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darad

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About darad

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  1. For some reason, even with BAR filter, the selection of individual elements did not always work. Sometimes. And did not work for drag-box selection ever. Must be a screen graphic issue.
  2. Can Altair respond to why BAR elements cannot be graphically drag-box selected to define a SET? And add to Bulk Data. Then the user only needs Case Control: ELFORCE(OPT)=[set-id] Please add to the set of entites to define a SET, Simlab 2020 is not too late. More useful that defining RBE2's to a SET.
  3. Output of BAR element label is working somewhat now. Just not always responsive, whether single click or double click. Sometimes better hover time over the bar. An option for 2 or 3 pixel wide Bar display would be helpful for selectivity, and eyes to see visual feedback. Should one be able to drag box select a group of Bar elements via the bar filter? This does not appear to work. With 2019.3, BAR elements still cannot be defined for SETS. It would be nice drag-select a dozen or more BARS to define a set for ELFORCE(OPTI)=[setid]. Or, even by selecting a Merged set of Bar bodies into one body in Model Browser. Currently one cannot select any Bar element for SET definition. I'd rather be able to define SETS with bars, than with RBE's
  4. In a prior post, using Assembly, Boolean, Merge to connect bodies was illustrated, and 2D meshed as a single body. Then, Unmerge to separate the bodies again, and solid mesh each body while maintaining connectivity for FEA. With Simlab continuing to enhance Geometry modeling capabilities, I've attached a Powerpoint demo on how solid fillet welds might be created with ease and grace ... and just a few steps. Merge and Unmerge is also demonstrated. To achieve full potential with imported CAD, Save Geom in Database, a great enhancement would be a sketch pad. That is, being able to "sketch-in-place" and extrude on existing bodies (not a blank sketch pad) to create new Weld bodies or other structural shapes. We also get many assemblies, with edges prepped for welds, but without welds. Designers would rather not construct such features for the FEA engineers. These need be filled in with solid welds where needed, for the groove weld prep areas simply smoothed over i.e. boolean connect the bodies, and fill-in the grooves (actual weld body is not needed). This can be a real chore, if not impossible, in CAE tools without good solid modeling capability. Sorely needed enhancement. Can this be done? Maybe we could do this during the Lockdown! Solid Weld Creation Made Easy.pptx
  5. What I would really like is ability to Create CAD Welds, i.e. fillet, groove, fill-in weld prepped parts with welds. The current weld via modifying mesh doesn't work for me. Seems Simlab would need a Sketch-i-Pace feature to create precise weld profiles, and ability to extrude (vs polygon from existing vertices). The only tools that works for me is old NX I-DEAS 6.1, via its Master Modeler for reconstructing often bad STEP geometry from scratch, glossing over weld preps of zero interest, and creating all sorts of solid welded to evaluate stress. And leveraging its History Tree for creating bodies in a modular fashion, and integrating such features into the Tree. Easy to modify and update features via the Tree. Its Join Partition feature is/was so powerful -- like no other tool, not even newest SimCenter 3D. Join Partition allows Extruding a new part feature up to and beyond one or more faces. The resulting volume stops at those faces. Really superb feature. Else, one would need to create such weld volume face-by-face. Hence, until I-DEAS stops working totally, I will use this tool to reconstruct complex assembly-like models, i.e. single part, with both simple and complex weld shapes. For solid welds, I often create an offset profile along an edge of a body to be welded, e.g. 0.5" wide. Extrude this profile 0.5" as a new part. Round any corner edges as desired. Chamfer the part 0.5: Voila! You have a clean fillet weld, that can be integrated into the structure body. Sometimes, I've created the 0.5" wide profile along a snaking path, in and about lots of corners. Round corner edges. Chamfer 0.5". Done. So easy. No one else here uses this techniques (they use HM). I'm an I-DEAS dinosaur for a tools with an early death in 2020s. Perhaps, something like this could be implemented for Simlab CAD weld creation. and likewise for bevel/groove on weld prepped parts.
  6. I tried the Boolean of bodies on a more complex model. The Boolean worked to connect bodies. After 2D Mesh, Unmerge failed. Any possibilities? I did like the 2D mesh for boolean "connected" bodies. Last year, I struggled with clean mesh transitions between bodies, as I had varied element size too much between bodies. If the mesh size was doubled, transitioning from body to body moving away from stress-of-interest, the interface mesh was very clean after Remesh, i.e. transitioning from 2:1 mesh density. Darryl
  7. Can someone shed light on "Save Geom in Database", or not? I've had weird things happen when Checking this box, with zillions of apparent faces being imported rather than solids. But then it didn't repeat. Next time just the solid bodies. Which database? The model.slb file or a database somewhere else. It does not appear I should ever need to check that box, based on successful imports.
