I recently got my first shot at using a boring head in my mini mill. It worked, after a fashion but I have some questions.
I was trying to bore a flat bottomed recess for a large nut (Mini mill column nut to be exact.) and I was able to complete it but I chipped one carbide tipped boring bar and had a lot of chatter in the process.
I started by drilling a 1" through hole then set a depth stop and started by taking small passes further and further out by adjusting the dial on the boring head. After a few passes and getting progressively further out it would bore OK until I hit the bottom where it would chatter like a banshee.
So, specifically I am wondering what angle do you set the head of the boring bar in to the boring head at? I tried to keep it as parallel to the boring head travel as I could eyeball... is that right? Is there a better way than "That looks about straight"?
Finally... any tips for reducing the bottoming out chatter, or ideas what I was doing wrong in the first place? Maybe you aren't even supposed to flat bottom by boring in the first place?
Any other tips for boring operations?
I was trying to bore a flat bottomed recess for a large nut (Mini mill column nut to be exact.) and I was able to complete it but I chipped one carbide tipped boring bar and had a lot of chatter in the process.
I started by drilling a 1" through hole then set a depth stop and started by taking small passes further and further out by adjusting the dial on the boring head. After a few passes and getting progressively further out it would bore OK until I hit the bottom where it would chatter like a banshee.
So, specifically I am wondering what angle do you set the head of the boring bar in to the boring head at? I tried to keep it as parallel to the boring head travel as I could eyeball... is that right? Is there a better way than "That looks about straight"?
Finally... any tips for reducing the bottoming out chatter, or ideas what I was doing wrong in the first place? Maybe you aren't even supposed to flat bottom by boring in the first place?
Any other tips for boring operations?