Whining End Mill

I can only surmise that either that rougher is bigger than your mill can handle or it is not being held rigidly enough. Do you have an ER-40 chuck that you can try it with?
 
ddickey said:
So roughing or corn cob end mills are used for side milling and end mills are used for either. Is there a specific roughing type end mill made fir end milling?
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I would use a ordinary two flute end mill.
 
I would test the rigidity of the tool and collet mounting, first by just wiggling the end mill. Tool could also be indicated and wiggled, not yanked, looking for runout. Niagara makes very good end mills, some of the finest available. You may have damaged it by not using a deep enough feed, and rubbing dulled the cutting edges. Just guessing on all of this, each test is worth many expert (or not so expert) opinions...
 
I'll try a 2 flute tonight. I have an R8-ER32 but not a 40.
.75" wavy end mill. Starts at .100" DOC and end up at .200" DOC
 
Those two videos tell a story. If that is the same end mill then I would be taking a hard look at the endmill holder. The endmill holder has a lot more stick out than the collet so that is a factor. But does the holder fit the spindle taper properly? Is the holder bore oversize? Are the spindle bearings right on the edge of being loose? I have some cheaper holders and they tend to have more chatter than my collet holders.

Try less width of cut, maybe 40% or so of the endmill diameter. I find that the depth of cut makes a big difference in chatter. I did a cut a while back that at one diameter deep did not chatter, and at two diameters deep the chatter was unacceptable. Changing feed and speed made no difference. Also for the most part, I try to use an endmill that has a length of cut that is just over the depth that I need to cut, keeps everything as short as possible.
 
Good question on the holder. The 1" is cheap Asian but the .75" is a quality Taiwan made holder.
 
ddickey said:
Tried a piece of aluminum 7075 i think it was.
.100" DOC 750 rpm and also 350 rpm same sound.
According to Tom these are for side milling so will hang onto it for those jobs but will probably not use it for anything else.
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4 flute rougher on Aluminum ? It's going to load up on you quickly ! 2 flute for aluminum and keep it lubricated . I was using a 1" corn cob last night going thru 15-5 ss 32RC . Cut it like butter . ( on a full size mill )
 
What mill do you have? How did you hold the end mill?
 
If you're using a 1" endmill on an R8 machine, that means one of those uber-stickout 1" endmill holders where all of the endmill will be outside of the spindle. I'd stick to a 1/2" rougher and you'll be fine. Why do you need to run a 1" end mill? You're not going to be able to use it's potential on a Bridgeport type machine. I have several different roughers for my 6x26 - 3fl coarse for aluminium and 4fl fine for steel. They work fabulously, especially the 1/2 3fl coarse in aluminium, that just plows through material.
 
Why, simply because I had one.
I didn't realize R8 spindle wouldn't be rigid enough.
 
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