Hi all. I needed to replace some rusted thin steels brackets on my outdoor sauna with something nicer. I need 16 of them so cutting them by hand would be painful without a vertical bandsaw.
I have a CNC and some aluminum leftovers so makes sense to use that
It is not a precision operation, so my workflow was the following:
- take a photo on top of grid paper
- import to FreeCAD
- roughly sketch around
- 3d print a sample and test fit
- export to dxf
- import into PureCutCNC and create toolpath in there
Cutting parameters: 3mm single flute, trochoidal with 10% advance per step, full depth of cut, 1 on the router for speed, feed set to 2500 but acceleration limited to around 800 mm/min actual speed in the cut. Material is 3mm aluminum checker plate.
The endmill had seen better days even before I’ve started so I was doing an air blast by holding a air nozzle by hand. Cuts surprisingly well. machine is full size LR4
finishing pass at full depth at 600mm/min. parts came out ±0.1mm
I’ve tried to do everything with a single tool. Helical boring 3.5mm holes then roughing then finishing but end up doing it in two operations. Drill or bore first. then drive some screws in the holes to hold it better. the parts were vibrating to much from trochoidal motion.
I also switched from helical boring holes to drilling with a 3.5mm drill bit
Another observation is that everything is covered with aluminum chips. I was not running dust extraction to see what was happening and also helping with an air nozzle
the photos are before deburring. looks much nicer in the real life
