New U-Build Machine & Power Tools Catalog

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From the "Machinists" section of www.poormanspubs.us:
"Boring bars provide a superior way to make round holes with true parallel walls, especially when mounted between centers."
Now I'm just a newbie, a babe-in-the-woods when it comes to machining, so can somebody explain how you use a boring bar _between centers_?? The only way that I can think of is to leave an island in the middle of the bored hole, for the tail stock center. Then clean out the island in a chuck. Do people really do that?
Bob
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Bob Engelhardt wrote:

Thanks for all the enlightenment. When I posted, I really thought that the quote was a mistake. Learn something everyday, hopefully.
But, about this turning between centers. I guess that you have some of the same problems as you have boring in a chuck. Particularly with long, narrow bores. In a chuck, the bar deflects and between centers the bar springs. Probably not as much as with a bar. Between centers the maximum length of the bore is 1/2 the distance between centers. In a chuck you can remove the tailstock and get a deeper bore.
About this problem of bar deflecting or springing: do they ever use an _internal_ follow rest? I.e., one mounted to the bar and bearing on the bore? It seems like that would be "just the ticket" for really long bores.
Bob
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