Learning to CNC
Overview
I've always been infatuated by CNC machining, but I haven't had the opportunity to work with one hands-on. This summer, I spent 15 hours per week in the Seattle University machine shop teaching myself how to do CAM programming and CNC machining.
Top Skills Utilized
Fusion 360 CAM
SOLIDWORKS
GD&T
4th Axis
Soft Jaw Workholding
Starting out
Familiarized myself with the Haas CHC (Classic Haas Control): jogging, overrides, file loading, MDI coding, tool and work probing.
Probing
Learned to properly probe work with a Renishaw touch probe, picking up outer corners, bores, center of bosses, and adding automatic probe operations in Fusion CAM to reduce cycle time.
Additionally, learned to touch off tools with work probe, and created and maintained a cloud tool library in Fusion with accurate tool offsets and stickouts for use by anyone in the SeattleU machine shop.
Squaring a vise
Vise was out of square, so spent some time learning how to stone the table and re-square a vise. Ensured vise was square to ±0.0001". Very satisfying when you get it just right!
Microscope Stage
Spent a long time learning how to setup stock, align WCS, learn the different kinds of 2D and 3D toolpaths, axial depth of cut, radial, feeds and speeds, and the other important CNC variables.
First project was to model and machine a custom microscope stage for the SeattleU physics department.
Finished Part
Some chatter from a 1/4" with too much stickout, but otherwise pretty good surface finish for no coolant.
Desk Tray
Designed a desk tray meant to hold keys, earbuds, and other loose items on your desk with the goal to have a nice weight and shape to stay planted on your desk. G2 curvature fillets and a hemispherical cutout for items to fall to the center. Small bores on bottom to place rubber feet in. Had to learn how to use a ball endmill and program a 3D parallel toolpath in Fusion.
Adaptive toolpath with fine stepdown before parallel toolpath to reduce chip load on ball
Flute Length
First try, the shank gouged the side some because I didn't realize the flute length wasn't long enough for the part depth. Fixed on the second attempt!
Final Part
Really happy with the result. Has a nice weight and feels very premium. A next step would be to bead blast and anodize. Gifted to my industrial designer dad for his birthday.
Coolant Adventure
When I started working with the Haas, it seems no one had ever used coolant in the machine. Along with some peers, we managed to get some coolant concentrate and I worked on cleaning the sump, setting up an oil skimmer, and mixing all the coolant with 10% concentration.
Messy? Yes. Worth it? Absolutely.
Also yes the refractometer says 4%, this was for a first mix to clear the system :-)
Next Steps
Very fortunate I get to be working with such amazing machines and resources, it's been my dream for a long time.
I am leading the manufacturing team of the Aerospace and Aviation Club, so we will be machining nozzles, motor casings, and any other components the team needs. We used to outsource all complex billet parts, and now we can do it in house.
Thank you for reading.
