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Posts Tagged ‘Surfaces’

Bloggers don’t blog?  Sorry guys!  I was dealing with quite a few health issues and going through a lot of antibiotics as part of a trial and error strategycareful scientific methodology and thoughtful planning devised my doctor, and all because I’m allergic to Penicillin. But I’m finally feeling better and back with some goodies that, I hope, many of you will find useful.

First of all, let me tell you about the SWUGN San Jose Technical Summit that took place just yesterday, March 23rd, in the city of Milpitas, CA.  As I mentioned before in a previous post, I was there to present about Easy Surfacing Techniques for Solid Models. I was extremely nervous because this was actually my first time presenting for the SolidWorks community… well, OK,  my first time presenting anything for anybody since my last year of college, back in 1996. Yes, I know… 1996… I’m old.  So what?

I was fortunate to find quite a few familiar faces at the event: Richard Doyle,  Alex Ruiz (SWGeek), Matt Lorono (fcsuper and SolidWorks Legion), Phil Sluder, Brian Titus, Kenneth Barrentine, Elise Moss, and a few other people that I’m absolutely sure I’ve seen at SolidWorks World before.  Richard, Alex, Matt and Elise were presenting too, but I couldn’t stay and attend their presentations because I had to run back home to be with my younger son and allow my husband to go back to work. See, my husband selflessly sacrificed his morning to allow me to be at the summit long enough to present, but I couldn’t ask him to sacrifice his whole work day.

Anyway, at least, the time I was there was lived to the max. Despite the butterflies in my stomach, my presentation went a lot better than I had expected. In fact, quite a few people told me that  it actually went great!  And all those things I had worried for days (finishing too soon, making lots of mistakes, presenting for an empty room,  forgetting everything, having an accident in the freeway, wearing my clothes inside out) never actually came true.  This may seem silly to some, but it was a great victory for me. As I left the building, I felt so happy I was practically doing the jig on the way to my car. I just hope nobody saw me.

And now to the goodies. Because I promised it to the people in attendance, I have prepared a pdf document with step by step tutorials of each and every single one of the eight examples I showed yesterday at the summit. It’s 38 pages long and loaded with illustrations. I’m making that available here, together with all the parts and assemblies used in the examples, plus the solved examples to compare.  To download them, just follow the links.

Easy Surfacing Techniques for Solid Models

Example files

Example files (Solved)

I’m thinking I may as well start a new page to list downloads. Writing those tutorials was a fun experience, since I was able to include more detail than I usually do in a blog post, so I may be creating and adding more of those in the future.

The first training session I attended was presented by Charles Culp, who is very well known at the SolidWorks Forums.  Charles was introducing all of us to a series of useful surfacing techniques, including how to convert a solid body into a surface body, fix some geometry, and then turn it back into a solid, the proper use of Delete Face and Delete Hole, the advantages of using Replace Face, and the difference between a boundary surface and a filled surface.  I arrived a bit late, but still managed to see him fixing a funny looking fillet located in a corner, similar to the one circled in red in this image. I tried really hard to reproduce what he had, but mine doesn’t quite look the same.

Anyway, he showed us how to trim and delete faces from the fillet, and then use Fill Surface with tangent option to patch the hole with a new, smooth surface, just like you see here in this image.

Of course, like I said before, my example isn’t exactly like his, so I did a few things differently to be able to delete the right faces, but the method and result are pretty much the same.

He also demonstrated how to model a telephone cord, by first creating a helix that follows a 3D spline. This is what he did: He started by opening a 3D Sketch and creating a 3D spline on it. Next,  he created the sketch of a line on the plane normal to the 3D spline at one of its ends and used it to create a Swept Surface, using the option to twist along path, as you can see in this image. The result is a helical surface that follows the path of the 3D spline.

He opened a new 3D sketch and selected the edge of the helical surface, then used Convert Entities to create a sketch of a helix.

Then he created a reference plane normal to one of the ends of that helix and sketched the cross section of the cord.

Finally, he created the telephone cord using the Swept Boss feature, with the sketch of the cross section as a profile and the helix as path. No need to twist this time around.

I wish this had been  a hands-on session, if only to have a copy of the original examples Charles used for his presentation. It’s OK; even though it wasn’t a hands-on session,  it was full of useful  information just the same. I believe the procedures of this and other sessions will be available in March. Until then, all I have to offer is my condensed version.

Stick around.  More chronicles from SWW2010 are  on their way!

