They say that ‘you can’t teach an old dog new tricks!’ NOT true! It CAN be done, but it’s not easy and this is where the expertise of CMM specialist Canadian Measurement-Metrology Inc. (CMMXYZ) comes in.
CMMXYZ recently took on a massive CMM remanufacturing and retrofit project. The ‘old dog’ in this case was a 33-year-old ‘monster’ DEA 4509 gantry CMM. It had been sitting in storage for the past 3 years at an aerospace manufacturing company in Western Canada. While large volume portable metrology equipment has eroded many of the traditional applications for these ‘monster’ CMMs, they can still have a role in manufacturing due to their accuracy and fully automated measurement capability. CMMXYZ had taken the machine as a trade-in and found it a new owner in the Tier 1 automotive sector.
Machines of this vintage were manufactured, similarly to very large machine-tools, using stress-relieved steel weldments with metal sprayed air-bearing guide-ways ground to precision on some of the longest grinding machines available at the time. Machines were manufactured intrinsically accurate without the sophisticated software error-maps found on today’s generation of CMM.
The CMM project was exceptional because of the CMM size. When fully assembled the machine stands 6 m tall, takes up 45 m2 of floor space and tips the scales at nearly 17,000 Kg. Regardless of size, most CMM rebuild and retrofit projects undertaken by CMMXYZ follow a basic template from start to finish. What begins as a mechanical project is then refined by integrating pneumatics and electronics and finalized with onsite calibration at the customer installation site.
The first phase of this project saw most of the heavy lifting to physically move the massive beams and columns into the CMMXYZ workshop. 4 days of CMM dismantling and shipment preparation, at the prior owners facility were performed. The machine was too tall for the CMMXYZ facility and therefor could not be mounted upon its pillars during the remanufacturing process.
With more than 30 years’ experience under his belt, the CMMXYZ machine builder was more than capable of taking on the massive project. In addition to overseeing each phase of the assembly, he had to make use of the in-house tool-room to re-machine and hone the Y-axis drive racks, clean and service all motors and gear boxes and completely re-align the Y-axis split beams.
Once the mechanical modifications were complete the focus was on the CMM pneumatics. On a CMM, pneumatics (air lines) play a crucial roll in the machine’s overall performance since the bridge assembly rides on air bearings. On this project, the CMM had to be completely stripped and the entire pneumatic systems re-engineered. The sheer size and weight added an extra challenge at this phase of the process.
The electronics upgrade is the ‘heart’ of any CMM retrofit. If the motors and gear boxes of these ‘monsters’ are the muscle of the CMM, then the controller is the brain. During the retrofit, the original controller was replaced with an adapted a Hexagon Manufacturing Intelligence RC1 controller interfacing with the Renishaw PH10M probing controller and PC-DMIS CAD++ software. The RC1 retrofit controller caters for medium and high-end bridge, gantry, and horizontal-arm CMMs supporting up to five configurable axes and providing up to 800W output power. To integrate the new controller and provide lasting reliability, the CMM XYZ electronics specialist upgraded all of the machine cabling to CMM motors, scale reader heads and the Renishaw probe head cabling.
PC-DMIS was installed running on a Windows 10 PC. It is interesting to note that the year the DEA Delta 4509 CMM was originally manufactured the Microsoft’s Windows Operating System was just one year old!
The final phase of this project involved CMM dis-assembly, crating, re-assembly and finally levelling and calibration onsite. The installation of the CMMs at its new home took 9 days for assembly, precision levelling and calibration. This style of CMM requires a foundation involving excavation to a depth of 5.5 m and needed below grade shoring due to the proximity of the building’s footings. Shoring involved the construction of a re-enforced retaining wall inside the excavation pit to prevent earth from shifting. This phase of the project took two months to complete.
The completed, retrofitted, CMM has a measuring volume of 2500mm x 6300mm x 1800mm, has been calibrated with a 0.023mm volumetric accuracy, and is ready to provide a further 30 years of measuring service.
Elliott Foster of CMMXYZ commented “We have transformed at least 10 of these old DEA ‘monster’ CMMs – they last forever.”
Who says monsters have become extinct? Canadian Measurement-Metrology are bringing these ‘monster’ CMMs from the past back to life again.
For more information: www.cmmxyz.com