Reply To: Lionkev's Aluminum Attempts

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#39313

Kevin Lopez
Participant

I pretty much gave up plunging. I tried pecking .5mm at a time, and on the last depth, it went really nasty. Made this low rumble but the bit didn’t break. I will just half predrill the holes then finish them on my hand drill. No biggie there.

The test was done on a single flute. Only now I only have 1 left… A 3mm slot 9mm deep doesn’t allow for any chip evacuation at all. I will remedy this by doing the wider deeper cuts. Technically this wastes more material but at this point I just want to finish the part without something going really bad.

True about the rigidity, but my z is so short as it is I don’t think it will make a difference. There is a diminishing return line like I said. At one point all the flex is not the z axis turning, it is the linear flex of the rails, zip ties, etc.

I got teased into my success lol. I think my cam was great for thin parts but I got to change it up now that I am trying to go all the way through 3/8″. The further the bit goes into aluminum the more scared I get cause it’s hell down there D:

Still trying to fix the awkward chatter points. Picture a circular cut, the bit chatters at 12 o clock and 6 o clock. At 3 and 9, there is no chatter at all and the harmonics are great. I tried to test if it was the fact that my x axis conduit was twice as long by test cutting at the very corner of my machine. No luck. 🙁 This is by far the problem I am concerned with the most. It’s weird because even on light finish passes, at 12 and 6, this low rumble occurs. It get’s so bad you can actually see the bit vibrating back and forth. Yikes. I tried taking off my shims and it had no effect. I am able to run really aggressive settings with no chatter except when it hits 12 and 6. I don’t get this at all…

I am going to keep testing and trying until finally I get a finished part. 🙂