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Material Library

Discussion in 'Using Alibre Design' started by bigseb, Aug 6, 2015.

  1. bigseb

    bigseb Alibre Super User

    I want to make a copy the default material, edit and add to it and then use that. That's not possible apparently so I have to create one from scratch. I'm a bit stuck though. I looked at 'alibre_unicode_sample.mtl' and from that I don't quite get how to set up the new library. Can anyone share one of theirs to give me a jumping off point.

    Also not quite sure where save this new library. Does it overwrite the old one or will the values of both be visible (not ideal).

    Thanks.
     
  2. DavidJ

    DavidJ Alibre Super User

    Seb,

    I set up a custom file some time ago - really just as an example to show to a customer who wanted to do his own. I've attached my file for what it's worth. Just place it in the same folder as the sample file.

    EDIT - .mtl extension not allowed - I'll re-name it or something - change it from .doc to .mtl before trying to use.
     

    Attached Files:

  3. bigseb

    bigseb Alibre Super User

    Thanks David,. Waiting eagerly.

    I also downloaded Lew's "Alibre_Unicode_Custom_Metals_Workbook.ods" form GrabCAD. It contains a ton of info but nothing on how to set it all up...
     
  4. DavidJ

    DavidJ Alibre Super User

    My file is deliberately very simple - it sets up a new group and just 2 or 3 materials - should be pretty obvious, but feel free to ask specifics. As I recall, finding the name of the hatch patterns was the tricky bit (has to match the pattern file, but I've a funny feeling there is a slight difference in format between files).
     
  5. DavidJ

    DavidJ Alibre Super User

    Now IF it works like custom threads - an EXACT name match with a built in material will override the default one. Perhaps someone from Geomagic could clarify for us ?
     
  6. bigseb

    bigseb Alibre Super User

    Basically I'm at a point now where I have collected all my material data (specific to all the materials that I actually purchase and work with locally) but I have no idea how to write out a new library. Stuck.
     
  7. DavidJ

    DavidJ Alibre Super User

    Each material has its own line in the file, the line MUST commence with an asterisk. Fields are separated by commas.

    * Material Name, density value, mass unit for density, distance unit for density, Class Name , Pattern or patterns for cross section hatch (to match pat definitions)


    That is it - Class Name is useful if you want to group materials together, or presumably fit into an existing standard class of material.

    mass unit and distance unit are chosen to match those of the density figure you define (e.g. g/cm3 or kg/m3 ).

    I used extra spaces in my file to keep each entry somewhere close to below the title - I started from a copy of the sample file.

    File MUST be saved in Unicode format or it won't work at all.
     
  8. Lew_Merrick

    Lew_Merrick Alibre Super User

    Sebastian,

    In essence, each line starts with an asterisk (*). The material designation follows that on the line and should be enclosed in quotation marks (") to allow commas (,) to be embedded in the definitions (something I historically have failed to do). Comma (,) separator. The density of the material in appropriate units. Comma (,) separator. Mass unit (lbm, gm, or kg). Comma (,) separator. Length unit (in, ft, m, cm, mm). [The "density" must be provided in Mass/Length³ units.] Comma (,) separator. "Class" of material (used to segregate things in your listings). Comma (,) separator. Name of Hatch Pattern to be used in the drawing module.

    Comment lines start with a double-semi-colon (;;). [I use this to segregate materials by "class." Hence, my aluminum materials are "classed" into: Alum-Non-HT, Alum-HT, and Alum-Cast classifications.]

    Now, (1) being an American for whom 90+% of my work and experience is based in lb/in/sec units, all my data assumes that as the foundation; and (2) I use the (American Department of Defense) MIL-HDBK-X classifications as that is what I normally am required to use. These factors "color" my approach. On top of that, I have used several different approaches in "designing" the spreadsheets I use to maintain my various "entries" that are combined into my alibre_unicode_custom.mtl datasets. It has been an "evolutionary" process and is not consistent!

    Now, to be clear, my argument is that we should allow several materials libraries to be available and user-selected as required. My datalsets are constructed around American material designations. There should be such datasets for other standards (British, EU, and JIS leap to what's left of my mind). My hope has been that others would leap into this breech and supply such information -- and that has not happened as nearly as I can tell!

    In any case, the attached ZIP file has LibreOffice Calc spreadsheets aimed at collecting data for: (American) Metals, Bolt Materials, Spring Wires, and Elastomers.
     

    Attached Files:

  9. bigseb

    bigseb Alibre Super User

    Thanks guys. Gonna spend some time playing around with this... :D
     
  10. GIOV

    GIOV Senior Member

    Are all of these materials as part of the JCSS Accredited Calibration Laboratory covered by the International Mutual Recognition Arrangements (MRA) based on JIS Q 17025 (ISO/IEC 17025)? I thinks the JCSS are approved by the most of the Classification Societies as ABS ,DNV ,LRS ,RINA ,ClassNK, BV.. Insurance Issue.
     
