Since its introduction, the “Edge Milling” function has become one of the distinctive features of Marmo Meccanica horizontal edge polishers. What is it exactly, and what are the benefits of this simple yet fundamental process? Both in the execution of a flat edge with flat beveled edges, and in more complex profiles, such as flat edge with pencil rounds or bullnose, there are two basic conditions in order to obtain quality results in one step:
- The edge must be perfectly square. This condition is necessary to have an upper and lower chamfers or pencil rounds of the same size or, in the case of bullnose, an upper and lower preparatory chamfer perfectly controlled in size.
- The processed piece must always remain in the “0 plane”, that is, always in contact with the working surface of the diamond heads. This is necessary for the same reasons as in the previous point. Furthermore, having a perfectly straight and well positioned edge during all transport through the machine guarantees not only a well-designed profile, but also a regularity along the entire length of the piece.
How to achieve all this without slowing down the production process?
The “Edge Milling” solution by Marmo Meccanica is simple: we have created a precision reference stop, whose function is to define the waste to be milled and squared by means of a dedicated diamond wheel, for a maximum of 6 mm.
In particular, the ingoing piece-gauging bar is adjusted by means of a reducer, which makes it move backwards with respect to the line of the vertical stop rollers with micrometric precision. The incoming piece is approached to the adjustable bar and, once transported up to the grinding wheel, it is square-milled and exactly in line with the vertical stop rollers.
The use of a diamond cup wheel for correcting laminations, various types of gluing and non-square edges surely guarantees more precise results than a disc or blade. In bullnosing machines, the milling head is an extra head dedicated exclusively to this function, while in straight-edge-polishing machines the first of the polishing heads (always equipped with a mechanical stop for diamond wheels) carries out the operation.
What are the advantages of Edge Milling?
- It ensures that the whole edge is, basically, regular and straight: instead of adjusting the functioning of the shaping and polishing heads to an irregular edge (laminated or out of square), the FC corrects the edge at the start, before processing.
- Not only does it guarantee a regular edge along the entire length, but, being a calibration in all respects, it allows you to have a controlled final piece width, thus correcting any cutting inaccuracies.
- If combined with an ingoing thickness calibrator, the Edge Milling calibrating action ensures a perfectly controllable edge in all variables (thickness, width, orthogonality). This means having the ideal starting conditions for all processes. In addition, the advantages become many with the addition of automatic positioning of the calibrator and chamfer: a true automation upgrade that simplifies and speeds up parameter management and production.
- It is the cheapest and easiest maintenance solution to the problems listed above, which impacts as little as possible on the performance/cost ratio of the machine and on maintenance costs, in line with all Marmo Meccanica technological solutions.
The working speed?
Of course it depends on the depth of the milling to be performed, but normally, up to a maximum of 3 mm, it does not alter the speed of execution of the rest of the work to be performed.