Setting Up Incoming Inspection for Your Machine Tooling

Incoming inspection practices for machine tooling vary greatly from company to company in how they process and inspect their incoming perishable tooling such as drills, taps, milling inserts, and other items purchased through a distributor. Usually, companies have not set up bare minimum checks that keep defects from occurring in their products due to tooling malfunction. Since tooling malfunction is an occurrence that could have a million different scenarios, companies are often not able to identify all and build checks and balances into their systems to avoid a costly defect from reaching the end user.

The simple checks they do put in place are often not enough, for example if a drill was to break in process during a drilling operation, companies (large major manufacturers) only have simple pins or a simple laser to detect if that operation was performed. To work towards "zero defects" a company needs to install some very simple inspection procedures prior to the machine tooling ever reaching the manufacturing floor.

Identify single point personnel to inspect your incoming perishable tooling, too often companies rely on various eyes to catch and eliminate tool malfunctions, and this is perfectly fine. But, in order to train personnel to catch defects in the design of the tooling or in how to approve tooling deviations in times of doubt, the company will have to invest in training specialists for this job. Specialists are often trained in the manufacturing practices of the company that actually makes the tooling, often even being trained by that company's representatives and technical staff. These specialists are often encouraged to attend training courses at the location for the manufacture of the machine tooling. This is a very good idea, because it is essential that a specialist understand the process that goes into taking raw materials and making it a machine tool. Large corporations don't need dozens of specialists, companies with about 700 to 1000 personnel really can do fine with a specialist on each of the shifts (providing the company is a 24 hour operation), someone who can be turned to in times of need. Small shops can usually get away with one person trained to do this, and often that one person has other duties as well.

These specialists are then to inspect the incoming tooling from the manufacturer prior to the release of this tooling to the production/manufacturing floor. This is done usually by taking one tool at random from a shipped in lot (example 24 drills arriving at same time from same batch) of tools and inspecting per that tool's blueprint specifications. The random selection is only performed because usually inspecting 100% all incoming is not feasible due to time constraints and cost. The manufacturer of the tool has to be responsible for something. All defects are the responsibility of the manufacturer and should be held accountable for any cost associated with the return or defect that tool caused. Set up a simple log for the specialist to fill out and allow it to periodically be inspected by plant management or supervision. The log needs to include date, time, person's name that did the inspection, pass or rejected, and steps taken if the item was rejected. If an item from a given lot is rejected then the entire lot must be inspected 100% to insure that the defect is not present. Again, the tool manufacturer should be responsible if the tooling does not meet a supplied manufacturer's approved blueprint drawing.

It is essential that a record of the inspection is present at all times for plant management or supervision to review. There are cases where sloppy record keeping usually means sloppy inspection, and if you are a Tier 1 supplier to a major automotive company such as General Motors, Toyoda or Ford, these records will be reviewed at some point and if you are a small shop making components on a tier 2 basis those records will come under scrutiny if a defect does occur downstream. If a record doesn't exist of the incoming inspection, which means it was not present when someone asked for the document, then it really never happened according to most customers and the responsibility of the defect downstream is now your fault and not the manufacturer of the machine tooling.

At all times the following should be in your designated inspection area. A file cabinet containing previous inspection reports, dated, and can be easily navigated by someone not familiar with the area (such as plant management or supervision who does not perform the task daily), and documents detailing how to properly perform an inspection on an item. The inspection tools such as calipers, mics, measurement machines, and all of these instruments need to have calibration or inspection stickers with dates present to insure that the instrument is actually checking incoming machine tooling correctly. There should be an area clearly identified that has machine tooling that is incoming but hasn't went through inspection yet, and there should be an area where machine tooling has been inspected and released to the production/manufacturing floor. The tooling specialist needs to be present, if he is not present, then there should be several ways to contact him posted in this area, and a back up person such as plant management or supervision to be contacted in case the specialist cannot be located. Also in that area should be the approved tooling blueprints that are readily available to inspect a machine tooling too. Too often companies forget this final act, and a customer comes in to investigate a concern and then asks the question, "what is he inspecting too", please do not say the specialist is going by memory only.

Setting up simple procedures, training appropriate personnel, and establishing an area that is designated to an incoming inspection process is the first step in reducing the occurrences of tooling defects and helping to reduce customer concerns and defects downstream.