Quick-Change Vise Jaws System
Quick-change workholding systems can provide a great opportunity to increase production while allowing relatively quick recovery of the cost.
When a machine is making parts, it is making money. When it’s sitting idle, for whatever reason, it’s costing money. Shops need to be aware of the percentage of time their machines are producing, and they need to be on a constant lookout for ways to improve those percentages.
Improvement can come in many forms. Processes and personnel can have a significant impact on production times. Equipment can as well, but new equipment comes at a cost. So shops need to make educated decisions about how much such investments will help the bottom line. Quick-change workholding systems provide a great opportunity to increase production while allowing relatively quick recovery of the cost.
The Carvesmart quick-change vise jaw system, from Bellatex Industries, is designed for production and toolroom applications to replace the conventional method of attaching vise jaws to a vise using face mounted cap screws. This system employs three channeled clamping elements (from the top) and a dovetailed jaw design to couple the master jaw and soft or hard jaws. Carvesmart is designed to reduce setup time and improve setup reliability and quality. The dovetailed aluminum extruded barstock makes the soft jaw an inexpensive cut-to-length tool that can be reused or quickly recut with each part run. The system is a good fit for shops running repeating and tight tolerance work.
Located in a vise’s sweet spot, face-mounted cap screws can be problematic. They extend into the workholding zone, forcing work to be held in front of or above the cap screws. The Carvesmart dovetailed jaw provides a larger machinable workholding zone that permits holding parts deeper and more securely into the vise jaws. This design provides less jaw lift and more secure clamping, according to the company.
Using a T-handled hex wrench, the operator can quickly load the soft jaws from the front or side, loosening three channeled clamping elements from the top of each master jaw. Because the clamping mechanism is designed into the top, the vise does not need to be opened to allow access to the cap screws. Differential screws pull the channeled clamps, providing downward pressure to secure a jaw in place. The entire change-over takes between 40 and 60 seconds. When setting up an eight-station quad with 16 jaws, all of the jaws can be replaced in less than 12 minutes.
When reinstalling once carved jaws into the original master jaw and a vise that has not moved, and using a straight edge or side stop, repeatability should be within 0.001 inch. Alternatively, the original precut program and a resident tool can be used to recut the original female forms in new jaws. That quad can be in service in 30 minutes, versus a half day, and each station will be as accurate as on the first run.
Extruded aluminum soft jaw blanks are available in a variety of sizes. Small parts can use jaws as short as 1 inch of Carvesmart extruded barstock. Therefore, with a minimal amount of jaw material, four 1-inch jaws mounted into a 6-inch vise can hold two small parts.
The company offers economical dovetailed extruded aluminum for soft jaws in widths of ¾ inch by 2 inches, 1 inch by 2.25 inches and 2 inches by 3 inches, and lengths of 6 inches, 31 inches and 94 inches. Also available is ¾-inch by 2-inch dovetailed 1018 steel barstock in 6-inch and 31-inch lengths. Only one saw cut is necessary for any length from 1 inch to 94 inches, reducing jaw cost by half or more compared with purchasing a commercially made jaw or making them in-house. Not needing to organize, store, find, clean, reinstall, indicate in and offset used carved jaws yields additional savings.
“The Carvesmart jaw system is fast and secure,” says Andy Melde, senior R&D model shop machinist at a Minnesota medical device company. “The extruded jaw material allows me to cut jaws to any length as I need them. I have cut them as short as 1 inch and as long as 24 inches.”
Designed for toolroom and single-station vises, for reusing pre-carved jaws, hard jaws or working above the top of the vise, the Carvesmart #10000 6-inch tool steel master jaw set is ground flat and parallel within 0.0002 inch. The set includes two master jaws, a T-wrench and four ½ inch-13 low head cap screws.
Best suited for carved jaw and production work, the No. 20000 6-inch 6061 hard-coated aluminum master jaw set is machined flat and parallel within 0.002 inch. It incorporates threaded stainless steel inserts pressed into the master jaw from the bottom for the clamp screws. Two master jaws, a T-wrench and ½-inch-13 low head cap screws are included in each set.
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