Boring bar chatter

[RaisedByWolves]

Are you absolutely sure you are on center with the boring bar? Try going a little above center to be sure the bar is cutting and not rubbing the side of the insert. Take very light passes with faster feed. Maybe 0.005" per side @ 0.010" per rev feed.

Being "On" center is the last thing you want.

I go by eye, but I usually go.....well....it depends on the diameter of the bore really.

On a 1" bore I might set the tool .020 higher than on center, maybe more and even higher on a larger diameter.

You want to take heel rubbing into account, but a larger component is flex. The bar is going to flex, so putting it above center and truning the cutting tip downwards will make the cut push the bar away from the cut and in this limit up/down vibrations.

You basically want it pushed into a position where it can no longer vibrate.

 

[Wino1442]

Thank you all for your suggestions....I haven't had a chance to try any of them (busy with the family), but I will definitely give them and try and report back. Thanks again

 

[GrifterGuru]

Being "On" center is the last thing you want.

Aint that the truth! Being above centre is where it needs to be.

Also found the rake angle of the tool plays into that as well.

 

[Batmanacw]

Being "On" center is the last thing you want.

I go by eye, but I usually go.....well....it depends on the diameter of the bore really.

On a 1" bore I might set the tool .020 higher than on center, maybe more and even higher on a larger diameter.

You want to take heel rubbing into account, but a larger component is flex. The bar is going to flex, so putting it above center and truning the cutting tip downwards will make the cut push the bar away from the cut and in this limit up/down vibrations.

You basically want it pushed into a position where it can no longer vibrate.

So when I told him to go a little above center you are agreeing with me? Lol.

Most boring bars are already tipped for clearance. At least all mine are I think.

 

[GrifterGuru]

So when I told him to go a little above center you are agreeing with me? Lol.

Most boring bars are already tipped for clearance. At least all mine are I think.

A boring bar "on centre" will always be problematic. Above centre is more usual and the "proven" method.

 

[RaisedByWolves]

So when I told him to go a little above center you are agreeing with me? Lol.

Most boring bars are already tipped for clearance. At least all mine are I think.

Yes, wasn't calling you out, I just wanted to make sure things were clear for the OP.

Clearance is specific to the job and tooling at hand, there are no guarantees.