Problems with boring on a lathe.

[mikey]

I don't see how setting a boring bar at an angle makes it stiffer. If anything it increases the stickout needed to make the cut.

James Harvey, in his book Machine Shop Trade Secrets, mentions that it does but does not substantiate it in any way. Angling the bar does reduce radial forces, with a max of 15 degrees of bar angle being the recommended limit. This will not significantly increase stickout.

On the other hand, if excessive radial forces is a problem then using a smaller nose radius and the appropriate depth of cut is probably a better approach.

 

[Syaminab]

James Harvey, in his book Machine Shop Trade Secrets, mentions that it does but does not substantiate it in any way. Angling the bar does reduce radial forces, with a max of 15 degrees of bar angle being the recommended limit. This will not significantly increase stickout.

On the other hand, if excessive radial forces is a problem then using a smaller nose radius and the appropriate depth of cut is probably a better approach.

Easy task to prove, grab a stick, push it sideways on your skin, hurts?...now poke with it at 90, sure hurts. Your somehow increasing stiffness by applying forces from a flying beam, to a column. All this of course, with its force components according with the angle. For me, it works straight against chatter on very hard material, where I need to sink the bar so it cuts deep enough to leave a nice finish.

regards.