The weekend seemed very short and I apologize for not putting this up earlier, like I said I would, but I wanted to spend time with my husband, who had just come back from a long trip to Japan, and celebrate both our birthdays while he was here for a couple of days before he had to go back to Japan for a trade show.  Every year is the same: he’s travelling during the week of his birthday, by the end of September, and again during mine, the first week of October. It never fails! But I don’t complain, because God has blessed our family by giving him a great job, and that’s plenty.

Anyway…  Transforming the plain round head of the funkey into a mouse’s head began by changing the sketch for the revolved surface from an arc (spherical head) to a partial ellipse (oval shaped head).  I also changed the axis of revolution, just tilted it up a bit.

Next step was to modify the ears. Instead of revolving the sketch 360 degrees as before, I only revolved it 180 degrees and then thickened the surface to a solid, by using the command Thicken, then mirrored the ear with respect to the Front plane and filleted the edges.

On the Top plane I made a sketch to aid me in the process of shaping the mouse’s snout. I used the sketch to trim the face’s surface with it. In the image, you can see the surface I’m removing in purple and the sketch appears in blue on the Top plane. Notice that there is a projection of this sketch on the back of the head, but I didn’t select that surface to be removed as well.

After trimming the surface, I patched the hole with a new surface using Fill Surface.  I didn’t really want to just patch the hole; I wanted this surface to have a more pronounced shape, different to that of the face. My goal was to create the nose of the mouse, so I thought if I added a point as a constraint curve (the one you see in the image), the new surface would have to pass by that point and I’d be able to shape it that way into a mouse’s snout. Well, the idea was good in part, but you can’t really depart that much from the original shape by using this method, or else the Fill Surface will fail. This is as far as I was able to locate that point.  I get a bump in the surface, but not so much for a mouse’s nose.

And this is where I decided to try my luck with the Freeform tool.  By the way, before you read any further, I would like you to take a look at a very nice video that Mark Biasotti shared with all the community through the SolidWorks Discussion Forums. You can find the video at: http://files.solidworks.com/special-videos/freeform demo.zip  This video explains in more detail how to use the Freeform tool.

Did you check out the video? Great! Now I’ll tell you how I used Freeform with my mouse.  First of all, I established that the boundary conditions at the edges would be Contact. Why? Well, because I wanted to deform that surface considerably and I knew the result would certainly not be tangent or have the same curvature of the face, but that was OK with me. For your own projects, however, you may want to keep the edges tangent or have the same curvature, so keep an eye on that.  I also established that the deformation would be symmetrical with respect to the Front plane by choosing Direction 1 Symmetry. What this means is that whatever I do to one side of the surface will automatically be done to the other side, thus making my work easier.  Notice the plane of symmetry in the middle of the nose. In this particular case, the plane is coincident with the Front plane of the model.

Next, I added a few curves (they appear in green in the image) by clicking on Add Curves and placing them pretty much wherever I thought I needed them.  On most of these curves, I also placed a few points, by clicking on Add Points and placing them over the curves I had just added previously. Each one of these points would allow me to push and pull from it, thus deforming the surface. Pulling a point in one of these curves will affect the appearance of the rest of the surface, at least up to the next curve. It sounds complicated, but each one of the points also has a Triad that gives you some control over the whole deformation process. You can either pull directly on the screen or enter numerical values for each axis direction in the property manager.

While you are at it, if you take a closer look at the edges of the surface being deformed, you’ll notice some arrows/vectors. If you click on them, a Triad will show up and by manipulating this Triad you’ll be able to adjust the tangency and vector direction of the surface right at the edges.  This will also affect the look of the rest of the surface.

So, basically, this is what I did with Freeform. I spent a few minutes pushing and pulling, adding and removing points. Just dynamically changing the surface until it looked the way I wanted it. I wasn’t really worried about creating the best of surfaces at this point, or if the mouse would be able to be manufactured or not; I just wanted the looks. Nevertheless, with some effort and perhaps a sketch or two to guide the deformation, I believe better results can be achieved with this tool.

Moving on with the rest of the mouth. Before deforming the surface, I had made an offset copy of it to serve as the back of the mouse’s mouth, by using the Offset Surface tool, as you see here.

Then, once the surface had been deformed, I trimmed it again using another sketch I made, again on the Top plane. This sketch will help me shape the smiling mouth. You can see the sketch in blue and the purple area is the surface to keep.

Once I had the gap for the mouth, I opened a 3D sketch and placed a two-point spline from corner to corner, like you see here.

I used this 3D sketch to create a couple of surfaces using Fill Surface. This is one of them.

