{"id":207,"date":"2022-07-14T23:08:00","date_gmt":"2022-07-14T15:08:00","guid":{"rendered":"https:\/\/acomold.com\/how-to-evaluate-a-mold-design.html"},"modified":"2023-07-26T18:08:59","modified_gmt":"2023-07-26T10:08:59","slug":"how-to-evaluate-a-mold-design-2","status":"publish","type":"post","link":"https:\/\/www.acomold.com\/how-to-evaluate-a-mold-design-2.html","title":{"rendered":"How to evaluate a mold design?"},"content":{"rendered":"

Mold design<\/a> is the start of any successful mold-making project, so a careful evaluation and optimization process is very much necessary, review the design to verify the plastic parts requirements and mold manufacturability are all satisfied.
\n\"Mold

    \n
  1. \n\t\tIs there a “parts to customer” promised date?<\/li>\n
  2. \n\t\tHas the mold completion date been established?<\/li>\n
  3. \n\t\tHas the cavity level been established?<\/li>\n
  4. \n\t\tHas the mold cost<\/a> quote been completed?<\/li>\n
  5. \n\t\tHas the cycle time been established?<\/li>\n
  6. \n\t\tHas the material to be molded been determined?<\/li>\n
  7. \n\t\tIs existing product available?<\/li>\n
  8. \n\t\tIf 7 is yes, should the existing gate location be used?<\/li>\n
  9. \n\t\tIf 7 is yes, is the product symmetrical in design?<\/li>\n
  10. \n\t\tAre maintenance costs built into the price?<\/li>\n
  11. \n\t\tIf there is existing product running, is it running under deviation?<\/li>\n
  12. \n\t\tAre there gages available for this product line?<\/li>\n
  13. \n\t\tIf there are no gages available, will they be available when the construction is completed?<\/li>\n
  14. \n\t\tGiven the proposed cavity level, will the product fit into one of the three standard size modules?<\/li>\n
  15. \n\t\tIs the shrinkage data available at this time?<\/li>\n
  16. \n\t\tIs there an existing or similar product for which reliable shrink data is available?<\/li>\n
  17. \n\t\tShould the tool be designed for “steel safe?”<\/li>\n
  18. \n\t\tHas a product polarization feature been identified?<\/li>\n
  19. \n\t\tAre Pro E models available?<\/li>\n
  20. \n\t\tWhat level of tooling supports the business?<\/li>\n
  21. \n\t\tCan the part date code (clock code), if applicable, be changed without removing the mold from the press?<\/li>\n<\/ol>\n

    Cavity<\/strong><\/p>\n

      \n
    1. \n\t\tAre slender inserts protected from injection molding<\/a> pressure?<\/li>\n
    2. \n\t\tAre sliding areas made of dissimilar steel, hardness or coatings?<\/li>\n
    3. \n\t\tIs stationary-half ejection necessary?<\/li>\n
    4. \n\t\tIs cavity construction strong enough to prevent deformation due to clamp pressure?<\/li>\n
    5. \n\t\tShould core pins be piloted?<\/li>\n
    6. \n\t\tIs mismatch needed to maintain critical dimensions?<\/li>\n
    7. \n\t\tDo cavity blocks have benching pins?<\/li>\n
    8. \n\t\tAre fragile areas of cavity inserted?<\/li>\n
    9. \n\t\tAre cavity inserts backed up by hardened steel?<\/li>\n
    10. \n\t\tProper steel type specified for various components?<\/li>\n
    11. \n\t\tProper plating(s) specified?<\/li>\n
    12. \n\t\tProper polish(es) and draw polish specified on tool drawings?<\/li>\n
    13. \n\t\tIs gate area inserted?<\/li>\n
    14. \n\t\tHas cavity been properly vented?<\/li>\n
    15. \n\t\tDo vents<\/a> reach atmosphere or vacuum?<\/li>\n
    16. \n\t\tHas cavity been evaluated for ease of maintenance?<\/li>\n
    17. \n\t\tHas gate puller been provided for a gate in moveable half?<\/li>\n
    18. \n\t\tIs draft present for telescoping tooling?<\/li>\n
    19. \n\t\tIs sufficient draft present for a side release and part ejection?<\/li>\n
    20. \n\t\tIs cavity sequence definition necessary?<\/li>\n
    21. \n\t\tHas computer analysis been done for runner sizes?<\/li>\n
    22. \n\t\tIs any steel telescoping less than 3 degrees?<\/li>\n
    23. \n\t\tIf steel is telescoping less than 3 degrees, can this be increased?<\/li>\n
    24. \n\t\tIs strip action required on A side?<\/li>\n
    25. \n\t\tIs strip action required on B side?<\/li>\n
    26. \n\t\tDo internal detentes require either half core to float out prior to ejection?<\/li>\n
    27. \n\t\tHave “key features” been identified?<\/li>\n
    28. \n\t\tDoes the “key feature” dimension correlate with the area of the product most functionally critical and that will be most affected by process changes?<\/li>\n
    29. \n\t\tAre ejector pins located at intersection of runners?<\/li>\n
    30. \n\t\tHave runner cold-slug wells been vented?<\/li>\n
    31. \n\t\tWill the runner stay on the ejector side of the mold frame?<\/li>\n
    32. \n\t\tIs the sprue bushing retained in the mold frame?<\/li>\n
    33. \n\t\tWill the nozzle area of sprue bushing trap material?<\/li>\n
    34. \n\t\tIs an ejector pin properly located to eject the gate?<\/li>\n
    35. \n\t\tHas sprue length and diameter been minimized?<\/li>\n
    36. \n\t\tDoes cavity need alignment feature to protect steel (for cavities without frames)?<\/li>\n
    37. \n\t\tHave complete parts lists been drawn?<\/li>\n
    38. \n\t\tAre all drawings properly numbered?<\/li>\n
    39. \n\t\tAre set-up sheets prepared for multiple part numbers?<\/li>\n
    40. \n\t\tAre interchangeable inserts polarized?<\/li>\n
    41. \n\t\tWas any texture requested?<\/li>\n
    42. \n\t\tAny special requests made by Manufacturing Department?<\/li>\n
    43. \n\t\tWas vacuum requested for vents (end of fill or full vacuum depending on product)?<\/li>\n
    44. \n\t\tAre enough ejector pins present for short shots?<\/li>\n
    45. \n\t\tWere “pull grooves” requested or needed?<\/li>\n
    46. \n\t\tCavity identification called out on the tool drawings?<\/li>\n
    47. \n\t\tCircuit identification called out on the tool drawings<\/li>\n
    48. \n\t\tProper company logo called out on the tool drawings?<\/li>\n
    49. \n\t\tBroken corners to be shown only to aid in handling\/shut off clearance.<\/li>\n
    50. \n\t\tIs the polymer material code engraved in the cavity?<\/li>\n
    51. \n\t\tAre the runners vented?<\/li>\n
    52. \n\t\tDo units stand proud from frame for shut-off?<\/li>\n
    53. \n\t\tHas a hot sprue been considered?<\/li>\n
    54. \n\t\tAre there separate jack screw holes for face-mounted units?<\/li>\n
    55. \n\t\tHas product been reviewed for max core out of material?<\/li>\n
    56. \n\t\tAre wedge locks installed?<\/li>\n<\/ol>\n

