diff --git a/CNC Machine.md b/CNC Machine.md index 29ffc68..272262b 100644 --- a/CNC Machine.md +++ b/CNC Machine.md @@ -12,6 +12,12 @@ The CNC (Computer Numerical Control) machine used in this lab is a large-format --- +#### Video - Full Explanation + +The video below showcases how the system works with explanation. + +--- + #### Safety Requirements Strict safety protocols must be followed when operating the CNC machine: @@ -31,6 +37,18 @@ Strict safety protocols must be followed when operating the CNC machine: --- +#### Design Requirements + +When designing for CNC cutting: +- Maintain at least **20 mm gap** between each design part. +- Keep designs at least **30 mm away** from each sheet corner. +- Ensure holes in your design are **larger than the drill bit’s diameter** so they can be cut cleanly. +- Select drill bits **larger than your material’s thickness** for full cuts. +- Export files in **DXF format** for compatibility. +- Double-check that the design size suits the tool (e.g., drill bit not larger than the smallest detail). + +--- + #### Debris Management The CNC machine includes a built-in vacuum system that removes debris generated during cutting. This ensures: @@ -56,7 +74,7 @@ Proper material positioning is crucial to cut accuracy. A **sacrificial sheet** **Tips for Alignment:** - Max sheet size: 2440 x 1220 x 12 mm (L x W x T). - If the sheet is curved, place the concave side down. -- Secure with bolts, ~30 mm away from corners and across the center. +- Secure with bolts placed within 20 mm of the corners and across the center. --- @@ -122,8 +140,8 @@ Proper speed and feed rate settings are critical for effective cuts: - **Feed Rate (in/min):** Determines how fast the tool moves across the material. For MDF using a 6mm tool: -- Optimal Speed: 17,000 RPM -- Feed Rate: 60 in/min (can vary based on tool condition and material) +- Optimal Speed: 8000 RPM +- Feed Rate: 80 in/min (can vary based on tool condition and material) Monitor chip formation and surface quality during tests to fine-tune settings. @@ -131,12 +149,10 @@ Monitor chip formation and surface quality during tests to fine-tune settings. #### Tips to Reduce Material Waste -- **Group Parts Efficiently:** Nest your parts close together in CAD to use the least amount of space. -- **Shared Cutting Lines:** When possible, let neighboring shapes share cut lines. +- **Group Parts Efficiently:** Nest your parts close together in CAD to use the least amount of space. [20mm space] - **Use Off-Cuts:** Save and reuse unused areas of the sheet for future small projects or test cuts. - **Add Labels:** Include engraved labels to organize parts and reduce re-cuts. - **Test on Scrap:** Run test cuts on scrap wood or corners before running the full job. -- **Design for Sheet Size:** Design parts to maximize standard sheet dimensions (2440 x 1220 mm). - **Minimize Tabs:** Use just enough tabs to hold parts in place without excess material. --- @@ -171,8 +187,15 @@ This section outlines the full workflow for using the CNC machine, from preparat --- -#### 3. Toolpaths: Cut +#### Assigning Cut/Pocket +Select the lines or shapes to define what will be cut or pocketed, then apply the relevant toolpath operation (profile/pocket). + +--- + +#### 3. Toolpaths: Cut + - Cuts along the outer or inner edge of a part. + - Defines the final shape by following the contour - Choose **Profile Toolpath**. - Set: - **Start Depth:** 0 mm @@ -188,38 +211,68 @@ This section outlines the full workflow for using the CNC machine, from preparat - Second Pass Depth: 13mm - Specify Machine Vectors: - Select **Outside/Right** for vector machining to preserve size. - - Select **Inside/Left** for - - Select **On** for -- Tabs: ++++++++ - + - Select **Inside/Left** for cutting internal shapes or holes. + - Select **On** for trimming directly along the vector line. - Click **Calculate**, then read the warnings, if it is within your expectations click **OK** to confirm. --- #### 4. Toolpaths: Pocket - -- **Pocket Toolpath:** - Used to hollow out an internal region. - Useful for engravings or fitting one piece into another. - - Cut Depth: As required (example: 5 mm). - - Start Depth: 0 mm. +- Choose **Pocket Toolpath**. +- Set: + - **Start Depth:** 0.0 mm + - **Cut Depth:** 2.0 mm +- Recheck "Tool" Parameters: + - Press "Edit": + - Geometry: + - Diameter: 6mm + - Cutting Parameters: + - Pass Depth: 6mm + - Stepover: 4.002mm || 66.7% + - Feeds and Speeds: + - Spindle Speed: 8000 RPM + - Feed Rate: 80 in/min + - Plunge Rate: 15 in/min + - Tool Number: 1 + - Press "OK" -- **Tabs:** +#### 5. Tabs - Small, uncut sections to keep parts attached to the sheet. - Prevents shifting or flying parts. - Size: Usually 3 mm wide and 2 mm high. - Automatically added in the Toolpath menu. + - Best used manually to avoid tabs at the edges. --- -#### 5. Preview Toolpaths +#### 6. Preview Toolpaths +- Go to the **3D View** tab. +- Click: + - **Reset Preview** + - **Preview Visible Toolpaths** +- If the toolpath appears erratic, the design may be **too small for the selected drill bit**. +- Fix it by: + - Returning to the **project tab** + - Resizing the design (drag from its edge) + - Or adjusting in your design software and re-exporting +- In the **Toolpath List**: + - Double-click **"Pocket 1"** + - Click **Calculate** +- Repeat the adjustment if the toolpath still behaves erratically. -Preview Visible Toolpaths -Click on the 3D View tab -Reset Preview -Preview Visible Toolpaths +#### 7. Changing the Drill Bit +- Turn off the CNC machine using the key (located at the bottom right) and remove it. +- Use two wrenches to loosen the collet assembly. + - Hold both wrenches in one hand to stabilize, and twist the lower wrench to loosen the collet nut. +- Remove the collet and clean both the collet and nut for a secure fit. +- Reinsert the collet into its housing. +- Insert the new drill bit, leaving ~20 mm (or two fingers) exposed for cutting clearance. +- Tighten the collet assembly firmly using both wrenches. +- Reinsert the key, power on the machine, and re-calibrate the Z-axis. -#### 5. ShopBot 3 Setup +#### 8. ShopBot 3 Setup - Open **ShopBot 3** software. - Load the toolpath file (.sbp). @@ -231,17 +284,17 @@ Preview Visible Toolpaths --- -#### 6. Z-Axis Calibration +#### 9. Z-Axis Calibration - Clip the wire to the collet nut or the spindle body of the CNC machine. - Place the **metal calibration plate** on the surface of the sheet. - Run the **Z-zeroing command** (machine lowers bit to touch the plate). - System detects contact and sets Z = 0. -- After calibration, remove the clip and plate, then return them to their original location with the clip still attached to the plate.This ensures smooth CNC operation. +- After calibration, remove the clip and plate, then return them to their original location with the clip still attached to the plate. This ensures smooth CNC operation. --- -#### 7. Start Machining +#### 10. Start Machining - Click **Start** to begin the operation. - Monitor the machine continuously.