I have to run a 1/16 endmill in 6061. I am using a air powered spindle to get to the 45000 rpm where carbide should be happy.
My question is should I use 2 or 4 flute. Will 4 flute have enough chip clearance for aluminum? Most cuts will be with about a 10 to 15% setover but there are a couple cuts that will be full width. Cut depth 1/16".
Two or three flute would be my choice
Might not like that 1 to 1 depth of cut full width.
At $5.00 per end mill I would try both.Maybe you can go faster with 4 flute?
I think a 4 flute will last about 30 seconds if you're lucky. At 45,000 rpm the chips will clog the flutes no matter what kind of coolant you're running. I would def use a 2 flute.
I think I will go with the 2 flute then. I did a test with a 2 flute at about 5k rpm (The max of my mill). At that speed it took almost 4.5 hours to finish the job! Ouch! At a whopping 2ipm!
Hopefully this spindle will do the trick. Seems powerful enough to spin a 1/16" bit. Even if it bogs down to 30k or so it will still be 6 times faster than my normal spindle. Hopefully the new collet will show up tomorrow so I can give it a try. I still have a couple 2 flutes to break.. err... try!
What should I do for coolant? I was using compressed air with a bit of mist to keep the aluminum dust down.
Go with a 3 flute, Zirconium coated EM.
I use Accupro brand every day, all day long.
1/8" at 24,000 rpm, 1/4" deep, full width, 70 IPM
Plunge in a 70 IPM. I don't even remember changing that tool for quite a few weeks by now.
The Zirconium coating works really good, wear is not an issue. And I haven't seen onne ever gum up yet.
Using Rustlick 375R coolant, 6% on the brix scale.
(oops! this is for 1/8" Endmill. You are using 1/16" ... Maybe a 2 flute at that size, to get the gullet clearance. )
45,000 rpm will be awesome. I'd start out around 140 IPM considering your DOC. Go up from there, maybe towards 200 IPM, and beyond.
Tool life should be a function of rigidity of the machine. You might not change that tool for a few months if you have a rigid setup/low runout/balanced setup.
140 ipm!!!! I can barely rapid that fast! ME Consultant was giving me something like ~20 ipm full depth and full width.
Well see if this spindle works or not. Seems like it has decent power at rated rpm. Rated at 65000 rpm at 14 cfm. Designed for jig-grinding. For what I paid its worth a try. If not I will look into a spindle multiplier.
Be sure to let us know what you wind up with.
OK, I got the collet for the vulcanaire. I was able to run 1/32" endmill at full width .01 deep at 30 ipm. No noticeable slowdown of the spindle. Ran a 3/32" 3 flute at 20 ipm. Any more and the spindle will bog down and stop if I let it. The two 1/16" were either dull or I didnt have enough coolant going and now I have two more potential scribe tips!
It does suck the air though! This is my compressor:
5HP @ 14.7CFM Oilless It keeps up with it. This should work for now until I can come up with a more permanent option. Pic of my setup below.
I think that option is going to be in the last pic at the bottom. Its a spindle out of a ATI PCB router. Designed to run somewhere around 25krpm. Uses 2VB collets and it is set up to blast air down the spindle to clear out any dust. I spun it up with air and its still pretty quiet. While holding it there is no vibration at all.
I will mount it with its collet release cylinder on a plate and attach it to a quill bracket I got from Tormach. I think I can use a jackshaft to take off from the mill's spindle and get it up to speed that way. This will save a whole lot of power. Running a 3hp motor vs a 5HP! And noise too.