And this is the other one.

Notice that the surfaces intersect the one for the back of the mouth that was previously created using Offset surface.  It’s time for some trimming.

First, I trimmed both new surfaces against the one I had created for the back of the mouth. In the image you see the parts in purple are the areas to keep and the surface in black is the one for the back of the mouth, used as the trimming tool.

I trimmed the back of mouth surface against the other two in a very similar way and then knitted all three surfaces together.

The eyes were made in a very similar way to the mouth. First, using a sketch to trim part of the surface of the face…  The sketch appears in blue and the area in purple is the one being removed.

I then opened a 3D sketch, converted the edge of the snout, thus creating a spline, and trimmed the spline  to the edges of the eye hole, like you see here. This sketch will be used to loft a surface for the eye.

This is the loft for the eye. As you see here, the lofted surface was created between the edge of the eye hole and the 3D sketch. I added a start constraint using the Top plane to define Direction Vector. I just wanted to give the eye some volume and make it look like it was popping out of the face.

The rest of the features for the face are fairly simple. The black little nose was made using a surface revolve and the teeth are just a couple of extrusions.

I’m still fascinated by the Freeform tool, however. I want to explore it further and see what else it can do and what other applications it can have, but most importantly, learn to control it a lot better than this in order to achieve the best results possible.

Hey! It’s been quite some time since I updated this blog. I’ve been engrossed in a refresher of Chemistry and Materials Science, in hopes of better understanding about manufacturing processes of plastic products. Back in the day, I used to love Chemistry, and I think I wasn’t so bad at it, although some people may disagree with me, all because of a one-time tiny accident that left the lab stinking like rotten eggs for a couple of months. Anyway…  Today or tomorrow I’ll write about this model you see here, which is a modification of my original funkey. The inspiration came from a brief conversation with my brother. He’s an architecture student in Mexico, and he was telling me about how our sister, a graphics designer, had requested his help in creating the 3D model of a mouse to include in some sort of advertisement. He showed me samples of the renderings he had made, and that was enough to get me going. I had to have my own mouse!

I didn’t really spend much time in modifying this model; I didn’t have more than a couple of hours to spare.  So, basically I reshaped the head (partial ellipse instead of an arc), made a few trims, lofts, and filled surfaces here and there, and most importantly, shaped the snout using Freeform command.  I’ll explain all that in more detail in my next post.

Now, I’m not sure this mouse could even be manufactured as it is. I just wanted the looks, and it was also a good exercise in the use of the Freeform command. I used to feel much intimated by it, but I’m finding that it’s not really that hard, and the best of all is that I can go back and edit the Freeform anytime I want. Perhaps with a bit more practice I will be able to model really neat stuff.  I didn’t have a layout of some kind to guide myself in shaping the snout, so I just pulled and pushed until it looked good to me. I know it could look much better than that…

Now, please, somebody tell me this does look like a mouse!  I was never the artistic or creative one of the family, you know?

Tell you more soon!

I must confess that the arms were quite a challenge for me.  My result is not perfect, I know, but I think it’s close enough.  Not so bad for a beginner, at least? Anyway, I had tried doing a surface sweep, but it didn’t look good, so I went with more lofts.  I started by creating some more geometry (What a surprise!).  I sketched a spline on the Top plane, following the silhouette of the arm when seen from above (assuming the funkey is lying on its back).

I used that spline and the sketch of the parting line I had made for the body to create a parting line for the arm as a projected line of the two.

Next, I created a couple of sketches on the Front plane to help shape the lower and upper half of the arm when seen from the side.  Here’s the sketch for the lower half of the arm. It’s a spline sketched on the Front plane. Its endpoints are coincident to endpoints of a 3D sketch that is a copy of the parting line for the arm that was  just created previously. To make that copy simply open a 3D sketch, select the projected curve that is the parting line for the arm and use Convert Entities.  The spline is also tangent to a couple of construction lines which are perpendicular to the sketch of the parting line for the body, as you can see in this image.

My next step was to create three planes parallel to the Right plane where I would sketch cross sections of the lower half of the arm, as you can see here. These cross sections will be used as guide curves for a lofted surface, just like with the foot.

Each of these cross sections is a two point spline. There’s a piercing relation between one endpoint of the spline and the sketch of the lower half of the arm that was created previously and another piercing relation between the other endpoint of the spline and the 3D sketch that is a copy of the arm’s parting line. The spline is also made tangent to those two construction lines you see there, one vertical and one horizontal.

