just as we climbed up, screaming and laughing all along the way.

I believe that, as it often happens in life, the best part wasn’t getting to the top, but simply the journey that took us there. Sure, goals are important. It’s important to have goals and to achieve our goals in a timely matter. It’s also important to never run out of new goals to look forward to, or else achieving the goal may end up feeling like the anti-climax we experienced.  However, as I found out that day, the real  gain is often that of what you learn in the process. It’s what you discover about yourself and others, the friendships and guidance that you find and share along the way, and how the journey transforms you in ways you never expected or even dreamed possible. A few months ago I started my own journey with a simple  goal: to update myself in order to become employable again. Never for one second I imagined just how exactly that journey would look like, what “places” it would take me through on the way to my goal, how difficult, painful, exciting, exhilarating and fun (all at the same time) it would be, and just how much it would transform me. Well, never for one second I thought I would be blogging about it, to begin with!

Many years have passed since that day. My best friend moved to Germany, I came to live to the United States. We lost contact with each other. Life has a way to do that to you. I never actually thanked neither my friend nor Mr. Garza Lagüera for the many ways in which they touched my life while I was still a college student, many years ago, although I’m forever grateful to them, just as I am grateful now to all those SolidWorks leaders, hikers and sherpas, that have helped me along the way and continue to make this “hike” unique and unforgettable. Thank you guys!  And thank you for reading all the way to this last paragraph. You are as patient as a saint! Sorry, no tips or tricks on this one, just a tribute to all of those people, like Mr. Eugenio Garza Lagüera, that are changing the world, one life at a time.

Entertaining Angels

As a female mechanical engineer, I always feel an overwhelming excitement whenever I find other women venturing in engineering, be it as professionals or students. I rejoice whenever I find women involved in science and technology, but particularly in engineering, since, in my country at least,  engineering is still a mainly male-dominated area, slowly opening up to women.  And women have so much to offer!

One of the things that I really like about this country is the encouragement that is being given to girls of all ages to pursue a career in science and technology.  I wish I had found that kind of support while I was a college student in Mexico!  Now that I’m a much older woman (a senile 34 year old), my college years way behind me, I often also wish that I could find a way to encourage other young women to become engineers, but right where I stand at the moment, in the middle of my own transition, there’s not really much that I can inspire or encourage others to. At least, that’s what I used to think, until recently, when I ran into this young lady at one of my son’s baseball games. I had noticed her once before. She was staring at me from the other side of the field, but it wasn’t until I put on my baseball cap that she came over to take a closer look. Yes, well, that particular day my husband and younger son had already taken the other baseball caps, and the only one left had the logo of the team my son was playing against, so I decided it was OK for me to look geeky in style and sport my SolidWorks baseball cap to the game. Anyway, she came over and asked me if I was Gabi, the blogger. Wow! Somebody reads this tripe! Well, it actually gets better than that, because she also told me that she’s a community college student, looking forward to transfer to a four year college to pursue a major in engineering. Then she said to me something that really made my day: she said that reading stories of engineer women like me and others has inspired her and, many times, kept her from giving up when times get tough.  Now, isn’t that something? To realize that this journey that I started for myself is actually helping others in their own journey is such an awesome thing… And it’s humbling too.

So, here it goes for this young lady, and for anyone else who might be interested. She asked me a question about Smart Fasteners and Hole Series (just my luck!). She wants to find a way to add  more than one smart fastener to a series of holes, to replace  a very long one that goes through several  parts in the assembly. After searching in the manual and online help and playing with it for a while to try to understand what she was talking about, I found that what she wants to do can actually be accomplished and is known as splitting a hole series. The tricky part is, however,  that you can’t really do this if the holes were created by an assembly feature. In other words, you can’t split the hole series if you used Hole Series command to create the series of holes. Does that make any sense? Each hole the Smart Fastener goes through has to be created by an individual feature, at the part level,for this to work.

So, imagine you have an assembly such as the one in the following image.

