Case Study Brushed Finish
Our customer is a contract manufacturer of stamped metal parts. They had just won this job, which is an aluminum door for front-load clothes washers and dryers. The sheet was specified with a brushed finish. They were trying to brush the sheet with a hand rotated turntable under a fixed drill head using a woven abrasive and were dissatisfied with the variation of the result. The finish was not uniform from part to part and it was noticeable. This method also exceeded the seven second cycle time limit required to meet production demands. CDMC engineers developed a solution tailored to the customers needs.
The production volume was modest in scale, so an affordable and reliable system was required. The Model 9060 is a simple operator loaded machine that applies a perfectly consistent brush finish on every piece. After the operator loads a blank sheet and activates the cycle, the sheet is automatically pulled into the work area and positioned against locating pins. It is “clamped” from below with a vacuum table. A custom made brush assembly then lowers to contact the sheet for a specific amount of time. At completion the brush retracts and the sheet is automatically ejected from the machine to be collected by the operator.
Every variable that could affect the finished result was identified and controlled. The brush’s pressure, rotation direction, speed and contact time can be set specifically and repeatably. And each variable can be changed to accommodate different materials or other specifications, making the machine flexible in its application. The brush cores require so little pressure to brush the aluminum, they may never need to be changed (well, almost never). The start-to-finish cycle time met the seven second limit. This machine addresses our customer’s needs exactly, providing at modest cost a perfectly repeatable brushed finish in as little as seven seconds, while being flexible enough to accommodate future applications.