Hi So far I have limited my aluminum milling to very exposed profiles (basically shaving of some material on the outside of the stock) and small pockets. My Z-axis upgrade projects requires me to machine one plate that has a bit of an interesting shape and I would like to get some suggestions on how to do it (See attached pic). I'll be using 1/4" 6061 on a 1x1m Sphinx. 1. Choice of endmill Either 1/4 vs 1/8. Conventional wisdom would suggest 1/4. However, 1/8 allows me to run the tool at lower feedrates. 1/8 also removes less material which should correspond to smaller cutting forces on the machine (?) 2. How to cut the profiles. I see three options here. Traditional slotting with ramping and max 1-2mm depth of cut, roughing + finishing pass. Use adaptive clearing to rough out everything and run finishing pass. Use adaptive clearing to rough out a slot larger then the cutter outside the finishing pass. It seems that John Saunders at NYCNC is not a fan of slotting. (). I'm also partial to the adaptive toolpaths in Fusion360 since it allows some degree of control of the cutting forces. Anyhoo, how would you go about cutting this profile?
If I was doing this, here is what I would do if I wanted a really clean looking part. Using a 1/8" endmill, I would do the following: 1) Machine all holes in the plate first. For the biggest hole you should do a 2d pocket to remove all material. You should do that pocket leaving radial stock. Then follow up with a finishing pass. 2) Utilizing the holes you just machined, sink some screws into your waste board, and 2d contour the profile, leaving stock. Then perform a finishing pass. Here are some feed's and speeds that I have had success with using a 1/8" endmill. 24000 RPM - 635mm/min - .5mm doc - Roughing Pass, then I would go 1mm finishing pass and slow down to 300mm/min.
