Double-Sided Boards (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.

This video shows how to make double-sided boards on the Othermill, using Otherplan Classic, as does this guide. If you haven’t yet completed the Bracket Locating and Tool Locating tutorials, you’ll need to do that before milling a double-sided board.

Setting Up Your Board and Software

1. Ensure that the bed is free from all debris, paying special attention to the inside edges of the bracket. Ensure that nothing is between your material (e.g. tape, glue) and the bracket. Anything that prevents solid, clean contact between your material and the bracket may result in misalignment.

2. Place your material on the machining bed in the bracket, with the lower edge of the material flush to the corner of the bracket.

Pro Tip: For best results, first right-click your material, then select Align To → Bracket. This will move your material to the correct bracket corner and cause it to stick. Now, if you toggle the Side button in Otherplan Classic, your material will be flipped between the opposite corners of the bracket and any plans you have imported will also be turned over (.tap and .nc files are not flipped).

Screen Shot 2015-02-17 at 12.38.27 PM

3. Place your material in the lower left hand corner of the bracket when cutting the Top side. Place your material in the lower right hand corner of the bracket when cutting the Bottom side. Before cutting, always double-check that Otherplan is showing the material in the same corner where it is physically positioned in the Othermill.

WARNING: It’s possible to cut into the bracket accidentally! Make sure any plans are clear of the bracket rendering on the machine bed, and make double sure you have executed the full bracket probing sequence under the Setup Fixturing panel.

Otherplan Classic will warn you about possible collisions by drawing a red-and-black warning pattern over possible collision regions and by showing a warning dialog before you begin cutting. If you see warnings, be sure to double-check whether you need to move your material or plan.

Screen Shot 2015-02-17 at 12.48.32 PM

4. To cut the top side, double-check the measurements of your board with calipers to ensure the material size in Otherplan Classic and the actual board are the same size. Boards can vary, and being even a few thousandths off in the x- and y- axes could cause your holes to misalign.

5. Load in the FR-1 as described (don’t forget to use an even layer of double-sided tape to stick it down to the bed!). Choose your tool, material, and other settings in Otherplan Classic. If you need a refresher on how to do this, see our Hello World project.

For best results, on the top side, cut only the traces and holes. When the top side traces and holes are done, the machine will stop. In Otherplan Classic, toggle the Side button to “Bottom”. You’ll see the rendered board on the Otherplan Classic spoilboard flip over and align itself to the lower-right hand corner of the bracket.

6. Remove the FR-1 from the Othermill’s spoilboard. Flip the board over, remove the tape from the bottom on the board, and put an even layer of double-sided tape across the side of your board you just milled. Be careful for small, delicate traces as you apply the tape to the finished side!

7. Align your board to the lower right-hand corner of the bracket. Make sure the board is tamped down securely.

8. Make sure everything is set the way you want it, both on the machine and in Otherplan Classic, and click on “Start Cutting” to machine the bottom side of your board.

9. When the bottom cut is finished, including the outline, you should end up with a nicely aligned, double-sided board ready for you to place your components.

If you run into trouble, feel free to email us at and we’ll give you a hand.