PVD coating of indexable inserts without hole has to face special challenges:
1. The cutting edges look into all directions and require a very spacious batching. Only a very homogenous film thickness distribution will lead to the top level of quality.
2. The selling prices for standard products have reached a very low level. Inside of the coating furnace the utilization must be optimized. Outside the furnace in cleaning, pretreatment and logistics the handling has to be minimized.
3. Insets without hole usually do not provide suitable faces to arrest the fixture. The customer expects all over coating as he is used from CVD, and does not accept spots or shadows due to the fixtures.
Spear fixtures solve these challenges. With respect to the economical aspects spear fixtures put the cutting edges open into the optimum position. The contact area to the product is minimized and leavs only a spot of the size of a needle tip. Beside of this the products may remain on the spear fixture of all steps of production and transportation.