Diamond Drag

[kstrauss]

I often use a diamond drag engraving tool to add serial numbers and such to projects. A diamond drag tool doesn't rotate so the spindle speed for it is set to zero. It works great. Ages ago (perhaps VCarve v8?) I added my diamond tool to the tool database and have moved things forward unchanged with each new release. With VCarve 10.512 when I attempt to modify the tool database for this tool I get a message that "Spindle speed must be greater than 0" and VCarve refuses to save the updated tool entry. What should I do?

[Rcnewcomb]

Define it as a diamond drag bit in the tool database

[kstrauss]

Thanks! I wonder when that tool type was added. Does it do anything special other than letting you set the spindle speed correctly?

[Rcnewcomb]

In addition to allowing the spindle to be off, the diamond drag tool interacts with the Quick Engraving toolpath with some intelligence.

From the Help manual:
Depth / Pressure
When using Conventional Engraving and End Mill cutters the Depth to engrave / mark is specified and this z depth dimension is output in the toolpath file sent to the CNC machine. The 3D Preview of these toolpaths shows the specified depth of engraving.

When using a Diamond Drag marking Tool the Pressure setting is used to pre-load the spring to ensure the tip of the diamond stays in contact with the material surface, especially when marking uneven surfaces. The 3D Preview of the depth these toolpaths will mark using the Angle of the diamond and the Width of the Line.

For example, when using a 90° Diamond Drag Tool with a 0.010 inch Line Width specified. The depth shown in the 3D preview will be 0.005 inch (with 90° the depth = half the line width).

The ratio of Depth to Line Width will change when using diamond drag tools with different tip angles. When the option to use a Nose Cone is selected (see below) the actual depth specified on the form is used when previewing the toolpath in the 3D view.