From your perspective you will be looking for two types of manufacturers. In the first category are those companies which will make the individual parts you need for your product. The second group of manufacturers are those who will put your product together.
All manufacturers will vary in their levels of sophistication. This sophistication will typically be a function of their current or desired customer base. For example those manufacturers who supply to the automotive, medical or aerospace industries will be required to have very rigid quality systems, controlled manufacturing processes, order entry systems and so on. Such systems are, more often than not, dictated by the customer and are a condition of doing business. Adherence to these systems on the part of the manufacturer are often reinforced by on site audits carried out by the customer. So, these types of suppliers are at the high end of the scale and will usually price their services accordingly. These systems are not inexpensive to implement and the company must recoup its costs in some manner.
On the other end of the scale are manufacturers which don’t have all of the high end systems, but do a good job within their area of skill. These companies typically will have their own means of ensuring quality. They will also be the most cost effective and will tend to treat you on an equal footing with their other customers. It will be well worth your time to visit these folks and review these items:
- Ho w does the company take in and control your component specifications? You obviously want to ensure that each part made for you meets your requirements and that each part is identical to the next one. If a CNC program is written for your part, how do they ensure than no one messes with the program?
- Will they make and retain a “first off” sample part? They should use this part to make any initial verifications against your specifications.
- Do they have an equipment maintenance program? Do they have evidence that they follow that program? You do not want dull tools to be used to make your parts. If your part is a molded plastic part, how often do they tear the mold down and inspect for damage?
- How do they plan on storing your parts? Will they be in an area which is safe from damage and the environment? How do they handle your parts once done? Do they toss ‘em in a box thus exposing them to possible damage?
- How does the company handle your orders? How are they transmitted to the manufacturing operation?
- How will they ensure that the raw materials used in the operation are the ones that meet your requirements?
To dwell for a moment now on those companies which would assemble or put your product together, many of the same comments above apply. You will want to find a company which has good, demonstrable control over its assembly processes. The key here is that the processes must be consistent and repeatable. If they use a pneumatic screwdriver sometimes and a manual screwdriver at other times, this is bad news. If they use a manual screwdriver (thus having little control over tightening torque) and they should be using a pneumatic screwdriver which allows for consistent torque, then that is bad news also. How do they handle your parts between operations? If there is a problem with some of the parts that go into an assembly, how they assure that only good parts are used?
In general you can expect good results from suppliers for whom you have verified references, but your best insurance is that you personally review these key process items and make certain that your chosen supplier has all of these systems in writing and that they actually use them.