Quite often it is the simple ideas that enable great leaps in efficiency. This also applies to mold and die making. For the high standards required in machining today, the tools supplied by LMT Tools provide geometries and coatings which have already been optimized. That users can now quadruple their tool lives again, almost sounds Utopian. However, this leap has now been achieved by developers at LMT Tools - with the first precision-sintered, double-sided copy milling insert in the world.
Mold and die making requires high performance tools. They have to machine hardened steel and cast types at enormous cutting speeds and with maximum dimensional accuracy. With roughing and finishing of complex components, in particular, machining tools soon reach their limits.
One copy milling plate - two missions
Against this background LMT Kieninger - the Competence Center for mold and die making at LMT Tools - has been looking for options to increase the efficiency of the milling process even further. "We want to enable our customers to markedly increase productivity without having to make large investments", describes Hanjo Gissler, Product Manager for milling at LMT Kieninger. "To achieve this, we looked at one of the most important and most widely used consumables - the indexable insert."
The result is our new copy milling plate CopyMax2 for which we have a patent pending. It has improved cutting and material properties as well a fully functional second cutting edge - and all this in the proven LMT Kieninger quality. When the first cutting edge is worn, the insert can be turned over and re-used with the same tool life.
"Our challenge was to integrate the second cutting edge into the tool geometry so that the customer would be able to mount the milling insert accurately, securely and easily in the tool holder", explains Gissler. "The solution we developed includes a new conical shaft and a specially designed clamping screw as well as the copy milling plate. To attach the screw and to undo the indexable insert there is also a special Torx key available with a removable blade. The perfect interaction of these parts provides maximum process reliability."
High quality standard with HQS and Nanomold Gold
Another new feature is that the copy milling plate is manufactured using the High Quality Sintering (HQS) process. With this process, the tool manufacturer can achieve even more stable cutting edges thanks to the increased mold pressure and a special design. They are particularly beneficial for the work steps roughing and semi-finishing of large molds, as they enable machining of the material across large work piece surfaces with absolute process reliability. An additional feature is the special coating Nanomold Gold, developed by LMT Kieninger for the stringent requirements of mold and die making.
Quadruple tool life as a test result
During an internal test on a wave section made from cold work tool steel 1.2379, the ball nose copy cutter had already exceeded the expectations of the developers. The cutting speed was (vc) 240 m/min, cutting depth (ap) was 1.5 mm and the radial dept of the cut (ae) was 0.5 mm. In a direct comparison with an existing copy milling plate, the CopyMax2 plate already achieved more than double the tool life during the first chucking: around 470 min compared to 220 min with the same wear (100 µm max.). But there is also the second cutting edge which results in a tool life which is over four times higher - a clear leap in efficiency!
The new ball nose copy cutter will be available from LMT Tools from January 2016.