  8. VERY NICE! Just like an NX I-DEAS "partitioned" part!!! I like. I just tested with the Wheel and Cylinder from my Practice Step for Bolted Sprocket Drive forum post, ignoring the Sprocket Prior to meshing, used Geometry, Merge to Wheel and Cylinder into one body, keeping the common face. Meshed 2D the single Merged body. Unmerged the body back into the Wheel and Cylinder bodies Then 3D Solid meshed each body. Having the bodies separate is advantageous for a lot of reasons Did the usual LBC setup, and applied translational and vertical forces to 5 bolt holes, while xyz constraint to the wheel mount holes. Solved and displayed results to fruition. The two meshed bodies held together, without any need to remesh at the interface. The only difference with I-DEAS is that the single body must have a common average element size at the surface; whereas, I-DEAS could mesh each volume with totally separate element size. But still a very nice surprise. I supposed if one wanted to test further, one could Assembly, SEPARATE at the interface for whatever reason to actually split the mesh, and reconnect with MPC's for fun. Entire process took <20 min, just like a Marketing demo (or unlike if humongous transmission housing). Pretty cool, huh? Though totally different, Simlab is starting to remind of the good-old-days with I-DEAS Master Series, where one could demonstrate the entire modeling process from blank slate, 3D model and solid mesh to results in 10 minutes. Highly graphic, slick in many ways, i.e. Simlab. I'm very low (none) on work the next couple months as contractor during the lockdown, so I'll just keep learning these new tools like Simlab ... and Simcenter 3D (for where its appropriate to import large STEP asm's and revise geometry input to Simlab). Darryl
  9. Are the two body meshes still connected after UNMERGE? Or does this SEPARATE the two body meshes completely, ready for a smooth Assembly, Join operation, i.e. the joined meshes look perfect at the interface without ugly elements! I need to test. Only buggy (for me) 2019.3, and not 2019.2? If this works, I would prefer this technique to avoid ugly interface meshes upon Join and Remesh. Like I-DEAS "partitioned" bodies, in which the solid meshes transition smoothly across the partition.
  10. Can you provide a patch? Before I re-install a new version, I wish to see the Bolt Thread creation issue resolved (Bottom RBE2 with upward facing spider, not flat), and units problem for entering BAR depth and pitch as 0.25 and 0.05, versus 0.25in and 0.05in required for 2019.3 (a bug). I also noticed BAR elements ID's cannot be output with the BAR filter set; whereas, 2019.2 can do this. 2020 is released already?
  11. For further practice with bolted assemblies, a three-body STEP assembly was created for a Sprocket Drive in NX-IDEAS 6.1 (2004 version). This model is a spinoff of the Bolted Dome Assembly posted earlier. The slotted wheel section is a separate body, from the cylindrical section which is intended to be Joined to the wheel body. The sprocket and cylinder are adaptations of the dome and cylinder from the pressure box in earlier model, re-using bolt holes and pattern. For my simulation, the five mounting holes of the wheel were Constrained. A force of (6000, 4000, 0 lb) was applied at the fillet of one tooth as shown. The sprocket will be connected to the cylinder by 12 bolts. Your choice how to create. Manually create the flat spiders to washer faces (you create!), upward facing spiders near bottom of holes, and Bar elements connecting the spiders. Bolt Head creation, to automate creating the bolt head flat spider to washer face, and Bar element to the interface plane. Bolt Thread creation, to automate same for upward facing RBE2 and Bar element. I never succeeded getting this working, so they were easily created manually. Automated Bolt Head creation based on search of hole of size range, like the Altair demos, and same for Bolt Thread. Let me know if anyone gets the Bolt Thread feature to work, and how-to-do. I tried hard, and always failed with nothing displayed after the pop-up it had succeeded, and nothing new in the browser. Darryl Darryl SPROCKET_ASM.stp
  12. For practice with bolted assemblies, a simple three-body STEP assembly was created for a Dome Pressure Box. The base and cylinder are separate bodies. These can be Boolean or Join together for learning sake. Try the Boolean and learn to connect them as a single body with two volumes, and what that implies. Or Join the surface meshes and Remesh the interface, until a nice transition mesh is achieved. You may need to play with Mesh Controls on faces or edges for good transition. The domed body will be connected to the cylinder by 12 bolts. Your choice how to create. Manually create the flat spiders to washer faces (you create!), upward facing spiders near bottom of holes, and Bar elements connecting the spiders. Bolt Head creation, to automate creating the bolt head flat spider to washer face, and Bar element to the interface plane. Bolt Thread creation, to automate same for upward facing RBE2 and Bar element. I never succeeded getting this working, so quite easily created manually. Automated Bolt Head creation based on search of hole of size range, like the Altair demos, and same for Bolt Thread. Let me know if anyone gets the Bolt Thread feature to work, and how-to-do. I tried hard, and always failed with nothing displayed after the pop-up it had succeeded. The intention is to apply a 1500 psi internal pressure loading, e.g. a exploding device within, and compare stress contours in psi vis Simlab 2019.3. Bolts are 0.25" The solid assembly was quickly crafted in NX-IDEAS 6.1, with its superb and easy yet powerful modeler, but Windows updates may finally kill the great product. Darryl DOME_ASM.stp
  13. For new users, here's a simple STEP assembly of a solid welded block, with a round bar the user can attached as desired. With just four bodies, this assembly is a good way to practice and add to your skills. They are simple enough to try different techniques joining the bodies, or even b oolean. Here's an image on my practice model. The loop weld is joined to the base, block joined to the weld, and solid rod joined by MPC connection. The block is not joined by mesh to the base, as in the real welded part. The resulting stresses are shown for the same h3d file, for 2019.3 (left) and 2019.2 (right). There appears to be some difference in how the stresses are displayed for the two versions, but the queried stress is the same. Enjoy, and share and teach your newbies. Darryl TEST_SOLID_WELDED_BLOCK.stp
  14. Yes, feel free to use this simple model for Marketing Demo's, which I created in my own free time. Start to finish in 10 minutes.
  15. Just tried Boolean, CAD parasolid, Combine. Create connected bodies creates a single part, with one body for meshing. Help test implies it creates a single body with multiple bodies. If I volume mesh, the entire part is meshed. The help text implies a partitioning surface is created between the two bodies Boolean Combine. If I use cutting plane, the partitioning surface is visible in my simple model. But meshing is done across both volumes. How does one mesh each volume separately? What? Profile just upgraded from Beginner to Advanced in just 9 months from start? Xlent software.
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