In-House CMM: An Efficient Choice

Although shops should always be looking for ways to be economical, the economy’s current situation is a motivation to search for even more ways to cut costs and ensure efficient processes. One way to do so, if not in place already, is to bring CMM inspection capability in-house. More and more frequently, job shop aerospace and defense customers complying with AS9100 require discrete data to be recorded and stored. Shops that don’t have this capability yet can use an outside CMM service. However, while measuring services are completely capable, inspection fees and transportation costs add up, as does the wasted machine capacity if the part must be set up and reworked. Therefore, to manage a busy manufacturing process efficiently and cost effectively, most users agree that the CMM inspection process should be in-house.

MAPCO Precision Machining, a Canton, Mich.-based CNC parts manufacturing business, agrees that having its own CMM capability is an essential part of contract manufacturing today. However, this company had a disappointing initial experience with a CMM, according to George Merchant, president.

The company purchased a prominent brand from a reputable dealer and did everything right—they thought. But neither the manufacturer nor the dealer was able to resolve software difficulties. After trying to work things out, the project was eventually scrapped.

Mr. Merchant says, "As a result, we started looking around for a better solution and discovered Xspect Solutions Inc. through a search on the Internet. The Wenzel X-Orbit machine appeared to be exactly what we were looking for in terms of capability, work envelope, cost and availability."

MAPCO is a third-generation family owned precision machine shop that specializes in CNC milling and turning, screw machining, drilling, tapping and grinding of parts and components for the aerospace, defense, automotive and medical industries. Parts are manufactured in small or large quantities with a range of short- and long-term delivery schedules.

The shop was impressed with the robust construction of the Wenzel equipment and, in particular, its use of all-granite construction. Another benefit was that one of MAPCO’s three CMM technicians already was familiar with the OpenDMIS software that is provided with the CMMs. "He was very complimentary about the CAD capabilities of the software, which allows the CMM to be an integral part of the manufacturing process, permitting the generation of inspection programs before manufacturing is performed," Mr. Merchant explains. "Because we manufacture a range of aircraft and aerospace parts where CAD modeling capability is needed, we now have the ability to simply load CAD files and check them to the part." The data then can be stored and later retrieved at the customer’s request.

The shop purchased the Wenzel X-Orbit 8.10.7 CMM with a measuring range of 800 × 1,000 × 700 mm. It has a maximum 3D measuring speed of 700 mm/sec with maximum acceleration of 2,000 mm/sec², a 3-micron repeatability and a 5-micron volumetric accuracy. The OpenDMIS software is fully interchangeable with other DMIS-based CMMs. It is equipped with a Renishaw TP20 probing system.

MAPCO added the HT400RC wireless teach pendant to streamline CMM operation (or inspections) when working with larger parts.

"We were surprised to discover that the X-Orbits are manufactured in Wixom, Mich., which is very close to where we are located, so the logistics for providing training for our quality control people were very convenient," Mr. Merchant says. Wenzel/Xspect Solutions has built more than 70 CMMs in 2008 at the Wixom facility.

Mr. Merchant concludes, "We are very satisfied with the quality and performance of the CMM, and the software training process has provided a smooth integration into our manufacturing process. We’re confident that we now have the CMM inspection capability for our current and future needs. We’re also pleased with Wenzel’s customer support policy to provide timely software upgrades that can be conveniently and cost-effectively downloaded to the OpenDMIS software."

When a shop like MAPCO finds the right CMM to accommodate its needs, it makes the move to in-house equipment more economical.