CJS Millwork is a large custom millwork shop in Stamford, CT, with a reputation for being able to figure out how to make even the most difficult custom millwork pieces; smooth radiuses along curved edges, intricate pocketed table tops, lattice work with 3D perspectives, etc. Business has been robust especially when it involves designers, architects, and builders who want to add a special touch to their projects. However, robust does not always translate into profitable when it comes to producing special order millwork.
In 2011, the company began looking for more advanced software for programming its Komo VR 512, 3-axis CNC router with a 5’ x 12’ table in order to reduce the cost and lead times for intricate millwork pieces. CJS was very happy with this machine’s performance, but the company was interested in being able to automatically generate more advanced programs, particularly for the solid modeling of profiles on radius parts.
This had not been feasible in the past because of the complexity of manual programming involved. Instead, this of type of work was done with a shaper, which re-quired creating templates for each radius cut and purchasing an expensive knife to match the profile of the radius molding. Using the shaper was a cost-effective approach if the customer required 50 or more pieces. However, for smaller quantities, the time and cost of using the shaper significantly increased lead times and reduced profit margins on the type of work.
Ax the Knife
After surveying the marketplace, CJS invited two vendors to demo their CAM (Computer Aided Manufacturing) software, having them program complex test pieces similar to the ones CJS manufactures routinely. Mastercam X6 Router (from CNC Software, Inc., Tolland, CT) was chosen because its automated Swept 2D toolpath was ideally suited for projecting full profiles along a radius using a small standard cutting tool. Mastercam was also less expensive, because the software is divided into modules that CJS could purchase as needed.
Programmer Steve Scenna Jr. said, “This blew the whole thing wide open. First, we didn’t have to buy a $200 or $300 dollar knife every time we wanted to cut a profile. More important, instead of spending days making templates, we were spending just hours writing programs for our CNC Router.”
CJS continues to use the shaper for volume work or projects where templates al-ready exist. But now a customer can come in with a sample of something they would like made out of solid oak and CJS can model it in AutoCAD, import it into Mastercam, and match the requested item profitably, even if it's a quantity of one.
CJS purchased a Maintenance license of Mastercam, which entitled the company to training, free software upgrades, and technical support from their Reseller as needed. Scenna was soon using Mastercam every day, learning more and more things he could use it for. This learning process is on-going and continues to add value to the CAM programming software. In addition to Swept 2D, programming features he uses continually include:
Simulation: Backplot shows tool movement and Verify provides color-coded si-mulation of stock removal—so once a program has been sent out to the machine, Steve is confident that it will be manufactured correctly.
Toolpath Ramping allows toolpaths to be executed in pre-defined small incre-ments, which makes it easy to take small passes over fragile materials and reduce the potential for them becoming chipped or nicked.
Toolpath Trimming: Scenna can assign a toolpath to an entire workpiece and then select areas of the part that he wants to “trim” so that the cutter will avoid these areas. This approach can save hours of programming time compared to an approach where the toolpath must be created for every area of the part to which it is to be applied.
As the year progressed, CJS found more and more work being performed cost-effectively on its CNC router: a radius beaded faceframe that would have been manu-factured in several pieces was now made as a single unit in a fraction of the time; single piece wood HVAC and audio system ventilation grills; a single piece trellis with a 3D design that gives the illusion of depth. All are drawn in AutoCAD, then modeled and programmed in a matter of hours with Mastercam.
After CJS was using Mastercam for several months, an architect asked them to create a rectangular table with a very intricate deep cut pattern in a tabletop made from handpicked reclaimed white oak. The design, which was given to CJS as a photograph, called for cutting an extensive pattern of very deep pockets in 2” deep tabletop.
Scenna explained that hard reclaimed white oak could be very brittle so there is no room for error in making a piece of this sort. The hard oak pieces that comprised the tabletop panel were glued together with great care so that it would lay perfectly flat on the router table. The pattern was drawn in AutoCAD and imported into Mastercam. Ramping was used to make the pocket cuts less aggressive in order to avoid the poten-tial for chipping. Swept 2D and Ramping was used to create the movements for cutting all of the radius edges with a fluting bit. The radius cuts were completed in two passes.
Scenna estimated that creating this tabletop prior to implementing Mastercam would have taken several days. With the CAM software, it took several hours to pro-gram the CNC Router and about two hours to cut the tabletop.
CJS President, Christopher Sculti, said that the implementation of Mastercam has had a very favorable impact on his business including reduction of lead times, improved productivity for decorative millwork, and increased utilization of his large CNC router. In addition, the company is using advanced programming features of Mastercam to create pieces that require less sanding and other finishing operations after they are produced. These improvements, in many cases, have translated into more competitive pricing, which, in turn, has lead to the acquisition of additional business.