Volume

CNC Lathe Manufacturing – Increasing Profitability in Low Volume Jobs

In this day and age of just in time manufacturing techniques utilized by many companies, CNC lathe manufactured components are being purchased just in time for assembly and just in quantities needed for assembly. This is being done to reduce inventory carrying costs. A major consequence of lowered purchase quantities is that the production behavior of CNC lathe manufacturing shops is reduced to low volume levels. The general complaint of many CNC lathe machine shop owners is that low volume manufacturing cuts into profits in a big way since the costs of operating CNC lathes is quite high, but customers are generally unwilling to pay higher component prices.

Now, one can either put on the complaining hat everyday and scream all day long and no one will ever listen; or one can use creativity and all of the engineering talents to convert these low volume CNC lathe manufacturing jobs into profitable ventures. In this article we will briefly outline the simple steps that can be taken to achieve this objective.

The first misconception is that high production rates are not warranted in low volume manufacturing. This cannot be farther from the truth. Machine utilization is what is critical in improving company profitability and hence production rates must be increased to as high a level as possible even in low volume jobs. Because it is easy to make money by scheduling three or four more jobs in the same CNC lathe one behind the other with minimal set up changes than to make profits by elaborate set up changes that reduce the number of jobs that can be performed in the same machine in the same given time period. The key to achieving this therefore, is to engineer jobs such that machine set up changes are kept to a minimum.

This requires foresight on the part of the programmer or manufacturing engineer that is tasked with these responsibilities.

The second factor that one needs to concentrate on to increase profitability in low volume CNC lathe manufacturing tasks is to spend some time up front and engineer to reduce the amount of material used in the component manufacture, which will reduce the associated material costs. Again, one will need to use creative engineering to accomplish this goal. Here are two ideas. First, use cut off inserts with as low an insert width as possible that will still provide the necessary sturdiness rigidity; as an example see if a three millimeter part cut off insert will be sufficient as opposed to a six millimeter part cut off insert. This will reduce the material usage for every piece that is cut. Secondly, adjust bar feeder proximity switches to allow for as low a chuck holding length as physically possible and still provide sufficient holding power; this will result in minimum remnants from material bar stock that cannot be used.

The third factor that will allow for increased profitability is to increase inserts and tool life. Once again, this will need a close look at machining feeds and speeds and proper coolant quality and flow. This will reduce costs associated with inserts as well as down time during insert changes.

Thus, one can use these three simple steps in order to increase profitability in low volume CNC lathe manufacturing orders, which as economic conditions seem to indicate, will be the purchasing trend for quite some time to come.