All the holes were created in the individual parts and then mated together in the assembly with concentric mates, so they would be aligned. If we use Smart Fasteners to apply some hardware to it, with this arrangement, we’ll get the following results. It doesn’t matter what hole we attempt to select, it will only allow us to select one.

If what we really wanted was to have a couple of short fasteners instead of a long one, we can split the hole series (break the fastener into two) as follows. First, if the Smart Fasteners property manager isn’t open already, open it by right clicking on the smart fastener icon in the feature manager and selecting Edit Feature from the menu. Once in the dialog box, expand Series 1, like in the image, to see all the hole features the Smart Fastener goes through.  Decide which hole features you want the new fastener to go through. In this case, we have four hole features and we want one fastener to go through the first two holes and the second one to go through the last two holes in the series. Drag the first hole feature for the new fastener (in this case, the third one in the series) and drop it on the fastener’s name at  the top level of the tree. By doing this, this hole feature and any other hole feature that comes after this one in the original series will now be part of a new series for the second Smart Fastener. The first two holes will remain in the original series. A message box will appear telling you that this operation will likely result in fasteners of different lengths. You have the option of choosing if you want to calculate new fastener lengths for both series or if you want to keep the original length for both of them.

Once the splitting operation is done, you now have two fasteners instead of one, each with its own hole series. If you don’t like the orientation of the fastener, you can always flip it, by right clicking on Series 1 and choosing Flip from the menu.

As a side note,  if the orientation of the parts in this assembly was slightly different, like in the following image, this whole procedure wouldn’t be necessary in order to have two fasteners instead of one. We could simply select two of the holes (see selection in the image) and two fasteners would be added.

So, there you have it. I hope it helped someone out there. And for all of you that may be reading this, if you have ever wished you could inspire others to pursue a career in engineering, mathematics, science and/or technology, please, consider becoming a mentor for women and others under-represented in these fields. Check out Mentor Net , if you wish, or simply go and take the time to share some of your knowledge and experience with others. You never know who you may inspire just by being yourself!

Dreaded Summer

The school year is soon coming to an end. For many, it means vacation time, long lazy days of fun and play, and perhaps a few trips to the beach. For most of my neighbors it also means finding alternative, and hopefully affordable, daycare options that  may work for them while school is out.  Due to the high cost of living in this area, most of my neighbors are two income families, both of them working for some company in the Silicon Valley. During most of the year, a combination of school and a few hours of childcare works really well.  For the Summer, however, you can see them making all kinds of arrangements for back to back day camps, summer classes, sports and activities, etc., that are not precisely childcare, certainly not as expensive as a nanny or a daycare center, but that will have to double as daycare, just so they can continue to work, and save a few dollars. Sometimes, I feel a mix of guilt and sadness when I realize that I’ll soon be joining “the club”.  Sometimes, I feel a bit envious of my next door neighbor. She works as a teacher and has vacation time whenever her kids are on vacation. Her schedule also allows her to be home when the kids come back from school, so the only times she ever needs childcare is when her children are sick.  I don’t think I would like to teach elementary school, like she does, but if I was to become a teacher someday, perhaps I would teach Science and Technology… Or,   I could even teach SolidWorks! What? One can have dreams, right?

Other friends and neighbors, male and female alike, have managed to negotiate a flexible schedule that allows them to work from home one or two days a week, or at least every other week.  Even one of my husband’s Marketing guys has recently asked him to allow him to do just that. He doesn’t have small kids at home, but he commutes from another city, and the price of gas is burning his budget. I often wonder how easy it is to find that kind of flexibility in a CAD job.  I don’t think it should be that hard, but  who knows, I may be wrong. I’ve researched a bit about flexible jobs for mothers,  and found that what’s available often serves candidates in non-engineering areas. I’ve found sites like MomCorps, for instance, that matches candidates with companies offering part-time, contract or full time flexible jobs.  But when I did a quick search,  there was nothing available for an engineer in this area. So, how much flexibility is there for an engineer mother of small children? How much flexibility is there in a CAD job? I guess that’s what I’m going to find out real soon.

