Facing the Spoilboard (Otherplan Classic)
This guide refers to Otherplan Classic, OMC’s legacy application for Mac OS X. For the cross-platform version of this guide, please click here.
Occasionally a tool will gouge the surface of your Othermill’s spoilboard. The spoilboard is intended to incur occasional scratches, and they generally won’t have much of an effect on milling accuracy. However, sometimes you just need to start fresh. Otherplan Classic comes with a built-in feature called a facing plan, with which the Othermill can machine off a tiny amount of a material’s surface to make it smooth and level. In case of gouges to the spoilboard, the mill can face its own spoilboard to maintain a smooth and level surface.
How to Face Your Spoilboard
First, make sure all fixturing, brackets, and material are removed from both the spoilboard in the machine and in Otherplan Classic (click the Setup Fixturing button in the upper-right corner of the Otherplan Classic window to remove the alignment bracket if you have it enabled in the software).
In Otherplan Classic, with BitBreaker Mode enabled (Otherplan > Preferences > check the BitBreaker Mode box), click on “Add Facing Plan” in the “Plans” panel.
Insert a 1/8" flat end mill into the tool holder, and run the tool locating sequence.
In the Setup Material panel, select Anodized Aluminum and set the Width (x) to 5.5in (139.7mm) and the Height (y) to 4.5in (114.4mm). The material thickness (z) should be set to 0.1in (2.54mm).
In the next dialog box, “Set The Material Origin”, leave the x and y at 0. Change the z value to -0.1in (-2.54mm). Note the negative value! Click Done.
In the “Advanced…” button back in your plan file, change the default values for the following items to the values below:
Feed Rate: 59in/min (1500mm/min)
Plunge Rate: 1.5in/min (40mm/min)
Spindle Speed: 16,400rpm
Click the green check to keep your changes.
Using a Sharpie or other permanent marker, draw lines all over your spoilboard. If any lines are still there after running the facing plan once, run it again. Otherplan will automatically compensate for the amount of material removed from the spoilboard, so there’s no need to re-set the material dimensions.
Go over your settings for tool, material, and facing plan, and double-check that they’re correct. Clear the spoilboard of any material, tape, or debris. Make sure your windows are in place as well.
Make sure you have everything you need to settle in for a while (a good book, a glass of juice) and click on “Start Cutting”. The machine will ask you to confirm. Once you’re ready, click on “Cut!” and your machine will begin facing its own spoilboard.
Remember, a running machine should never be left unattended!
Start with a nice fresh setup for all your tools and materials. Locate your spoilboard, locate your tool, and clear all the values for the material and start fresh. There’s nothing worse than having disaster happen because one small setting was skipped.
For facing the spoilboard, set the tool before you set the material. If the material covers the whole spoilboard, Otherplan Classic will not allow a tool touch-off.