Hi Bill,
Do you cut-off and re-point in this case or actually grind cutting edges to salvage the tool? How do you do it in your shop?
Thanks for all your great input to the forum. You’re helping more people than you know!
Jace
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Jace, thank you so much for your very kind comments! Just glad to be able to help where I can.
I don’t actually attempt to recondition or regrind my cutters because they’re only 1/8", and it wouldn’t work well. That said, it might be possible to regrind the tip on a 2-flute end mill by hand on a bench grinder. It wouldn’t be real great, but probably good enough to use for awhile. And most of my cutters are carbide, which requires a special “green” wheel on a bench grinder, or a diamond wheel.
When I was running a machine for a living, I used to on occasion regrind the tips on 2 & 4 flute end mills that were large enough to allow doing so. It was never perfect, but often it was just enough to allow a fresh life for plunge cutting. I wouldn’t attempt to grind the length of the flutes by hand, only the tips which usually wear out the quickest.
Good old days, circa 1989 in one of the many Detroit area shops I worked in.
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Awesome pics, Bill! That’s a lot of great experience you have under your belt!
I’ve had Vortex Tool cut-off and re-point solid carbide bits for me with decent success. They offer a sharpening service and service any brand of tool. That was done for production work on a DMS 4’x8’ Patriot to try to save on tooling cost. We would wait until we had about 10 dull tools and ship them all back to have them re-pointed for about 1/2-3/4 the cost of a new tool depending on the initial cost. With these DOCs that are common for milling Aluminum on the Onefinity, you could get a lot of life out of one tool using this service (worth mentioning that I have zero affiliation to them, just wanted to share for anyone interested).
They also have a nice chip load chart, but as you said above, the aluminum estimates are probably too aggressive for the 1F. That seems to be the anecdotal evidence anyway from all these tests various users have ran.
Hey Jace,
The Onefinity can definitely handle higher chip loads… this was just a brief test with a 1/4in endmill @ 0.004in, we also tried it at ~0.006in.
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I saw this! Super awesome video. I guess I hadn’t paid much attention to what chip load you were at in this case. Looking more closely at this video, it seems like you get almost completely around each triangle at your z/plunge feed rate while ramping in, then it kicks up to your x/y feed. That’s got an impact on chip load for sure. What’s are your feeds in x/y vs z?
Thanks, that one was done at 80ipm, and ramping down at 40ipm… I think.
We’ve been messing around with the F/S so much I can’t really remember. 
When you say “That’s got an impact on chip load for sure” do you mean like the chip load would spike?
As for the corners, that was before I learned about the +10% rule of you cutter radius lol…always learning something new!
Yeah, sort of. There’s definitely a step function in your feed rate with this tool path. Could be nice to smooth out that transition somehow. In this case, your (theoretical) chip load at 40 ipm is half of what it is at 80 ipm while holding the other variables constant. So, if you’re ramping in at a low angle, moving primarily in x/y and only marginally in z, your effective chip load is .002" instead of your expected .004" @ 80 ipm. For the record, I think this is still a decent approach for entering the material and likely part of why these cuts were so successful, along with that nice stubby/stout bit and a hollow part. I’m not an expert on machining aluminum, so don’t take my thoughts too seriously! Looking forward to gaining more hands-on experience with 6061-T6 once my 1F arrives in a couple weeks.
I think my ramping distance is quite short, and that’s why the change is so abrupt.
Definitely, we tried a 1/8in bit and encountered a lot of tool-rigidity and chip evacuation issues. Cutting this hollow tubing is really nice and easy to cut - no chip clogging and no coolant/oil needed.
I’m in the same boat as you, but it’s always nice to have somebody point out the things that could be improved. Thank you for your suggestions! Post up your progress once you are all set up and dialed in - would love to see how you are going about cutting aluminum!
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