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+*.FCBak

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+# Parametric D-Sub
+
+This is a FreeCad model that creates 3D printable D-sub housings.
+
+<img src="images/9pin.png" height=400>
+<img src="images/15pin.png" height=400>
+<img src="images/5pin.png" height=400>
+
+## Usage
+
+Open the Spreadsheet and adjust values as necessary. The only thing that
+should need to be adjusted is the number of pins, which should be an odd
+number because of how D-sub pinouts work. An even number will just give
+you the next lowest odd number.
+
+You might also want to adjust "Contact Hole" and "Contact Depth"
+depending on your contacts and the tolerances of your 3D printer. The
+housing depth is fixed at 11mm, which is approximately the depth of most
+manufactured housings. The flange-to-face distance is 5.8mm.
+
+Because of how the pins are repeated, the minimum number of pins is 3.
+There is theoretically no maximum. :D
+
+Sometimes changing the number of pins will cause the geometry solver to
+glitch and leave extra space on the right. If this happens, open the
+"D-Sub Outline" sketch (inside "Basic Shape"). Delete the tangent
+constraint on the upper right curve.
+
+<img src="images/tangent-broken.png" height=400>
+
+Then move the outline next to the reference box and reapply the tangent
+constraint between the curve and the vertical line.
+
+<img src="images/tangent-fixed.png" height=400>
+
+Close the sketch, and you should be good to go.
+
+## Print recommendations
+
+The flange is wedge shaped so that it can print without supports. This
+requires that it be printed face-up. This leaves a small amount of
+surface area in contact with the bed, which may need a brim for
+stability with your printer (FWIW it works fine on my Ender 3).