After I had my cross sections ready, I created a surface loft, using the sketch of the lower half of the arm and the 3D Sketch that is a copy of the arm’s parting line as profiles, and the cross sections I just created as guide curves.

The upper half of the arm was also modeled in a very similar way, with a surface loft between an upper half arm sketch and the arm’s parting line, only in this case I didn’t use any guide curves. I realized that for the kind of surface I wanted to create, the results were the same if I simply adjusted the start/end constraints to be Normal to Surface for the upper half sketch (with the end tangent length adjusted to 0.17) and Direction Vector for the parting line (with end tangent length adjusted to 0.54). The direction vector, by the way, was defined by one of the construction lines in one of the cross sections I sketched for the lower half loft. According to the Help document, Start and End Constraint applies a constraint to control tangency to the start and end profiles. Normal to Profile applies a tangency constraint normal to the start or end profile, while Direction Vector applies a tangency constraint based on a selected entity used as a direction vector. The tangent length controls the amount of influence on the loft. The effect of tangent length is limited up to the next section.

 

At this point, the arm looked pretty much like a fin. I trimmed the upper and lower halves using the rest of the body as the trimming tool. The purple area is the part of the surface that will be kept.

To finish shaping the arm from a fin to something more funkey-like, I created a third surface loft.  I started off with more auxiliary geometry. First, I created three planes parallel to the Front plane where I would sketch profiles for the loft (shown in purple). Two of these profiles are splines with a piercing relation to a 3D sketch copy of the arm’s parting curve (shown in yellow), and the third one of them is a point coincident with that 3D sketch copy of the arm’s parting line.

Next, I created a lofted surface using those three profiles and the 3D sketch copy of the parting line as a guide curve.

Then I trimmed this surface using the upper half of the “fin” as a trimming tool. The purple area is the part of the surface that was kept.

I trimmed the new surface and the upper half of the “fin” using a sketch as the trimming tool, as you see in the image. The idea was to remove a section from both surfaces and create a new surface that will blend them together (more or less) nicely at the elbow. The purple areas, as usual, are the ones being kept.

To blend both surfaces at the elbow, I decided to use a surface loft. I tried the Filled Surface first, but I didn’t get nice results.  So, I created a 3D sketch and converted the right edge of the hole in the “fin”  to use it as one of the profiles for the surface loft. Then, I made the surface loft, using the 3D sketch I just created and the edge of the other surface as profiles, and a copy of the arm’s parting line as the guide curve. Notice that the Start and End constraints for both profiles as Tangent to Face. This setting was the one that produced the smoothest results, without puckering at the corner where both profiles meet.

The next step was to take care of the funkey’s “hand”. First, I opened a sketch in the same plane where I had sketched the biggest cross section for this surface loft, converted the edge of the surface as you see in the image and joined the ends with a line to form a closed boundary for a planar surface.

Then used Planar Surface command with the sketch I just created.

I trimmed this planar surface using the body as the trimming tool. Again, the purple area is the one that’s kept.

 

Next, I trimmed the planar surface again, this time using the fin as the trimming tool. The purple area is the one that is being kept. In this case, you don’t see the portion of surface that is discarded because it’s extremely small, but enough to make other features such as Knit fail.

Now I trimmed the upper half of the “fin” using the lofted surface as a trimming tool. In this case, the area in purple is the one being discarded.

At this point, I discovered a tiny hole right in the corner where the surfaces meet that needed to be filled; otherwise it would prevent the knit surface feature from working. I used Fill Surface to patch it.

After patching the hole, I knitted all the arm surfaces together, including the tiny patch, and trimmed them using the body of the funkey as trimming tool. The area in purple is the one that is kept.

Then I mirrored the arm with respect to the Front plane. And then I trimmed the funkey’s body using the arms as trimming tools. This had to be done in two separate trims; one for each arm. Then simply knitted all three surfaces together: the two arms and the rest of the body.

I filleted the edges of the “hands” using a variable radius fillet. Notice the different values for the fillet at each one of the control points.

After patching the bottom of the funkey and the neck with a couple of planar surfaces, all that was left to do was to make the head, but that was easy, all I had to do was revolve three arcs and then trim the surfaces with respect to each other.

Wow! That was some long post! I didn’t think there would be so much to say about this model, and I simplified a lot to avoid making it way too long. If anyone needs the model, I’ll be glad to share it, of course. I apologize with those of you who are experts at surfacing if my model is too amateurish for you, but as I said before, I’m just getting started.

I think I like surfacing…