Hole Series and series of questions

Perhaps the most frustrating and rewarding thing about being a self-learner is that you have to figure things out on your own, and, for the most part, it means that  you’re likely to find at least ten wrong ways to do something before you can find the right one. And then you have to figure out what was wrong about the other ten! The good part about this process is that (hopefully) you’ll learn something along the way, and won’t make the same mistakes again (now you’ll make new mistakes).

I’ve been going through the Advanced Assembly Modeling manual, learning about top-down assembly modeling and assembly features.  Talk about challenging!  Editing or creating parts in the context of an assembly isn’t really the complicated part, but keeping track of all those references is! So far, so good, but I’m still struggling with some of the assembly features. More in particular, I’m still struggling with the Hole Series.

An assembly feature is one that exists only in the assembly. It won’t propagate to the part level. This means that if you have your parts already placed and properly mated in your assembly and you extrude a cut through two or more of those parts, the cut will only exist in the assembly. If you open your parts separately, you won’t see the cut. This is true for all assembly features, with the exception of the Hole Series. The Hole Series is the only assembly feature that exists both in the assembly and part level. It creates hole features in each individual (unsuppressed and not hidden) component of the assembly that intersects the axis of the hole. The holes exist both in the assembly and in each individual part as externally referenced features (in-context). At first glance, the Hole Series is a very nice tool, because it allows you to set different hole sizes for the first and last part, and all the parts in between them that are affected by the Hole Series. It also gives you the option of applying matching smart fasteners to the holes automatically. For instance, consider this simple assembly of only two parts.  Preselect a face and click on Insert, Assembly Feature, Hole, Hole Series. This will open a dialog box and allow you to position your hole or holes in the graphics area.  Every time you click on the graphics area, you create a point that defines the position for a hole, so be careful where you click. You can first create as many holes as you need and position them later, by applying relations and dimensions, just like you’d do with any other sketch. This first step also gives you the option to automatically add a Smart Fastener, or to use an existing hole (one created with the Hole Wizard for instance) as a seed for the series.

Click Next to select your options for the first part affected by the hole series. This part looks pretty much like the Hole Wizard, but these options will apply only to the first part or component in the series.

The next dialog box allows you to select options for the size of the hole in the middle part(s). This little assembly doesn’t have any parts in the middle, so it’s OK to choose the option Auto size based on start hole.

The last dialog box is for selecting options for the hole in the last part. Same as the middle part, it can be custom sized or auto sized based on the start hole.  It can be a simple hole or a tapped hole, and it can go all the way through the part or have a different end condition (blind or up to surface).

I’ve found that the Hole Series feature works really well when used in assemblies where all the components have been created separately, with no external references to each other’s geometry. I don’t know. It may just be that I’m not really experienced with external references, but I suspect that, at least in some cases, it may create references that throw the system for a loop, trying to update a part that references another one, that itself references the first one. Does that make sense? I’m not sure why, but that seems to be what happened for one of the exercises at the end of the first chapter in the manual. I applied a couple of Hole Series, according to the instructions in the manual. Everything was OK after the first one,

but once I applied the second one, everything changed and now several parts in the assembly indicate the need for rebuilding. So, I update one part and another one needs rebuilding. Update the second part, and the first one displays the rebuild symbol again.

By the way, the file that contains the assembly in the last two images is available for download through SolidWorks. Simply go to the Customer Portal, and look for Training and Certification, there you’ll see a link to the SolidWorks Training Files that are available for download. These are just the files, no manuals.

Did you notice the rebuild icons in two of the parts in the assembly? I believe this issue is related to the references created by the Hole Series, because I later removed the second Hole Series and created the holes using the Hole Wizard. It worked perfectly, and no rebuild icons showed up. But of course, the holes will not propagate to the parts. Even when using the Hole Series with parts that have no external references, and because  the Hole Series will create externally referenced hole features in your parts/components, there are at least a couple of things to consider.   

