Using Machine Vises In Your Shop Or Business
A vise is a common workshop tool used primarily to steady an object so it may be worked upon with other tools and devices. Standard equipment in any wood or metal working facility includes bench and tower vises, angle vises, drill presses as well as a wide variety of clamps and braces intended to make drilling, sanding, polishing and other processes easier to accomplish. While the basic principles of use apply to both woodworking and metal machining, the equipment can be very different and with regard to milling machine vises, often more complex.
When performing mill work a machinist must adhere to strict production guidelines that leave little tolerance for product variation. To achieve uniformity in quality and workmanship careful attention to set-up and calibration is required before any manufacturing can begin. This will include properly adjusting machine vises to prepare material for alteration.
Depending on the work to perform a machine vise can be a simple bench top model. Most of these are comprised of three parts: the fixed jaw, movable jaw and the screw. The fixed jaw stays in place while the screw adjusts the movable jaw. When using this type of vise you must first ensure the entire vise is securely fastened to the bench or table surface. Check any hardware responsible for preventing the vise from moving or vibrating. Loose hardware in this area may allow the material you will be working with to move even if it is securely clamped in the milling machine vise.
Many precision machine vises use interchangeable jaws to accommodate different tolerances for stress, scratching and grip. Some jaws have a rough textured face that resists slipping. Others are highly polished and smooth or “soft” to prevent abrasion to the surface of metal components. A machinist must pay attention to specs and utilize the appropriate jaws. The surfaces of any additional blocks or clamps that will be in contact with the product must be taken into account as well.
Unlike a typical wood vise, a machining vise can have several contact points where the metal product will be in contact, and under pressure, with the vise itself. The entire area should be clean and free of debris but special attention is required at these contact points. It is common for machinists to work with tolerances measured in thousandths of an inch. Dust, wood splinters or tiny fragments of metal can offset the calibration of the vise and result in an unsatisfactory finished product. Keeping the vise and surrounding area clean helps prevent costly errors.
Newer machining equipment uses computerized gauges to aid in set-up procedures and cut back on machine downtime. Even so, a machinist still must have a working knowledge of calibration tools. Careful reading of blueprints and diagrams, as well as the gauges themselves, is critical to a final product being within tolerance. Keep all instruments clean and in optimal condition. Specialized vises that rotate or are designed to hold parts at angles may have to be calibrated and adjusted to specifications before any work can be performed.
After securing a part within a vise, ensure the part is has not moved or warped under the pressure of the clamps or jaws. If the material is to be flat after clamping check for unintended rising or sliding that can occur if too much jaw pressure is applied. This is especially important with “soft” materials that may become defective when clamped too tightly. Remember to only use enough pressure to secure the material for alteration.
There are many types of metal shop vises. Many will have their own unique procedures that will be learned through proper training and experience. Whichever vise design a machinist must use incorporating neatness, organization, focus, proper instrumentation and patience into preparing the vise for production is paramount to achieving satisfactory results.