Dui, ni shuo de dui
Ok, so I finally got the 3040 CNC running and made my first tests.
So far, here is my opinion:
The 3040 is way more forgiving than the MPCNC. For some reason I’m still unable to identify, I still have quite a lot of chattering. I’m pretty sure now it is not coming from my drill bits, since they are brand new and designed for aluminum milling. So I suspect it could be the aluminum itself not being of an appropriate grade, or maybe my spindle running too slow. I hope it is not the spindle speed, since I just bought it and it was quite expensive, that would really be annoying. It is advertised at 12 000 rpm, hope this is enough…
But, despite the heavy chattering, I did not have one single failed attempt, and all jobs ended up completed. That would have been impossible with the MPCNC, it would have just given up due to step losses.
So, that’s a very good point for the 3040 here.
I tried a few bits:
-Single flute: horrible results, crazy chattering, I was afraid the whole thing would explode
-dual flute: great result, not perfect though
-3 flutes: similar to dual flute, but a bit more chattering, so dual flute remained the best.
I’ve only used trochoidal milling so far, at 3 to 3.5 mm per pass for the aluminum, 10mm/s to 20mm/s, and 4% to 10% trochoidal step. Seemed to work equally fine at any of those speed intervals. Maybe the best results were at 4% step and 15mm/s, but the difference was marginal.
So, globally, I’m not satisfied with how the milling goes so far, still way too much noise and chatter, but at least it goes through and the end result after the finishing pass it ok.
I do not consider this as a real test, since I still don’t have a decent working setup, but at least I can attest that, for sure, the 3040 gives more room for error without sacrificing a lot of stock material.
I’ve made 2 parts with it, a bracket for my future computer case, and a bit lenght probe sensor. I finally managed to get the probe to work, no idea why it wasn’t working before…
Now everything is working, so the next step will be to purchase some good quality aluminum and see if this makes any difference.