First, you can’t use Hole Series with multiple instances of the same part or component. This one is fairly obvious. The part would be trying to add external references to itself. Doesn’t make sense! You can use Hole Wizard with multiple instances of the same part, however, because Hole Wizard won’t create any features outside of the assembly.

The second thing to consider is that the holes generated by the Hole Series can be edited, like any other feature, but only at the assembly level. In the part’s feature manager, it appears like a Hole Wizard feature, but if you try to right-click on it, you’ll see that you don’t have the option to edit the feature included in the menu.  If you open the part separately from the assembly and right click on the feature, the menu that displays gives you only the option to Edit in Context, which simply means that it will take you the assembly where the feature was created, so you can edit the feature at the assembly level.

I’m still wondering about that second Hole Series in the exercise and looking for answers. Could it be right to assume that the external references are the ones creating the trouble? What do you think?

Finally Caved In

Yeah, that’s right!  After trying so hard not to, resisting with all my might, and swearing I would never do it, I finally gave in and decided it was a good idea to become a member of the Society of Plastics Engineers after all. I have always been reluctant about joining this kind of societies. Many years ago, while still in college,  some of our teachers and advisors got us all fired up into joining ASME and IEEE (my major is actually known as Mechanical and Electrical Engineering in Mexico). As student members, the fees were very low and we received their magazine for free, but that’s all we really got from it. So, I discontinued my membership after graduation. A few times I thought about rejoining, but it didn’t seem like the benefits would outweigh the cost, just to receive a magazine that I could read online, anyway.  However, I think I’m beginning to change my mind about how useful it can be to be a member of a society of professionals, such as ASME or SPE. Why? Well, I’m not really a Plastics Engineer, just a Mechanical Engineer who is very curious and wants to learn about plastics, but after reading about what they have to offer to their members (many times free of charge), it appeared to me that it could be very beneficial, even for those like me that are just trying to get their feet wet and learn a bit.

In addition to the proverbial magazine that all societies seem to offer, and the member discounts on materials (some of them only available through SPE), training and continuing education, seminars, webinars and other events, what really got me excited was the free access to their online technical library, their interactive plastics encyclopedia (coming soon), their topic specific newsletters, consultant circle, networking opportunities with other members, locally and internationally, as well as other personal benefits, such as scholarships, and tools for career development and job search. So, for only $125, I think I can afford to try it for a year and see if I like it or not.

I know what you’re thinking. You are probably wondering what does this have to do with SolidWorks. Well,  nothing really, except that  with all the recent talk about improving and revamping the SolidWorks online community,  I couldn’t help but imagine that similar benefits could be offered to SolidWorks users, and to have all of this available  together under one roof. Imagine that! In fact, many of these same benefits are already offered (forums, knowledge base, newsletter, a collection of past presentations, user groups, technical summits, etc.), but I’m not exactly sure if they are at all accessible to those that are not service subscribers, like students and others (I don’t have access to many of those areas myself), or if they are easy to find and use as they are right now.  I know that community is built in many different ways and that it happens on its own wherever two or more users gather together, but at the same time, I do look forward to that extreme makeover that SolidWorks is planning on, especially if it involves making more (free) information available for the users, all users, making quality training more affordable for everyone, and providing more opportunities for career development. Hmmm, you never know. It may happen.

Flexes, Hexes and Vexes

As the week begins, I feel proud to say that I’ve finally completed one more of the SW training manuals, the Advanced Parts Modeling one. Each day, I’m getting closer and closer to finally feeling prepared enough to try my luck with the CSWP test, but most importantly, I’m learning  tons of new stuff about SolidWorks, getting some practice, and having lots of fun along the way.

