2018cnc4-5.2

36 www.CNC-West.com CNC WEST April/May 2018 and make it look nice. We are a fabricator. We know what our customers demand as far as tolerances go and we use 3D printing for actual parts, parts that are flying today.” Post processing is an avenue that many traditional 3D printing companies don’t offer, let alone have in-house. Roncelli Plas- tics will 3D print a near net shape then place the part on one of their 5- axis mills and finish it with features too difficult to do directly on the 3D printer. They clean it, install any inserts, and assemble it for shipping to the customer. “We can achieve what is needed through our complex secondary operations,” continues Chris. “You see the most degradation in the Z because the material is fused on that axis. If it meets the structural demands of the spec sheet, 3D printing is an efficient method to produce parts.” Roncelli Plastics has two big production Fortus 3D printers and another half dozen smaller units that they use for production as well as internal needs. “Internally we use our 3D printers often for fixturing,” describes Chris. “Fixtures on non-metallics have the same basic characteristics as you’ll find in any machine shop. Vic- es, jaws and so forth still hold the part, but we can print our own custom pieces to speed up the process.” They will print the fixture overnight then finish with a quick clean up before it’s ready to roll. “We don’t have to take time away from our production cells to machine fixtures. It is pretty handy.” Tight tolerance machining of non-metallics has a unique set of parameters different to that of standard materials used in the aerospace and medical industries. Non-metallics typi- cally are more susceptible to environmental changes than their metal counterparts. “The laminates we could machine in the parking lot,” jokes Chris and Riley. “Plastics generally speaking expand and contract at a rate of ten times that of most metals. Our tight tolerance parts regularly see us hold- ing 5 to 10 thousandths.” A slight change of 5 degrees in tem- perature can be the difference of them staying within spec or being out. Before having temperature controlled machining cells Roncelli Plastics would have employees come in early in the morning to run a part, then if need be finish the run later that night. “Here in So-Cal it can get hot in the shop,” details Riley. “Currently we have two of our three machining cells completely regulated at a steady and cool 68 degrees. The employees love it, and our customers appreciate our dedication to manufacturing precise parts. We started by climatizing our rapid prototype cell. The quick turn depart- ment was the smallest cell, and gave us a way to test out the benefits with the least amount of expenditure.” Right away they noticed less of a variance from part to part and how much easier it was for the operator to maintain the needed tolerances. The last of the three cells is scheduled to get their temperature controlled work environment later this year. Roncelli Plastics is a build to print contract manufacturer specializing in tight tolerance 5 axis machining of non-metallics, laminates and composites. The primary industries they server are aerospace, space, medical, and semi conductor. The regu- larly hold 5-10 thousands on the parts they manufacture.