It takes a lot of work to shave a softball bat with a lathe. You can view the details at the link below.
Shave a Baseball bat with a lathe
You weren't specific on the first post, so I answered the question you asked. Thank you for clarifying and being more specific now...
I am unable to find instructions on how to shave the inside of a softball bat or "juice" the bat. I will opt out of this question and give another expert the chance to find what you're looking for.
"Bat doctors may also use a lathe to shave the inside of a bat's barrel to make it springier, in effect giving the ball an extra boost on contact. "
"Disappointed with the performance of a new $500 bat, he hit the garage, removed the bat's end cap and examined its innards. "I'm a very diagnostic individual," he says. He had the barrel shaved down at a machine shop, and discovered it hit balls farther than an unmodified bat did"
This website suggests another way you can shave the bat:(http://www.bostonbaseball.com/whitesox/baseball_extras/physics.html )
" A lighter bat is easier to swing, especially a bat that's been lightened on the business end. But as we like to say in physics class, "it turns out that" one could get the very same very bearable lightness of bat by choking up about 1 inch (2.5 centimeters). Or, if you want to get tricky, just shave 0.1 inches off (3 box tops wrapped on the bat's worth) the diameter of a regular bat. This loss of diameter may be a problem for those who want to get out by hitting pop-ups. For the rest of us, it's the way to go, especially when it's time to sign your major-league bat maker's contract."
If that's not enough info, your best bet may be to purchase this ebook for $6 that claims to cover many different ways to juice your bat, including shavinghttp://cgi.ebay.com/DOCTOR-ENDLOAD-JUICE-SHAVE-ANY-SOFTBALL-BAT-HOW-TO_W0QQitemZ330121910774QQcmdZViewItem Since it's an ebook, you should be able to receive it very quickly. (there are other options on eBay as well)
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