Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. dwallace1971

    Help for basic modelling

    The FEMAP documentation has a series of tutorials. This is a good place to start. I believe that this exact problem is presented. "On the human scale, the laws of Newtonian Physics are non-negotiable"
  2. dwallace1971

    High strength glass

    What is the application? Are there any limitations on thickness or optics? "On the human scale, the laws of Newtonian Physics are non-negotiable"
  3. dwallace1971

    Fuselage modelling techniques

    To add to what tbuelna said, when it comes to surfacing all 3D CAD tools are not created equal. The mid-level tools (Solid Edge, Solid Works, and Autodesk Inventor) are much less capable and I would be hesitant to model aircraft loft surfaces with those. The high end tools, CATIA, CREO, and NX...
  4. dwallace1971

    Femap Nastran Bullet ballistic analysis

    Do you own a license for the Advanced Non-Linear Solver? "On the human scale, the laws of Newtonian Physics are non-negotiable"
  5. dwallace1971

    Could I make a carabiner's pin/rivet out of copper instead of steel?

    kingnero makes a very good point. If you're making these in the U.S. and you don't want all of your profits to fund some injury lawyer's vacation home, you might have to ruin your design with that silly warning. "On the human scale, the laws of Newtonian Physics are non-negotiable"
  6. dwallace1971

    Gripping force

    Of what material are the two bits actually in contact with the rod you're trying to lift? "On the human scale, the laws of Newtonian Physics are non-negotiable"
  7. dwallace1971

    Cracking in PC/ABS (Chi Mei PC540) injection molded parts

    Have you tried drop-testing them since you've discovered the problem? Have you checked the fracture toughness of any of the damaged components? "On the human scale, the laws of Newtonian Physics are non-negotiable"
  8. dwallace1971

    Cracking in PC/ABS (Chi Mei PC540) injection molded parts

    How is the part loaded during assembly and operation? What are the environmental conditions in which it is used? What about UV and thermal cycling? "On the human scale, the laws of Newtonian Physics are non-negotiable"
  9. dwallace1971

    Rigid elements using Bar/Beam elements

    You could output your model as a .bdf file, then use excel to convert all of your bars to MPC's, then read them back into your model. It would ease the process if you renumbered your nodes prior to export to make the nodes you want as the dependent nodes to be lower or higher than the...
  10. dwallace1971

    FEA software for Flange analysis

    It seems you're looking for a "black box" solution to your problem, which suggests you really don't know what you're doing. As Brad805 pointed out, depending upon what question you're trying to answer, hand calcs should suffice. If you don't understand the physics of your problem, trying to use...
  11. dwallace1971

    cylinder sizing

    Additionally, you might add some carefully sized torsion springs at the hinge to assist your piston. "On the human scale, the laws of Newtonian Physics are non-negotiable"
  12. dwallace1971

    cylinder sizing

    You might have a very hard time rotating that to 90 degress in the configuration you have shown. As the frame rotates, the moment arm decreased until, near the end of the stroke, it's very small. It would work better if you moved your bracket attached to the frame out and ended the cycle with...
  13. dwallace1971

    Parametric Analysis

    What parameters are you wanting to vary? "On the human scale, the laws of Newtonian Physics are non-negotiable"
  14. dwallace1971

    Stress-Life (S-N) Fatigue Data Analysis

    Get yourself a copy of "Fatigue of Structures and Materials" by Schijve and read it. "On the human scale, the laws of Newtonian Physics are non-negotiable"
  15. dwallace1971

    Here's a new one for the times:

    Eric, don't lawyers sleep at night, too? "On the human scale, the laws of Newtonian Physics are non-negotiable"
  16. dwallace1971

    boundary conditions help

    If the only load you're imposing is thermal, consider a simple set of kinematic constraints to restrict rigid body motion. A quick google search will tell you all you need to know in order to set these up. "On the human scale, the laws of Newtonian Physics are non-negotiable"
  17. dwallace1971

    Tempered glass stars

    Chem-tempering tends to leave you with a much smaller case-depth, resulting in lower internal stresses. These internal stresses are what cause the shattering youd describe above. You may find that chem-tempered stars don't disintegrate into fine powder like thermally tempered stars might. "On...
  18. dwallace1971

    Solar Roadways

    I think the road to wealth in the future will be to design something of little actual value then convince politicians to mandate its use or to fund its development. Everything else will be regulated out of existence. "On the human scale, the laws of Newtonian Physics are non-negotiable"
  19. dwallace1971

    Solar Roadways

    But just think of the money you could make if you got the contract to build and replace all of those solar panels$$$$$$$$$ "On the human scale, the laws of Newtonian Physics are non-negotiable"
  20. dwallace1971

    Attachment Ship Hull - FE Boundary Condition

    Start with a free-body of the bit you want to know more about. That should give you a good idea of the loads and constraints you want to apply. I can't imagine you'd need to model the entire ship. If you have masses attached to your hardware of interest, you might be able to model those as point...

Part and Inventory Search