I had initially cut a simple cat outline to test the system in some aluminum tread plate I had in garage about a month ago.
Today I cut 14 GA steel using a file I created from scratch within Fusion 360. Most all of entry/ end points of cuts caused some problems with incomplete cuts. I was able to remove them and easily grind off the dross. I had the Razorweld X45 set at 42A and 140ipm.
Here is the export from Fusion 360 with G code. bahtinov-mask.nc (17.1 KB)
The finished product is here and should work ok. This is placed on the end of a telescope to focus the stars - called a Bahtinov Mask. It’s used for just a couple minutes to focus then set aside. For reference, it is ~ 11 inches in diameter:
Finally, I noticed each time the torch shuts down between piercings, there is a lot of air that continues to exhaust. It seems something is wrong. Should air completely stop when the torch shutdown?
I routinely use MS Copilot and ChatGPT. Recently X made Grok available to everyone. I uploaded two of the pictures above to Grok and asked what are the problems.
Here’s the response:
The issue with incomplete cuts at the entry and final cut points in your CNC plasma cutting process can stem from several factors:
Pierce Delay: If the plasma torch isn’t given enough time to fully penetrate the material before moving, this can result in incomplete cuts at the start. Adjust the pierce delay or pierce height settings for a cleaner start.
Cut Speed: Starting or ending the cut too quickly can lead to incomplete edges. Ensure that your machine slows down appropriately at the start and end of cuts. Some machines have a ramp-up and ramp-down feature for the cutting speed which can help.
Torch Height: If the torch is too high or too low, it might not cut through completely. Verify that your torch height control (THC) is functioning correctly and calibrated for the material thickness you’re cutting.
Gas Pressure and Flow: Incorrect gas pressure or flow can affect the cut quality, especially at the beginning and end of the cut where the plasma arc might be less stable. Check your gas settings and ensure they are optimized for your material.
Material Clamping: If the material isn’t securely clamped, it might move during cutting, leading to inconsistent cut quality. Ensure your material is well-secured.
Consumables Condition: Worn or incorrect consumables can lead to poor cut quality. Regularly check and replace your plasma torch consumables.
Lead-ins and Lead-outs: Design your lead-ins and lead-outs properly. A short, straight, or overly aggressive lead-in can cause issues. Consider using a longer, more gradual lead-in for better cut initiation.
Post-Processing: Sometimes, even with optimal settings, a slight touch-up might be needed at the entry and exit points. Using a grinder or a deburring tool can clean these up if they’re not too severe.
Here’s a quick checklist for troubleshooting:
Check your pierce settings: Ensure enough time for the plasma to pierce through before moving.
Review cut speed settings: Adjust for a slower start and finish if necessary.
Verify torch height control: Make sure it’s correctly set for your material.
Inspect gas settings: Ensure proper pressure and flow.
Secure material properly: Use adequate clamping.
Maintain consumables: Replace when necessary.
Optimize lead-in and lead-out paths: Ensure they are not too short or aggressive.
If these adjustments don’t resolve the issue, there might be a need for more detailed diagnostics of your machine’s settings or even hardware issues that might require professional attention.
For the incomplete cuts, do you have any overlap distance set in Fusion Toolpath? If not, you might try adding a tiny amount. It’s on the “Passes” tab (4th tab) when setting up Toolpath parameters.