Among the exercises in the very last chapter of the manual, there was one that I struggled with for quite a while. The part was a model of a box, probably made out of Styrofoam or plastic, like the ones they provide at restaurants for you to carry leftovers or take out.  The box had a living hinge and the exercise consisted of applying the Flex command to bend the box into a closed position. I tried following the instructions in the manual, with exactly the same numbers and conditions, but my Flex feature kept failing. Frustrated, I decided to  check out the built part, the file that is included as a solution for this exercise, to see how the Flex feature was done there and make sure I wasn’t  making any mistakes.  Well,  I opened the part, edited the Flex feature, and couldn’t find anything different from what I had been doing so far, so I clicked OK and then it happened:  the Flex feature failed for the solution part,  as well! How come? It worked fine when I first opened the file!  It had to work for whoever modeled that part. How did they make it work in the first place? I reloaded the file and it seemed fine again, but then it occurred to me to force a rebuild by pressing Ctrl+ Q, and, just as I thought, the Flex feature failed once more. It was then that I remembered I had the option “verification on rebuild” turned on.

Verification on Rebuild is an option that controls the level of error checking when you create or modify features. By default, without using this option, every time you add or modify a feature, SolidWorks will check it against any adjacent edges or faces. With the option turned on, the features will be checked against all faces and edges. If a feature causes any invalid faces or edges, it will fail when this option is turned on.

I cleared the option and rebuilt the model. The Flex feature was successful this time and the model looked OK, but when I checked the model geometry (Tools, Check), it turned out the Flex feature had created three invalid faces.  That’s why it failed when the option was turned on! I wondered for a long time what this could mean for the model. Did it mean that the design needed to be modified? That a box manufactured based on this model wouldn’t work properly?  I asked Matt Lombard about it, since he’s got plenty more experience than I do, and he had mentioned before that he wrote part of this manual. He told me Flex  features are a bit flaky and can easily create problems like that one,  that is better not to use them with real geometry, but only for “looks like” stuff, like when you want to illustrate how a part would look like in a different position. I think I’m  beginning to understand why.

As an exercise for myself, I modeled  a small plastic bottle cap. This bottle cap is attached to a ring that goes around the neck of the bottle, to help keep track of the bottle cap.

Just as it was done in the manual, I applied the  Flex  command to bend it into a “closed” position, to simulate how it would look like.  So, I clicked Flex, from the Features toolbar and got the Flex command  dialog box and, in the graphics area, a couple of trim planes and a triad. The triad is a coordinate system that that sets the center of the flex and the orientation of the trim planes. The bending takes place about the Bend Axis (the red axis in the image) and in between the Trim Planes. The Trim Planes are usually created at the extents of the part, but can be moved to a different location. The triad and trim planes  would assist me in the process of bending the part, but first I needed to reposition them. For this purpose, I had created a centerline sketch, right in the middle of the part. Repositioning the triad can be done through the dialog box or by right clicking in its center and choosing to either move it  or align it with selected geometry in the part.  I moved the triad so it would be located right in between the ring and the cap, and also so that the Bend Axis would be aligned with my centerline sketch. I also repositioned the Trim Planes using the dialog box to select a couple of vertices in the part to reference them.

Here is the way it looks like from the front.

Once I had that figured out, the next step was to enter the angle for bending. Notice how it bends about the red  Bending Axis.

And this is the result. The lid in a closed position. The angle here is 180°.

Now, while creating this part, I had the “Verification on Rebuild” option cleared out. So, I decided to check the model geometry for any invalid faces and edges and , yes, there were three invalid faces that were created right after using the Flex feature.

After playing with the options for a bit, I noticed that the problem disappeared if I suppressed the fillets, so I reordered the features in the part and placed the second set of fillets right after the flex feature. Then,  I checked the model geometry again (Tools, Check). This time, there were no invalid or even inconsistent faces or edges in the model geometry.

So, one more reason to leave fillets for the very end? Well, yes, it would seem like it, but for me is more a reason to be careful when using the Flex feature, and to follow Matt’s advice, and use it for “looks like” stuff, rather than design.  I’m still curious to know what could keep the Flex feature in the box from failing. Matt promised to take a look at it as soon as he has some time. I’ll be waiting!

