End Mill Chatter?

New Home Forum Getting Started End Mill Chatter?

This topic contains 3 replies, has 3 voices, and was last updated by Profile photo of Fermata Fermata 2 weeks, 2 days ago.

Viewing 4 posts - 1 through 4 (of 4 total)
  • Author
    Posts
  • #21342
    Profile photo of Mike B
    Mike B
    Participant

    I was doing my first cut with the MPCNC

    so I was using a 1/4″ double flute end mill on plywood

    I had a couple spots when the bit was travelling at about a 45 degree angle across the x and y axis
    that resulted in some chatter of the end mill.

    What is chattering generally an indication of?

    the rest of the cutting was very smooth, no burnt spots, didn’t hear the spindle bog at all.
    the “saw dust” was very fine… not sure if this is good or bad?

    I’m using a 1.5kw spindle… spindle speed was 28,000 rpms

    x/y rate was 12mm/s

    #21345
    Profile photo of vicious1
    vicious1
    Keymaster

    Tough to say could be anything, loose tool/gantry/machine flex, or bad tool path

    The easiest thing to try is spindle speed, if you get a poor cut heavy vibration bad dimensions it is usually too slow, too fast and you can get burning of the wood.

    Powder usually means too fast, you want shreds, or small chips. Powder means you are recutting your chips because they can’t get out of the way of the bit as it comes back around so they get cut several times, giving a poor cut quality because your tool is working harder than it should. high spindle speeeds are best with a single flute if you can’t turn your speeds down. 1 cut per revolution is half the speed of 2 cuts per revolution.

    #21347
    Profile photo of Mike B
    Mike B
    Participant

    tool is securely fastened…gantry all seems to be tight..

    tool path was generated by estlcam .. not too sure of ways to change this.

    interesting… alright I may run it again and try lowering the speed to see how it changes things.

    thanks for your time it’s appreciated.

    #21359
    Profile photo of Fermata
    Fermata
    Participant

    I think the problem is like @vicious1 says, slow it down. remember X and Y are speed max in those direction, so if you are going at a 45 degree angle, you are going max in both, so thats 12mm/s * 1.41. (which is Square root of 2)….

Viewing 4 posts - 1 through 4 (of 4 total)

You must be logged in to reply to this topic.