North Vernon, IN-based Injection Mold, Inc. is a full-service shop that specializes in rapid prototyping (RP) molds, which General Manager Jason Vawter describes as prototype tools built for customers that need plastic parts to test for fit and function. The company builds the prototype tool and molds the parts before building a full production tool. A desire to reduce set-up times and increase accuracy led the company to upgrade from three- to five-axis machines with the help of Hurco Companies, Inc. (Indianapolis, IN).
The company also produces injection molds and bridge tools—everything from simple prototypes to high-volume, hot runner production tools for multiple industries such as medical, electronics, safety, baby products, appliance and plumbing.
According to Vawter, the company has a stellar reputation when it comes to speed. “We have made a commitment to stay on top of technology,” Vawter says. “We have newer equipment—like high-speed machining centers and now five-axis capabilities—to shorten the time it takes to go from design to putting parts in our customers’ hands. This new technology allows us to be more efficient, which in turn means we can take on more work and also meet the short turnaround times our customers need.”
This need for speed led Injection Mold to consider upgrading from three-axis to five-axis technology. “A lot of our work involves multiple setups on three-axis machines, and with the short deliveries we do, we needed to find a way to speed up our times,” Vawter notes. “Using five-axis technology would allow us to eliminate a lot of set-ups.”
Vawter looked at a number of different machines, but all roads led to Hurco. “One of the reasons we went with Hurco is that they are right down the road from us,” he says. “We also owned Hurcos in the past and have been very happy with them. We found that the VMX30U was exactly what we were looking for.”
Three- to Five-Axis Transition
The VMX30U that Injection Mold purchased last year has X/Y/Z travels of 30x20x20.5 inches and rapids of 1,181 in X and Y, and 1,378 per minute in Z, notes Hurco Marketing Director Phil Fassnacht. Fassnacht says the mechanical team considered rigidity during each design decision. “We use larger linear rails that are mounted to a machined shoulder to increase rigidity,” he notes. “Additionally, the rails are wedge-locked to the frame to reduce vibration instead of simply being face milled. All of the Hurco five-axis trunnion style (U-Series) machines provide more clearance in the Z-axis because they have been designed with an integrated trunnion table instead of simply attaching a table on a three-axis machine. And, the mechanical design team added a four-inch riser on the Z-axis column.”
According to Fassnacht, Hurco decided to make five-axis a priority 10 years ago and has dedicated resources to the development of features that make the transition easy for three-axis shops like Injection Mold and others that are new to five-axis machining.”
Vawter notes that the Hurco control makes the five-sided process easier with features like Transform Plane and NC/Conversational Merge. “With Transform Plane, you just need to locate one part zero and the remaining part zero locations can be defined as incremental measurements from the original location,” he says. “ It basically changes programming on a five-axis mill back to 2.5D programming that you do on a three-axis mill. You don’t need to worry about the tilting and the rotating. The technology does the work for you so you can start making chips faster.”
Vawter sent one of his employees to the Hurco facility for training before having the machine installed on the shop floor. Then, a Hurco technician followed up with some additional on-the-floor training with Injection Mold employees. “Five-axis was a brand new area for us,” Vawter recalls. “Since we have always had three-axis, we grew accustomed to working in three planes. Then, all of a sudden, there were five.” While he says it took the employees several months to get completely comfortable with the machine, Hurco was always readily available to field questions.
Injection Mold bought the machine solely for the purpose of eliminating multiple set-ups, but Vawter notes the more they use the VMX30U, the more they find they can do with it. “For example, we had a four-cavity production tool with three slides per part, and they have angled holes through them on 20 degrees,” he elaborates. “There’s a 25-degree angle on the back with tapped holes. To machine these in the past, we would have a set-up for each operation on a manual mill. The way we would have done it would have taken probably five set-ups; and we probably would have an hour to an hour and a half on each block. When we do it on the VMX30U, it is one set-up and 20 minutes in each piece. We set-up our block of steel, it machines it from the top, then the machine rotates the table so we can machine the sides—which in a three-axis machine would require an addition set-up for each side. Then the machine will rotate 20 degree so we can drill the hole.”
Another payoff is higher accuracy. “Each time you have to take the piece out of the machine to put in another set-up, you take a chance of everything not blending out,” Vawter explains. “Now we just pick it up one time and we will cut from the top and the machine will rotate and cut the piece from the side—so accuracy is better. We maintain .005 micron accuracy on our work.”
Vawter is very pleased with the VMX30U. “Once we made the leap, we continue to find more benefits—things we didn’t even consider are now possible. We have had it a little over a year and we feel like we are just starting to scratch the surface of what we can utilize it for. We will definitely consider another five-axis purchase by year’s end.”
For More Information
Injection Mold, Inc. / (812) 346-7002
email@example.com / injectiomoldinc.com