Random Thoughts

OK, if this sounds too odd or corny, then I’ll blame it on the flu, even though this morning my temperature has finally come back to normal.  Right after posting about the SolidWorks Community Survey,  I went to fill it out myself.  I must admit that I was expecting something a little bit different. It didn’t even take me ten minutes to finish it. I was expecting it to be a lot more thorough, but I’m keeping my hopes up high for the follow up survey in a couple of weeks. Then, reading Matt Lombard’s blog and the SolidWorks forum, I realized this survey is already creating a bit of a controversy among the users.   I think I have to agree with what someone in the forums said that the survey mainly seemed to be trying to find out if people would like the idea of merging the different sub-communities and forums into one big thing. I’m curious about what  SolidWorks actually has in mind. Who knows? It may be something grand. I wish they let us know what their idea is all about. I also agree that, in any survey, it’s nice to see what the results look like so far, as well as what is going to happen next, based on those results. I think Matt calls that “transparency”.   What I didn’t see in this first survey  was room for suggestions that were not contemplated in any of the questions, kind of like the wish list Matt refers to. However, it is encouraging to see that SolidWorks is actually listening to the users, not only through this survey, but through the forums and comments they leave in the blogs.  It also seems awesome to me that the simple act of coming up with such a survey can stir up the community of users to share their ideas and thoughts BEYOND the survey, like they are doing it now at the forums.

Community.  What a powerful word it is. Just stop and think about it for a moment. I have to tell you that finding and being part of this kind of community is a first one for me.  Pretty much like my experience with solid modeling, I had never tasted anything like it.  I warned you, it was going to sound a bit corny, and you may not agree with me, but it’s the way I feel it. If last year you had asked me “What is SolidWorks?”, I would’ve said something like, “Oh, SolidWorks is just one of the CAD software programs that I intend to learn and add to my list in a resume, right there with AutoCAD, Inventor, Pro/Engineer and any other that I find along the way and may consider useful.”.   Today, my answer would be a very different one.  I’m not saying that it’s not a good idea to learn to use other software.  I still have AutoCAD, that I rarely use these days, but I still know how to. I have also tried other CAD that was offered as demos and watered down freebies, as well as educational versions. And you know what? I keep coming back to SolidWorks!

Time and time again, I find myself preferring SolidWorks over any of the other ones. Why is that? I don’t know, but I think that SolidWorks has become something more than just a CAD software to me. Of course, I love all the functionality it has to offer, and how powerful it is, and how easy it is to create with SolidWorks all sorts of things that I never even dreamed possible. But it’s also the community. SolidWorks is not just a software because it is also the people and the world that revolves around it: the users, the experts,  the network, the user groups, the special events and meetings, the forums, the mailing lists, the blogs, the different websites that offer tips and tricks, the people that work for SolidWorks and that is constantly in touch with the user. This is all SolidWorks! This big community that keeps spinning, transforming and becoming stronger day by day.  Even those that have nothing better to do than criticize the software and the people who use it left and right are helping it become stronger! They don’t realize that whatever comments they mean for evil, will only help SolidWorks pinpoint possible problems and solve them. After all, if all the feedback you provide is saying that everything is always perfect, then you are not giving SolidWorks a reason to improve. So, to all those guys goes a big “thank you”.

Anyway, I told you that you may not agree with me on this one. This is what SolidWorks and community mean to me. You may call me a SolidWorks fan, well you’ll be darn right. I am a big SolidWorks fan, so what? You may have a different idea, and it’s OK too. Oh, look! I think I am running a fever, after all.

Building Community Together

Hey folks, here’s your chance to make your voice heard and tell SolidWorks what community means to you,  what you like, don’t like, need or want from the SolidWorks Community! SolidWorks Corporation is conducting a comprehensive survey that will help them find out all that, but they need our cooperation. How can we help? Well, simply by filling out the survey, of course. This is an awesome opportunity for all of us involved with SolidWorks, because our answers will help them  provide a better service in areas like training, networking, model sharing,  among others.  The survey takes 10 minutes to complete. So, what do you say? Will you do something to improve your SolidWorks  Community today? We will all benefit! So, what are you waiting for? Go and complete the survey today!