      Ejector System<\/strong><\/p>\n

        \n
      1. \n\t\tIs ejector travel greater than length required for part and runner ejection?<\/li>\n
      2. \n\t\tAre stop pins provided to limit ejector travel?<\/li>\n
      3. \n\t\tIs frame travel limited to less than cavity travel on face mounted cavity units?<\/li>\n
      4. \n\t\tAre ejector pins, support pillars or ejector sleeves not interfering with knockout holes?<\/li>\n
      5. \n\t\tIs strength of ejector plate compromised by use of support pillars?<\/li>\n
      6. \n\t\tWill hand-loaded inserts stay on their locator pins at top of full ejection stroke?<\/li>\n
      7. \n\t\tIs ejector system guided on class 1 and precision molds?<\/li>\n
      8. \n\t\tCan the ejector plates be pulsated to flick plastic parts off of the ejector pins?<\/li>\n
      9. \n\t\tIs an “early return” system required?<\/li>\n
      10. \n\t\tDo compression springs use an operating range (25-35% of free length)?<\/li>\n
      11. \n\t\tAre “cushioned” return pins required when ejector pins are on a clamping parting-line surface of cavity?<\/li>\n
      12. \n\t\tAre stripper plates of adequate thickness?<\/li>\n
      13. \n\t\tHave additional screws and stop buttons been added to ejector plate sets on larger die casts?<\/li>\n
      14. \n\t\tIs a hydraulic return required?<\/li>\n
      15. \n\t\tAre safety limit switches installed on die cast having ejector devices inside of slide paths?<\/li>\n
      16. \n\t\tAre springs required to return ejector plates?<\/li>\n
      17. \n\t\tCan ejector plates be tied in to the press?<\/li>\n
      18. \n\t\tAre cold slugs 2 times the runner diameters?<\/li>\n
      19. \n\t\tOn sub-gated parts, is the ejector pin located for proper gate ejection\/runner flex?<\/li>\n
      20. \n\t\tDo all runner intersections have a radius?<\/li>\n<\/ol>\n

        Temperature Control System<\/strong><\/p>\n

          \n
        1. \n\t\tHas mold cooling<\/a> analysis been done?<\/li>\n
        2. \n\t\tAre frame and cavity designed for pulse cooling?<\/li>\n
        3. \n\t\tAre cooling line connectors recessed?<\/li>\n
        4. \n\t\tWill fitting locations interfere with tie-bars or clamps?<\/li>\n
        5. \n\t\tAre fittings that extend beyond exterior of mold frame protected from damage?<\/li>\n
        6. \n\t\tIs there a 3\/16″ min. wall surrounding cooling lines?<\/li>\n
        7. \n\t\tAre there sufficient cooling lines in the following areas:<\/p>\n