The first place any machine shop that uses carbide end mills needs to look is at the proper handling and storage of all tooling. Carbide tooling is expensive, very expensive. They are also very fragile. During the manufacture of any cutting tool, be it an end mill, drill, or reamer, the material is handled as though they are eggshells, no two pieces ever come in contact with each other or anything.
One small chip will greatly reduce the life of the cutting tool. All new tooling comes in a nice individual plastic tube; even regrinds are dipped in a protective wax coating, to protect the delicate cutting edges. A lot of machine shops, (not all), treat their carbide tooling, in particular, after it has been decided it is ready for resharpening, like the chips it just cut.
On average a typical end mill can be resharpened (depending on wear) about 4 to 6 times. It is imperative that all the wear from any normal use be ground up sharp like new, plus any irregularities like chips and broken corners be removed.
Any unnecessary damage from handling or banging the cutting edges together means more material has to be removed to get the like new sharpness. This results in fewer regrinds, a short cutting length and shorter end mill life.
All end mills whether new or ready for resharpening should be kept in the original plastic case, or something suitable, versus thrown in a pile ready for regrinding.
I suggest that everyone in your shop who uses the tooling be made aware of what the tools costs, and be educated as to how to get the most out of your end mills. We have even recommended that machine shops purchase their own wax dip pot for about $100 and dip your worn tooling, before sending it out to be resharpened. It costs about 25%-30% of the original tool price to resharpen it, versus replacing it.
Extra special care should be taken when handling carbide reamers and high spiral end mills as they are more susceptible to damage than other tooling. Any irregularities have a tendency to show up magnified on the part being machined.
One last note, replace your cutting tool when it is worn, not when it fails!
Post time: 01-16-2017