  11. Lew_Merrick

    Lew_Merrick Alibre Super User

    I assume this was aimed at me. No, these datasets are based on US standards (MIL, ASTM, ASME/ANSI, etc.). JIS (Japanese Industrialization Specification) and ISO (International Standards Organization) operate to a completely different identity & testing specification set.
     
  12. GIOV

    GIOV Senior Member

    Ok Lew,
    It is important that you first Parametric Material, fasteners, tubes, girders profiles' library for Alibre & GD is updated to the latest issued report of the Standards Organizations.
     
  13. Lew_Merrick

    Lew_Merrick Alibre Super User

    Giov,

    1) Material properties are only Parametric in that they are dependent upon loading rates (sometimes called energy transfer rates) and temperature. A parameter is a variable controlled by an external function. This is an error in understanding that has crept into usage in contradiction to the fundamental mathematical definition.

    2) Which Standards Organization are you referencing. There are five such organization making up the (now so confused they cannot do anything right) International Standards Organization (ISO). Ever since America replaced the National Bureau of Standards with the National Institute of Standards and Technology (in 1986), we (Americans) have been losing out to corporate claims of intellectual property (the protection of which is the only positive action required under the NIST Charter). This is why I insist on basing my data on reputable sources for such information -- such as MIL-SPEC, ASTM, ASME/ASCE, NAS, and the like. In point of fact in my spreadsheets, if a value has a yellow background it means that it derives either mathematically or from unvalidated test data. The primary data point so identified is minimum shear strength values derived from Moh's Diagram analysis.

    3) As the alibre_unicode_custom.mtl dataset only includes density (assumed to be at 68°F/20°C), the rest is moot.

    Now, if you are talking about the dataset supplied with any of the Design Simulation Technologies add-on products, you are so far away from reality as to have no hope of recovery. They make the (lousy) SolidWorks datasets look good. Even their (DST's) base temperature is wrong!

    This is not to say that everything I do is perfect. My fingers are as dyslexic as anybody else's are...
     
  14. GIOV

    GIOV Senior Member

    I understand the parametric mathematical concept regarding to you fasteners tubes, girders profiles. For the materials properties I am far away.
    I am referencing to the Lew Merrick Standard as Reference for re-check an specific Standards Organization Material properties Values for apply a feasible Factor of Safety (safety Factor)
    Some Fem software don`t toll if the material are Heat or not Heat Treatable Alloys and How these values changes due cyclical loading, vibration and/ or high temperatures, so the risk of fatigue may be incremented and the Factor of Safety must be corrected.
    Suggestion for you head Column names:
    Yield Stress = >Yield Strength,
    Ultimate Tensile Stress= >Ultimate Tensile Strength,
    Maximum Shear Stress=> Maximum Shear Strength.
     

    Attached Files:

  15. Lew_Merrick

    Lew_Merrick Alibre Super User

    As noted, my data comes from sources such as MIL-HDBK-5 and other recognized by my cited references sources. Values are the minimum values that meet the accepted specification. Factors of Safety or Margin values must be determined in accordance with the application.

    Strength is determined by the application. Allowable Stress (within recognized limits) is a property of the material.

    Now, if you are expecting commercial FEA datasets to provide you with more than generally recognized values for critical or non-standard loading conditions, then you are courting disaster! Few outside of industry specific standards (particularly aerospace, military, or specific medical device -- costly) programs will even make the attempt to provide such information. That is the outsider's ongoing problem. Having worked in many such places, I have acquired a great deal of such data that would otherwise have cost many tens of thousands of dollars. [Don't shade your eyes, but plagiarize -- only always call it, please, research!]
     
  16. GIOV

    GIOV Senior Member

    I think the concept are good explained by a professor of the MIT, your alma mater.
     

    Attached Files:

  17. Lew_Merrick

    Lew_Merrick Alibre Super User

    Whereas I have worked at a number of MIT laboratories over the years, what passes as my alma mater is Seattle University.
     
  18. GIOV

    GIOV Senior Member

    keep you out from organizations with secret initiations who are the origin of the many, many human troubles and innocents victims.
     
  19. bigseb

    bigseb Alibre Super User

    Finally got around to playing with this. All going well until I saw this:



    Seriously?! Aluminum?! Fix it please Geomagic... its an embarrassment... :roll:
     

    Attached Files:

  20. bemfarmer

    bemfarmer Senior Member

    It is called that in the UK
     

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