It's the way we connect

I don’t know what tops your list of favorite activities, but for me nothing beats  “Date Night”  with my hubby.  Whenever we have a chance, we leave the kids with a babysitter and head over to the most romantic place in town. Why, the bowling alley, of course! OK, so it’s not precisely what the dictionary describes as romantic, but we always have a great time there, and part of the fun comes from watching other people bowling.  Everyone has their own style. From the fragile-looking little girl, who barely holds the ball with her fingertips and gently places it on the lane, yet manages to knock down every single pin 90% of the time,  to the tough-looking, 6’4” and nearly 300 lbs guy, who seems to cradle the ball in his arm as he approaches the lane, then sends it flying  in the air, so it will land half-way down the lane, follow a curved path, and knock down all the pins, also at least 90% of the time. It’s a good approach! I tried it myself and made a strike. Unfortunately for me, I scored it in the neighbor’s lane. Anyway, at least in recreational bowling, the way you make it from A to B doesn’t seem to make much of a difference (although it is somehow important when buying yourself a bowling ball), but it does matter when in solid modeling, particularly, when you’re working with lofts.

One thing I’m learning is to be mindful not only of the way you pick your profiles for lofting, but also the way you prepare such profiles for the operation. Lofting allows the user to create a solid, surface or cut that is defined by several cross-sectional profiles, by interpolating  geometry  between  said profiles. This allows us to create smooth transitions between very different profiles.  However, the way you pick those profiles has a lot to do with how smooth that transition actually turns out to be, and, in fact, if you aren’t  careful, you can end up with unwanted twists, ripples, or even a loft that will fail altogether. If you ask for advice, people usually tell you that what you need to do is pick corresponding points on each profile. Hmmm, well, that would be easy if you were lofting a couple of squares, but what if one of your profiles is a closed semi-circle and the other one is a rectangle? Well, there’s also that other piece of advice that you don’t hear very often but that comes in handy for this kind of situation: each profile should have the same number of segments.

What does it mean for the profiles  to have the same number of segments? Well, if you look carefully you’ll notice that when you pick your sketches, edges or surfaces for lofting, SW generates  connectors that show you which vertices will be connected with each other during the loft.  If for example, one of your sketches is a square, it will have 4 vertices, that will have to connect in, at least  four different points with the other profiles in your loft. If your other profile is a circle, the system will divide it in four different segments, so it can create the connectors as needed. This may or may not give you the results you expect. You have better chances of succeeding if you divide your profile in segments yourself, so that the number of segments is not only the same in all profiles, but the location of the points where the profiles would connect with each other also corresponds to your expectations. In the following image, a closed semi-circle(2 segments) is lofted to a heptagon (seven segments), without any previous preparation.  SW has divided the semicircle in segments and created connectors between both profiles. Notice how the loft  is twisted, even though I tried to pick the profiles in points that seem to correspond to each other. By the way, if you can’t see all the connectors in the preview of your loft, simply right click on the graphics area and select Show All Connectors from the menu.

You can change the location of the connectors by picking and dragging them  (by the blue dots) in the graphics window. You can even add extra connectors as needed. The  number of connectors and their location is going to affect the transition between the profiles in the loft, as you can appreciate in the following image, where some connectors have been moved and others added, kind of willy-nilly,  merely to illustrate this fact.

As I said before, you can also prepare your profiles for lofting, by dividing them in equal segments yourself, according to your design intent. In order to do that you can use Split Entities, from the Sketch Tools. Simply select the entity you want to split or divide in segments. A split point will appear on the entity, near the location where you selected it. Use relations or dimensions to correctly position the split point where you want it to be.  Notice the difference between the following loft from a square (4 segments) to an octagon (8 segments). In this one, the system divides the profile in segments.

