Checked the arbor in a collet and it clears with about 1/4" to spare. Turns out that in the B&S7 collets I have, the collet grip length is almost the length of the shank, which is good for grip.
Steve
Boring head arbor
Re: Boring head arbor
These have an interesting mechanism.
Instead of your usual screw that moves the boring bit sideways, the large collar is internally threaded.
The bar that is the second piece from the right is threaded on the ends and fits in the groove of the main body (on the left).
The part that holds the boring bar has a diagonal groove in it, and when the collar is turned, the bar moves up/down and that causes the boring bar holder to move side to side.
The lock has an interesting feature. When you tighten the screw, it pushes up on two pins. Those pins have ramps on the side that force a thing that looks like a snap ring out. As the snap rings diameter gets larger, it locks into the recess in the large collar (you can see the recess in the picture). This ensures that when you lock it, it does not change the position of the boring head.
Steve
The bar that is the second piece from the right is threaded on the ends and fits in the groove of the main body (on the left).
The part that holds the boring bar has a diagonal groove in it, and when the collar is turned, the bar moves up/down and that causes the boring bar holder to move side to side.
The lock has an interesting feature. When you tighten the screw, it pushes up on two pins. Those pins have ramps on the side that force a thing that looks like a snap ring out. As the snap rings diameter gets larger, it locks into the recess in the large collar (you can see the recess in the picture). This ensures that when you lock it, it does not change the position of the boring head.
Steve
Re: Boring head arbor
Wow Steve, thanks. I was wondering about these. This is certainly a keeper of a head and your post.