A milling bench vise is a must-have piece of equipment for any machine shop. Which vise to choose depends on whether the shop is a personal hobby shop or a professional operation. The difference in price ranges from $40 to $5,000. Obviously, there is a potential to misspend a lot of money.
How often the milling bench vise will be used is the first piece of information that needs to be determined. Is this something that will be used every day or once a week? Something that is used every day will have to be sturdier than something only used occasionally. The heavy duty use of bench vise would require a cast steel construction. Not all metals are forged equal. The softer metal would be acceptable for infrequent use but I will not be a good investment of money for a milling bench vise under heavy use.
A swivel base or a fixed base bench vise is also determined by usage. A swivel base allows for 360 degree swiveling on a horizontal plane. This is very convenient for small jobs, but you should not use it for rough or heavy work because it is less stable than a fixed base bench vise. The swivel base can be removed in most cases making the bench vise both a fixed base and a swivel base as needed.
A universal bench vise tilts 90 degree on the vertical plain and 360 degree on the horizontal plain and this is the most versatile vise for milling at all angles.
An air or hydraulic bench vise is wonderful for high production shops. They quickly grip or release the object being worked. They have a consistent pressure to help prevent marring of the work surface. The manual bench vise have a lever that is turned by hand. It is tempting to bang the handle with a mallet to make sure it is tight, but this will likely mar the work and damage the threads on the bench vise.
Finally, try to determine how large the work being milled will be. Most of the bench vise only have up to 4 inch jaw openings. The larger industrial milling bench vise have up to 8 inch jaw openings.
A good quality one will have precise dimensions for perfect alignments. Remember that much time and energy can be spent while trying to buy a good bench vise that needs to be grinded into shape. It is more than a tool and it is an investment. A cheap, poorly made, or unstable bench vise can cause damage to the work and the machine and also to the operator. To make a safe decision, you should read bench vise reviews.