Galaxy S4 Ballistic Case


Description: This is includes the CAD files needed to make the plastic portion of a Galaxy S4 Ballistic case.  Ballistic cases can be ordered here.  You need this part because it has the rubber portion of the case: recommend any color but blue because the other 3 colors come with black rubber which goes with any color.If you want an image on your case like mine, you have to find your own image.  Size it to the dimensions of the case (same width/length ratio 129X63).  Position the image so that it won't cover any of the holes in the case.  Just use a ruler might be easiest.  Or you can take a screen shot of the camera case and then load it into photoshop as another image layer.  Convert the picture to two tone black and white.  Then open the image with this utillity: 0.2mm for the base and .2mm for the target height. Why not base=0? to make it easier to align the image exactly perfectly with the case.  Set target width X to 129mm and height should automatically be 62mm.After this, optionally open the stl file in meshlab.  I reduced the faces to 1 million faces (so cura would be faster) using the "filters" "remeshing..." "quadratic edge collapse decimation".  I set quality to 1 as recommended in a shapeways article about this subject.Now special instructions - In your slicer (I used cura) flip the picture upside down, slice .2mm layers turn off brim or support or raft features.  Look at the slices carefully - you should have 2 layers. The bottom layer should be what you want as the image.  The next layer up you want to discard. Use a text editor to discard the second layer.Print this bottom layer using the first color of filament.  Again - it's important to slice both layers and then remove the upper layer only for purposes of alignment so when you print the phone case on top it will land exactly where you expected.  If you know better ways to align you can instead set the base height to 0 in image2STL and then you don't need to hand edit the gcode.Next, print the phone case on top.  With a different color filament of course.  You can even do this the next day or whatever.  When slicing the phone case you should somehow make it print .2mm higher than normal.  I did this with a G1 Z0.2 followed by a "G92 Z0" to make the printer think we are now at height 0. Alternatively you could slice the first layer as .4mm thick.  Or .35mm thick.  But I recomment .2mm layers for the rest of the print.Because the printer thought it was printing .2mm off the bed but was actually .4mm off the bed I had to increase the flow.  I used 150% but maybe I should have used 200%.  Once the first layer was done I put the flow back to normal.UPDATE: I added what you will need to do the UM Robot logo to any phone case or other print.  The stl file can be used to print a UM Robot.  It is scaled to 60 by 45mm but you can scale that in Cura to any dimensions.  make sure you flip it over by clicking on it in Cura, choosing rotate then rotate by 180 degrees using the green or yellow circles (not the red/Z axis circle).  I provided a screen shot of the first layer as one of my images for comparison.  Use .2mm and then hand edit the gcode and completely remove second layer in any text editor.  The gcode is well commented so it's simple to edit.  Search for "layer".  Alternatively you could have your finger on the power switch and after it finishes the robot and starts the border kill power and push head out of the way and remove any extra border filament.  Then you are ready to print anything you want on top.