Here's the toolpath in Fusion CAM. Fatboy here fancies using the 8mm end mill to drill out the 9mm bores for the fixing bolts. More sensible punters would opt for a 9mm drill. More about this later...
In the CNC12 controls, the gcode is loaded and ready to go.
That seems to be going OK, although the ramp feedrate is abysmally slow. Can't be arsed to rerun the toolpaths, though.
It doesn't sound happy with the grievously slow ramp. It's in danger of rubbing rather than cutting - the last thing you want when machining stainless steel, since this is liable to cause work hardening. You really need to go big or go home but yesterday I wimped out and cut the feeds and speeds by the best part of 50%. Furthermore, cutting a slot using a profile toolpath with 100% optimal(?) load possibly isn't clever. An adaptive toolpath might have been a bit more obvious and sensible.
But it seems to be coping ok so far....
By this point, the bores and bolt holes are done. The bolt holes were probably a stupid thing to do - using an 8mm end mill to bore a 9mm hole leaves very little room for chip evacuation. After the first couple of holes, the swarf changed from nice clean ribbons to something more like filings. I think I had damaged the tool before finishing those bolt holes.
Next (last) is the profile operation. This should ramp down progressively as the tool runs around the outer profile. The stepdown was a rather girlie 2mm or so per pass (from memory). That's barely using the tool - and I've almost certainly buggered the tool by this stage.
On the second pass, by which time tool was cutting at its "full" depth of 2mm, there was a loud click and a change in the sound of the tool cutting. And instead of cutting chips, it was trying its hand at stir welding.
So that's the end of that (rather expensive) tool. On the upside, the machined bores are a nice fit to the tube.
So without further CNC carnage, I'll simply flash up the bandsaw and liberate the flange.
With some angle grinder and belt sander action, I've recovered the flange from the stock.
That doesn't look too bad, although perhaps 7-8mm thick stock would have been a better choice.
The 32mm tube is a nice snug fit.
Looks like a reasonable result if you overlook the fucked up end mill.
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