07-17-2025 Q&A: Downcut Fuzzies, Rotary Raster Angles, Thread Milling, and Scaled Rotary Bats

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In this Q&A session, we tackled issues ranging from downcut bit fuzzies and toolpath marks to rotary carving optimizations and thread milling for mason jars. We also covered how to scale down a rotary baseball bat model and explored various dust collection options for rotary setups.

Key Tips Learned in this Q&A:

• Reduce Fuzzies with Upcut Bits: When cutting poplar, switching from a downcut to an upcut bit can significantly reduce fuzzies at the bottom of a cut. Keep your bits sharp for best results.

• Toolpath Mark Solutions: To eliminate toolpath marks (dwelling marks), enable both lead-in/lead-out and ramp options in your toolpath settings. However, “Do Separate Last Pass” may override these unless done manually.

• Rotary Raster Angle Fix: If your rotary toolpath is causing bi-directional rotation and climb cutting, change the raster angle to 0° (or 180°) so it moves along the rotary length, not around it.

• Thread Milling Limitations: Aspire's internal threading toolpath has pitch limitations tied to bit geometry. Wider threads like those on mason jars may require a different bit or custom tooling.

• Scaling Rotary Projects: To scale rotary models like a baseball bat, uniformly resize both the profile and the rail, then update toolpaths and re-center them for proper carving.

Questions Answered in this Q&A:

• 00:00:02 – Why does my downcut bit leave fuzzies and toolpath marks on poplar?

• 00:18:49 – How do I prevent rotary toolpath from reversing direction and causing climb cuts?

• 00:21:43 – How can I create multi-color inlays like “I ❤️ You”?

• 00:22:43 – How do I mill coarse internal threads for mason jars in wood using Aspire?

• 00:38:32 – Is MDF a good test material for 3D carving?

• 00:42:10 – What are options for dust collection during rotary carving?

• 00:44:15 – How can I scale down the rotary baseball bat project properly?

• 00:51:21 – Can clipart be modified in VCarve Desktop to change depth?

Keywords:

cnc, vectric, rotary carving, poplar fuzzies, toolpath marks, do separate last pass, ramping, raster strategy, rotary toolpath, internal threads, thread milling, mason jar, rotary baseball bat, mdf 3d carving, dust collection, clipart editing vcarve, learn your cnc