Introduction

It's possible to add easily holding tabs in bCNC. These tabs prevent the piece from moving during the cutting.

Example with an Inkscape G-Code file

To illustate, I work with an Inskcape G-code file. In this file, we have a circle with 20mm thickness and a depth step of 5mm. So there are 4 passes (the first at -5mm, then -10, -15 and -20mm for the last).

1. Find the last block (last pass)

In the Editor, we see 6 blocks of G-code and the last pass is in the 5th block (the second last). We select this block because it's here that we are going to add the tabs. Other way : you can select also the last path (the deepest) in iso view.

2. Adjust the "Tabs" parameters

Then in the tools tab, click on the "Tabs" icon. Adjust the parameters :

• The number of tabs (here 3)
• The height of the tabs (here -17) : it's the height where the bit rise to cut the tabs (the top of the tabs). As the last pass is at -20, so the thickness of the tabs is 3mm. Then click on the "Execute" button -> 3 orange squares appear.

3. Adjust the "Cut" parameters

Then click on the "Cut" button. Adjust the parameters :

• Surface Z : 0.0
• Target Depth : -20 (the height of the last pass)
• Depth Increment : -20 (the height of the last pass)

Then click on the "Execute" button -> we see 3 new tabs on the last pass.