Poor milling precision

 cnc-milling, tips-tricks

1. Description of the problem

  • Shapes get deformed (square become trapezoidal, circles become ovals, etc...).
    • The measurement are outside the tolerance of your machine.

      2. Possible origins

      Inaccurate millings are usually caused by weak CAM strategy.

      3. Solution

      Here are a few goods practice rules which should enhance the quality of your millings. 

      1. Use "Stock-to-leave's " to split your operations in 2
        1. First rough out most of your stock leaving a few tenth of millimeter.
          1. Then bring to dimensions using one or multiple contour operations (without offset) to get a crisps and precise milling.
          2. Make sure you clamping is wright!
            1. You can never have enough clamps.
              1. Use double sided tape + screws/clamps to secure your piece if you are not sure of your clamping.
                1. Make sure the piece has is firmly secured in place and has no way to move.
                2. Be realistic with your feeds/speeds.
                  1. Go check out our recommended Feeds and speeds as a base and adapt to your situation (end mill quality, material, etc...) .