In this other one, I divided the square in segments myself, placing split points in the middle of each side. Looks better, doesn’t it?

There are other ways to affect the transition between the profiles in a loft, like the use of end constraints, centerlines, and guide lines, but I’ll have to tell you about those some other time, because I’m still working my way through them. Now it’s getting really interesting! I think I’ll never tire of exploring what else can be done in SolidWorks! Definitely nothing to do with what I used to draw in AutoCAD years ago!

Bummer!

It may just be that I’m running a fever as I write this, I’ve been as sick as a dog all this week, but I can’t help feeling this way.  Can I pour my heart out to a listening ear out there on this vast cyber universe?  Well, it’s like this. My own copy of the newest SolidWorks book I had been (un) patiently waiting for so long finally got here just a few days ago. It is, indeed, a great book, great quality, lots of colorful illustrations, plenty of examples and lengthy explanations, and written by a famous bestselling author. Who could ask for more, right? Well, it is really great, only I have a bit of a problem. You see, I’m using an educational version of SolidWorks 2007, and all the files and examples contained in the book were created in SolidWorks 2008. Why is this a problem for me? Well, simply because  there is no way I will ever be able to open  the files  in SolidWorks 2007, there’s no way to convert the SW2008 files into something I can open and still benefit from (parasolid won’t do for the purposes of the tutorials in the book), and at least for now, this is the only SolidWorks I can have. Bummer!

I’m not complaining, really, I’m not. Well, OK, maybe just a bit. But I’m not complaining about the book, because when I ordered it, I already knew what I was getting into. It didn’t take me by surprise. I knew the examples were modeled in SW2008, and that I would not be able to open them, but I bought the book just the same, because I also knew how hard it is to get reliable information on this particular area of SolidWorks and I just wanted to learn. I tried really hard to win the SW2007 training manuals for this particular topic on eBay, but it’s a task that proved to be impossible for me, someone always snatched out of my hands 10 seconds before the end, so I went for the book instead.   Hmmm, I wonder if you know what book I’m talking about. Chances are you own one too!  Did you guess?  Yes, of course you know!  It’s Matt Lombard’s  new Surfacing and Complex Shape Modeling Bible. Really nice book! It’s a soft cover, but it has the quality, looks and feel of a hard cover book.  I hope I can still get a lot out of it, even when I’m not able to open the files and examples. I have been browsing through it and it looks like I may as well be able to.

Like I said, I’m not complaining, but I do feel  bummed out about this reality of what using an older version of SolidWorks means. It means not being able to open files and share documents with users of the new version. It means not being able to fully benefit from books like Lombard’s, because they mainly target the new version. It feels like missing out on a lot of good stuff and not getting the materials you need to learn, unless you can pay thousands to attend the special training at the VAR or you are lucky enough to win a manual on eBay. I feel like I’m on the outside looking in. And  in many ways, I guess I really am,  especially since I’m only using an educational version of the software, that will expire in a year and months, and after that, well… I really don’t know.  I wish I could buy my own license of SolidWorks, and I’m saving some money, but for now it’s only a dream. SolidWorks is not cheap, and, as Vic Leventhal said to us during that first Tri Valley SWUG meeting, it’s not likely to ever become cheap. So… It is more likely that in a year or so  you may find me working for a company in the area and who knows what version of SolidWorks they’ll use, or if they’ll use SolidWorks at all. I hope they do, because I love the software and I’m putting a lot of effort into learning how to use it. In the meantime, all I can do is make the best of what I have and the resources available, and keep at it, even on those days when it feels that I’m merely muddling through it. Even though I’m on the outside looking in, I’m still grateful for that little window that was left open for me to gaze into all this marvelous world that revolves around SolidWorks and that, otherwise, I would’ve never known it existed at all. Maybe someday I’ll manage to get in, who knows? You got to have a few dreams, right?