Ball Mill

Not based on the information you give.

It is difficult for anyone to tell you based on information you gave. Please refer the Instruction Mannual by manufacturer of the ball mill for the whole process. If you don't have, ask them.

It's all about shake, rattle, and roll. Get Elvis to do it.

Use a surveyor's level, a laser, a level, and/or a clear water hose to get the four corners pretty close to the same elevation. According to weight, put proportionate rubbers or springs thereunder. (Or if zero, bolt them down tightly.)

(That's all facetious to some degree, but not necessarily to every degree.)

Better yet, consult the manufacturer's recommendations, such as don't mount it upside-down.

If you're asking, you should only be doing so if you're an observer to the process and looking for background information rather than being assigned to perform the task.

Large equipment such as ball mills can be quite deceptive. The tolerances for alignment are very tight. Straying from these figures can easily result in excessive vibration, bearing damage, broken gear teeth and ultimately, huge costs resulting from production interuption and repair costs.

A job like this should not be left in the hands of the uninitiated. If this is your position, suck it up, admit to the Owner that you don't know what you're doing and help him find somebody that does. Then, glue yourself to the Expert and start learning by example.